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- Mesothelin Finding Could Lead to Early Detection of Mesothelioma
- New York Attorney Calls for International Ban on Mesothelioma-Causing Asbestos
- Protein Can be Reliable for Diagnosing Malignant Mesothelioma
- Biomarker Successes Remain Elusive For Mesothelioma and Cancer Researchers
- Avastin May Not be Effective for Breast Cancer, But is Still an Option for Mesothelioma
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- 3 Year Mesothelioma Survivor Stays Busy Raising Awareness of the Disease
- MesotheliomaHelp Website Offers Mesothelioma-Related FAQs
- CDMRP System Offers Funding Opportunity to Help Military Mesothelioma Sufferers
Friday, April 9, 2010
The American College of Chest Physicians’ website current Case Puzzler presents the case of a 70-year old woman with no history of occupational exposure to vapors, gases, dusts, fibers, or fumes, who is diagnosed with malignant epitheloid mesothelioma. Her physicians determined that she was a victim of “bystander asbestos exposure” from asbestos dust brought home on her father’s clothes throughout her childhood.
Mesothelioma is a rare, aggressive cancer that is primarily caused by exposure to airborne asbestos fibers. Symptoms of mesothelioma may not appear until up to 50 years after initial exposure to the asbestos. A wide array of workers were exposed to asbestos including shipyard workers, factory workers, pipefitters, sheet metal workers, plumbers, laborers, machinists, mechanics, powerhouse workers, and electricians.
Asbestos is so toxic that mesothelioma has been diagnosed in family members whose only exposure came from contact with the fibers that adhered to the clothes of the worker/tradesperson who actually worked with asbestos products. The woman’s father died of cancer of unknown primary site. The type of work in which he was engaged was not revealed.
The case study leads the reader through the steps of diagnosis including showing the results of the initial abdominal and chest CT scans indicating a left-sided pleural effusion. The next test, thoracentesis, was performed showing atypical cells suggestive of, but not diagnostic of, a malignancy.
The “answer” shows the complete diagnosis as well as a discussion including the patient’s medical history and information on mesothelioma diagnosis and treatment.
Case Puzzlers are brief clinical vignettes on various educational topics. Developed by members of the American College of Chest Physicians’ NetWorks, it provides members with an opportunity to sharpen their skills.
© MesotheliomaHelp.Net. All Rights Reserved. Reprinting or republication of this article or any portion of its content is permitted but must include the MesotheliomaHelp.Net link.
Labels: diagnosis, mesothelioma
posted by Nancy Meredith at 8:00 AM
Monday, January 11, 2010
Mesothelioma is a serious cancer that occurs in individuals exposed to airborne asbestos fibers. Even small amounts of asbestos and infrequent exposure can create a risk for contracting mesothelioma or other asbestos-related diseases. Most cases of mesothelioma are diagnosed 30 years or more after exposure. The latency period can be as long as 50 years.
The form of mesothelioma for which a patient is diagnosed is identified according to the body organ in which the tumor begins, known as its origin site. When mesothelioma affects the lining of the lungs it is known as pleural mesothelioma; when the lining of the abdomen is impacted it results in peritoneal mesothelioma. In rare instances, the lining of the heart can be affected resulting in pericardial mesothelioma.
Besides the location in which the tumors form, the other identifying factor in the diagnosis of mesothelioma is the histological subtype of the cancer. In terms of the histology of cells, there are three main types of mesothelioma:
Epithelial type. The epithelial type accounts for 50% to 70% of people diagnosed with mesothelioma. It is the most common and treatable histological subtype of mesotheliomas. Patients with this diagnosis have the best chance of recovery due to its slower growth and ability to respond to treatment.
Sarcoma type. The sarcoma type accounts for 7% to 20% of people diagnosed with mesothelioma and is the least common. Additionally, sarcoma mesothelioma has the worst prognosis, because it does not respond nearly as well to treatment as do the other two histological types.
Mixed or Biphasic type. The mixed type accounts for 20% to 35% of people diagnosed with mesothelioma. Biphasic describes a condition in which mesothelioma is comprised of both epitheloid and sarcomatoid cancer cells.
Each of the three cellular forms of mesothelioma are often treated in the same way. The medical team will determine the treatment of mesothelioma depending on the size and location of the tumor, whether the cancer has spread, and the patient’s overall health. For mesothelioma, the three primary types of treatment are surgery, radiation therapy, and chemotherapy.
Sources:
Cancer.net
MesotheliomaHelp.net
© MesotheliomaHelp.Net. All Rights Reserved. Reprinting or republication of this article or any portion of its content is permitted but must include the MesotheliomaHelp.Net link.
Labels: diagnosis, mesothelioma
posted by Nancy Meredith at 8:00 AM
Wednesday, May 6, 2009
Prior research has identified osteopontin (SPP1) as a potential tumor marker for malignant mesothelioma, as well as for other cancers, but little is understood about the biological activity responsible for this function. Molecular analysis of osteopontin has identified three specific isoforms of the protein, which are known as SPP1-A, SPP1-B and SPP1-C, but the relationship between these isoforms and carcinogenesis is also poorly understood. To learn more about these relationships, researchers from New York University’s School of Medicine conducted a study on tissue samples extracted from the resected tissue of patients with malignant mesothelioma and then compared their findings to a control group of healthy tissue. The researchers found that all of the isoforms of SPP1 were present in normal tissues, but that SPP1-A and SPP1-B were significantly up-regulated in the mesothelioma tissue, but SPP1-C was not. This was also the case when the researchers compared cases of primary mesothelioma to cases of recurrent mesothelioma, which led the researchers to conclude that SPP1-A and SPP1-B may be useful serum markers for mesothelioma diagnosis.
The researchers also looked at the tumorigenic activity of osteopontin and found that both SPP1-A and SPP1-B were associated with pro-tumorigenic activity, while SPP1-C was not. The researchers hypothesize that because the only structural difference between SPP1-A and SPP1-C is an exon that encodes an oligopeptide, future research may be able to develop a specific inhibitor to SPP1-A’s pro-tumorigenic activity. Such a development could be very beneficial to improving the efficacy of mesothelioma treatments.
This study was published in Biochemical and Biophysical Research Communications, under the title of “Tumorigenic properties of alternative osteopontin isoforms in mesothelioma.”
Labels: diagnosis, mesothelioma
posted by Joseph DiCastro at 2:26 PM
Monday, April 13, 2009
Researchers at Stanford University are developing a set of tests for diagnosing cancer that could lead to less invasive diagnostic methods, as well as more accurate results. Cancer is traditionally diagnosed with a tissue biopsy, where a doctor removes a selection of tissue and searches through the sample for evidence of cancerous cells. Biopsies are effective, but they are also invasive, potentially painful procedures and the results take time to process. The researchers at Stanford have developed a new test that can analyze a small drop of blood for the presence of specific proteins associated with cancer. The test is so accurate, that the research indicates it could also be used for much more effective tracking of patient progress and response to treatment.
The researchers were studying lymphomas, which are cancers of the lymph nodes, but they expect further research to show the same test would be effective for solid tumors, such as head-and-neck cancers. Much more research needs to be accomplished before this technology can be deployed on a regular basis, but it’s an excellent example of how our greater knowledge of cancer biology is leading to more effective diagnosis and treatments.
posted by Joseph DiCastro at 2:23 PM
Monday, January 5, 2009
Source: Rosetta Genomics
Rosetta Genomics has recently announced the availability of miRview(TM) meso, a new test for diagnosing mesothelioma that it developed using its proprietary microRNA-based technology. The new test provides precise differentiation between malignant mesothelioma and the various forms of lung cancer by identifying molecular differences between the two cancers. This is an important development for patients with mesothelioma, as the disease is often—mistakenly—described as form of lung cancer, even thought it’s actually quite different and requires different treatment strategies to maximize a patient’s therapeutic potential.
The availability of this new test gives mesothelioma specialists one more tool in their fight against pleural mesothelioma and peritoneal mesothelioma, as well as the disease’s rarest forms.
Labels: diagnosis, mesothelioma
posted by Joseph DiCastro at 5:13 PM
Friday, December 26, 2008
Source: Wired.com
Numerous studies have shown that the early detection of cancer is an important factor in maximizing a patient’s long-term prognosis. This is especially the case for aggressive cancers, such as malignant mesothelioma. Even though pleural mesothelioma—and the other forms of the disease, such as peritoneal mesothelioma and the its rarer forms—are not presently curable, the earlier identification of the malignancy usually means that more aggressive treatment can be performed and this has been shown to increase median survival time in most of these patients. The problem is that mesothelioma, like most cancers, is only diagnosed in its later stages, when it is more aggressive and has likely infiltrated larger tissue areas. This has caused some physicians and scientists to rethink the allocation of research monies from strictly curative approaches to ones focused on developing more effective tools for early diagnosis. One such foundation that is dedicated to this platform is the Canary Foundation, who was the subject of a recent article on Wired.com.
The Canary Foundation was started by an ex-executive at Cisco Systems, Don Listwin, who lost his mother to cancer after doctors failed to identify her cancer early enough. It is said that many forms of cancer are 90% curable when diagnosed at an early stage (this is, sadly, not the case with mesothelioma though), but because most research is only focused on curing late stage disease, Mr. Listwin felt it was ever more important to develop better screening structures to identify cancers at earlier times. To this end, he started Canary and positioned it a source of funding for oncologists and other research scientists who are pioneering new ideas for early detection.
Canary has not yet produced any breakthrough results, but the researchers they work with are pushing important boundaries. Whether their results will have demonstrable effects for patients with mesothelioma is unknown, but their work is a cause of hope for everyone whose lives have been touched by cancer.
To learn more about Canary, as well as more about early detection systems, we encourage readers to read the full article at Wired: Why Early Detection Is the Best Way to Beat Cancer.
posted by Joseph DiCastro at 4:50 PM
Friday, December 12, 2008
Radiological imaging techniques, such as CT (computed tomography) and MRI (magnetic resonance imaging), are some of the most important technologies used in the diagnosis of most forms of cancer, including malignant mesothelioma, because they allow the visualization of the underlying malignancy without the need for invasive biopsy techniques. However, mesothelioma’s unique morphological presentation can complicate these technologies’ ability to accurately determine the existence and extent of the disease’s infiltration of a person’s organs and tissue structures. Most forms of cancers present as individually identifiable tumors with clear borders and boundaries, so their presence within human tissue can often be identified by means of images alone. Mesothelioma’s typical presentation is quite different. Instead of a single tumor with clear boundaries, pleural mesothelioma and peritoneal mesothelioma are most often characterized by the diffuse spread of malignant tissue along the surfaces of large tissue areas, making a precise demarcation between malignant and non-malignant areas quite difficult. As is so often the case with this tragic disease, the accurate interpretation of these scans usually requires a specialist-in this case, a radiologist-with previous experience diagnosing the disease.
As indicated above, there are a number of different imaging technologies that can be deployed for a mesothelioma diagnosis. The different technologies have their own strengths and weaknesses and some are indicated for mainly diagnostic purposes and others are most commonly used to determine disease stage.
The most commonly used imaging technology in all of medicine is the x-ray, which is also the oldest of the technologies. The x-ray was developed for medical use in 1895, by the German physics professor Wilhelm Conrad Röntgen. X-rays have a number of important diagnostic functions, but they are rarely effective in the determination of mesothelioma. The principle reason for this ineffectiveness lies in x-ray’s poor visualization of soft tissue: the technology simply does not have the necessary resolution to accurately identify the manner in which mesothelioma invades tissue structures. An x-ray may indicate the presence of a pleural abnormality, but it will not be able to identify this abnormality as mesothelioma.
CT (computed tomography) is generally considered the “gold-standard” in the diagnosis of the disease, and is the most commonly prescribed imaging technology for this purpose, because of its ability to visualize the structure of the malignancy. Should an x-ray show some kind of abnormal shadowing, or should a physician suspect mesothelioma due to a patient’s symptoms and/or known exposures to asbestos, the patient will likely undergo a computed tomography scan of the suspected area. If the physician suspects pleural mesothelioma, this will likely be a chest CT; if the physician suspects peritoneal mesothelioma, this will be an abdominal scan. In many cases though, the physician may suspect an altogether different disorder and will be presented with a set of images indicative of mesothelioma.
CT, however, presents its own diagnostic limitations in the determination of mesothelioma. CT is often enough to visualize the presence of the disease, but the technology has known problems in soft tissue contrast, so the full extent of tissue infiltration can be difficult to determine. In these cases, MRI (magnetic resonance imaging) will be deployed, which features a much more accurate determination of tissue infiltration. For most diagnostic cases, CT will be fine, but MRI is especially useful when planning for surgery because it allows the surgeon more accurate images when planning his or her resection strategy.
Another common imaging technology used in mesothelioma treatment is positron emission tomography, known as PET, which is an altogether different technology than CT or MRI. Whereas those technologies are used for their ability to visualize local tissue structures, PET is most commonly used in the staging of the disease to determine if the disease has spread beyond local areas and metastasized to distant areas of the body. If PET determines the presence of distant tumors, the patient will be immediately upstaged and considered to have Stage IV disease, which means he or she will not be eligible for radical surgeries and aggressive treatment modalities. This is an important determination because the mesothelioma treatments that are most associated with enhanced survival are radical and invasive procedures and patients with late stage disease should be treated palliatively and spared the burdens of these aggressive techniques.
CT, MRI and PET are the most common imaging technologies used in the diagnosis and treatment of all forms of malignant mesothelioma. Much research is being conducted on combined modality PET/CT, which is a technology that precisely aligns the two imaging technologies and keeps their results synchronized, but it has not yet been made a standard technology in the diagnosis of the disease.
Labels: diagnosis, mesothelioma, peritonealmesothelioma, pleuralmesothelioma
posted by Joseph DiCastro at 10:41 PM
Wednesday, December 3, 2008
Source: American Journal of Clinical Pathology
Preoperative histologic assessment of mesothelioma tissue is one of the primary means by which mesothelioma specialists develop individualized treatment plans. It is commonly known that patients who present with epithelioid mesothelioma typically demonstrate better treatment response and longer survival times than do patients who present with sarcomatoid mesothelioma, so histological analysis is used to determine which patients will be treated with aggressive therapies and which patients will be treated more palliatively. However, a number of recent studies have noted that post-operative assessment of resected tissue is increasingly reclassifying the pre-op histological diagnosis so the value of determining mesothelioma treatment plans based on this preoperative prognosis is increasingly being called into question.
A group of researchers from the MD Anderson Cancer Center at the University of Texas have recently published the results of a small-scale study that looked at the value of preoperative histological assessment and its relationship to a final histological determination made after surgery. While their findings reinforced the notion that sarcomatoid mesothelioma is associated with a worse treatment response, they also showed a very high number of histological reclassifications and called for more study into this question.
Overview of the Study
The researches analyzed the results of 56 patients with confirmed pleural mesothelioma who underwent extrapleural pneumonectomy. The median age of this cohort was 61 years old. There were 50 males and 6 females. Preoperative staging identified 1 case of Stage I disease, 6 cases of Stage II disease, 33 cases of Stage III disease and 14 Stage IV cases. Preoperative histological analysis identified 37 cases of epithelioid mesothelioma, 9 sarcomatoid cases, 6 cases of biphasic mesothelioma and 4 cases where the type was not specified.
When the researchers compared the results of the preoperative histological diagnoses with those of the post-operative analyses they found significant differences between the two. Post-op analysis showed 21 cases of epithelioid mesothelioma, down from 37; 6 cases of sarcomatoid mesothelioma, down from 9; and the biggest change: 28 cases of biphasic mesothelioma, up from just 6 in the preoperative classification. These results showed that preoperative determinations of histological subtype cannot be used in a categorical manner to determine a treatment plan.
The researchers analyzed these results in a number of other ways as well. They showed that patients with sarcomatoid mesothelioma were associated with a 3.1x greater risk of dying from disease-specific symptoms than were patients with epithelioid mesothelioma. They also showed that patients who received some form of post-operative therapy, such as radiation therapy, demonstrated a greater than 70% decreased risk of disease-specific death or recurrence than patients who did not receive post-operative therapy.
Conclusion
Due to the high number of reclassifications, the authors conclude their article by questioning the prognostic value of preoperative histological analysis. They feel that the limited scope of the tissues made available during biopsy do not provide enough sample area to determine treatment strategies, especially because so little is known about the behavior of biphasic tumors. Because of this, they call for more research into the biphasic subtype of malignant pleural mesothelioma.
Labels: diagnosis, epp, mesothelioma, pleuralmesothelioma
posted by Joseph DiCastro at 5:39 PM
Friday, October 10, 2008
Source: Journal of Clinical Laboratory Analysis
Advances in our ability to diagnose mesothelioma in its earlier stages are among the most important developments in the recent fight against the disease. Along with the development of more effective treatment agents, these diagnostic advances have allowed physicians to begin treatment earlier than they have previously been able to—which is a key factor in their ability to extend patient survival and to improve issues related to a patient’s quality-of-life.
These advances in these diagnostic and treatment techniques have been the result of innovative research into the disease’s underlying biological activity. As scientists and physicians have learned more about mesothelioma, they have also been able to identify prognostic indicators that have enabled them to better identify the patient classes that will respond best to aggressive treatments and those whose disease requires a more palliative therapeutic protocol. This distinction is important because aggressive treatment protocols require highly invasive surgical techniques and a significant recovery time, so patients who present with specific disease characteristics that indicate poor treatability should not be burdened with such regimens.
The quest to identify more precise prognostic indicators for mesothelioma patients has taken many forms and the variety of research that is being conducted shows the interest that international researchers are now taking in studies of pleural mesothelioma and peritoneal mesothelioma. The latest example of this research is a paper that that has been published from researchers in Turkey. In an articled entitled “Pleural Fluid Findings as Prognostic Factors for Malignant Pleural Mesothelioma,” published in the Journal of Clinical Laboratory Analysis, they report the results of a retrospective study they conducted that analyzed the characteristics of pleural fluid in patients with pleural mesothleioma for any prognostic indicators it may contain regarding overall patient survival.
Overview of the Study
The researchers report that only one previous study had analyzed pleural fluid for its prognostic benefits, but only 26 patients had been enrolled in that study. In this study, they examined 71 patient records. There were 33 males and 38 females in the study population, with a mean age of 59 years. 23 people were smokers. Even though smoking has not been shown to have any causative affect on mesothelioma genesis, it is known to be a causative factor for a number of other cardiovascular diseases.
The patients were diagnosed by cytological or histological analysis, usually with a immunohistochemical panel that tested for combinations of calretinin, epithelial membrane antigen (EMA), thrombomodulin, HBME-1, CD15, B72.3 or carcinoembryonic antigen (CEA). Pleural fluid was analyzed for a number of specific characteristics, including pleural fluid glucose levels, lactate dehydrogenase (LDH), albumin, protein-to-serum levels and pleural fluid leukocyte counts. For their reported survival figures, the authors defined survival from date of thoracentesis to time of death.
Results
When the authors analyzed the results of the entire patient cohort, they found two independent prognostic factors that were indicative of survival: the ratio of pleural fluid to serum LDH > 1.0 and total leukocyte count in the fluid. They found a mean leukocyte count of 648+-860/mm3 for the entire cohort, but a significant increase in survival for those patients with a count of >700/mm3. When patients who used diuretics were excluded from these results, they found that fluid glucose levels also achieved statistical significance as a predictor of survival.
Conclusion
This study has indicated another set of prognostic tests that physicians can use in their determination of survival and overall prognosis for patients with pleural mesothelioma. These results will need to be independently verified before their scientific and medical value can be fully validated, but this study provides valuable information about specific biological factors involved with mesothelioma. The authors also note that the low leukocyte mean suggests a “weak inflammatory reaction against the tumor” and they suggest the “stimulation of antitumor response” is a possible treatment avenue for mesothelioma patients.
Labels: diagnosis, mesothelioma, pleuralmesothelioma
posted by Belluck & Fox at 2:51 PM
Tuesday, September 23, 2008
Source: Current Treatment Options in Oncology
Advances in diagnostic technologies and treatment-related procedures for mesothelioma patients have led to enhanced survival times for a number of different patient classes. These advances have allowed physicians to diagnose the disease sooner than they’ve previously been able to diagnose it, which allows treatments for mesothelioma to begin at an earlier time as well. However, not all patients are eligible for these new procedures and most still receive a diagnosis in the disease’s later stages when radical surgery is not an option. Because of this, research into pleural mesothelioma and peritoneal mesothelioma continues on a number of important fronts.
A series of articles on mesothelioma have recently been published in Current Treatment Options in Oncology, an important medical journal that features expert commentary on contemporary treatment practices for a number of different cancers. One of these recent articles is a report on the diagnosis, staging and surgical treatment of pleural mesothelioma. The article describes the current thinking on these topics and provides a detailed overview of the current mesothelioma staging system.
Overview of the Article
The article is divided into three basic sections: Diagnosis, Staging and Surgical Management. The section on mesothelioma diagnosis describes the “clinical and radiological presentation” of the disease, as well as some of the steps and procedures involved with pathology analysis. The section on staging describes, in detail, the current staging system used for pleural mesothelioma patients. The final section describes various treatment protocols featuring surgical intervention.
Mesothelioma Diagnosis
When the disease is in its earliest stages, the results of physical examinations are “non-specific,” but they quickly become more serious as the disease progresses. CT (computed tomography) scans are the preferred imaging modality for most cases of mesothelioma. MRI features enhanced resolution and soft-tissue contrast over CT, but for basic diagnostic purposes the images provided by CT are more than adequate. CT’s principal failing is poor presentation of chest wall involvement and tumor infiltration of certain pleural structures, so MRI may be indicated for these particular purposes, but CT is adequate for most cases of preoperative staging.
The article also discusses a study conducted by Dr. Harvey I. Pass that showed how three-dimensional CT imaging can be used to conduct pre-operative tumor volume analysis. Dr. Pass found that CT was able to measure tumor bulk and to predict survival times among patients with different levels of tumor volume, so CT is said to have both diagnostic value and prognostic value.
Another common imaging system in mesothelioma diagnosis is PET (positron emission tomography). PET is an important diagnostic modality because it specializes in the identification of distant metastases, something that CT is simply unable to do. Because radical surgery requires patients to be in the best overall health, any evidence of distant tumor seeding is a negative indicator for this kind of procedure. Even as staging is PET’s primary function in mesothelioma treatments, there is evidence that indicates PET can also be used to predict median survival in some patients.
Imaging technologies are the standard non-invasive diagnostic procedures, but a definitive diagnosis requires pathology assessment. The most common procedures that physicians deploy for sample extraction and analysis are thoracentesis, thoracoscopy and VATS. Due to its highly invasive nature, thoracotomy is not indicated for exploratory surgery.
When the sample has been removed, a pathologist must examine the specimen for malignant indications. Immunohistochemistry analysis is the standard testing methodology to determine a diagnosis. Because no single marker is 100% positive for mesothelioma, most of these analyses test against a panel of antibodies and use a combination of positive stainings and negative findings to determine a complete diagnosis.
For more information, please read mesothelioma diagnosis.
Mesothelioma Staging
A variety of staging systems have been proposed for mesothelioma, but all of them have had some notable downsides. The current system in use was developed by the International Mesothelioma Staging Systems group and is a 4-stage system that is based on a TNM model that represents an individual’s present state of tumor spread (T), lymph node status (N) and existence of metastases (M). Within each of these designations, there are individual status designations and the final staging decision is based on combining the statuses of each of the constituent models. The T value measures the extent of tumor bulk and spread, and has 5 possible values: T1a, T1b, T2, T3, T4, with T1a the best case scenario for mesothelioma patients, meaning limited tumor bulk, with no involvement of the visceral pleura. The N status has 4 possible values: N0-N3, again with N0 the best case, meaning no lymph node involvement. The M status is a value of 0 or 1, meaning no distant metastases or any evidence of distant metastases.
These designations are then put together to determine an individual patient’s current stage. The staging system is as follows:
| Stage | T Status | N Status | M Status |
| Stage I – Ia | T1a | N0 | M0 |
| Stage I – Ib | T1b | N0 | M0 |
| Stage II | T2 | N0 | M0 |
| Stage II | Any T3 | Any N1 and N2 | M0 |
| Stage IV | Any T4 | Any N3 | Any M1 |
For more information, please read: mesothelioma stages.
Surgical Management of Mesothelioma
Most patients who are diagnosed with mesothelioma receive a diagnosis later in life. Because of this, accurate staging of patients is an important element in developing a treatment plan, especially a plan that can include surgery. Older patients are less likely to tolerate the invasive surgery and extensive recovery associated with mesothelioma surgeries. Patients with no evidence of metastases and limited tumor involvement are the target patients for surgical intervention and multimodal therapy. Those with M1 status are immediately not considered for radical surgery. For patients who are between the best and worse cases though, a judgment call must me made by their physicians as to appropriate an treatment course.
Multimodal protocols featuring surgery, chemotherapy and localized radiotherapy remain the best way to extend median survival for eligible patients, but there is still much research being conducted on which combination of modes is the most effective in treating mesothelioma, so definitive statements on treatment methods are not yet possible. The role of pleurectomy/decortication vs. extrapleural pneumonectomy is one of the most controversial questions among mesothelioma physicians. A number of studies have been done, but the choice often comes down to the choice of individual surgeons. There are a number of other controversial questions as well, such as the the question of whether chemotherapy should be deployed in an adjuvant or a neoadjuvant manner for greatest treatment efficacy.
For more information on mesothelioma treatments, please read: Mesothelioma Treatments: Surgery and Mesothelioma Treatments: Chemotherapy and Radiation.
Conclusion
Even as research as improved the efficacy of our treatments, mesothelioma still remains one of the most difficult of all cancers to treat effectively. The work that is currently being conducted by physicians and researchers is an important step in changing the dynamics of mesothelioma treatment and diagnosis.
Labels: diagnosis, mesothelioma, staging, surgery, treatments
posted by Belluck & Fox at 4:03 PM
Monday, August 25, 2008
Source: Annals of Thoracic Surgery
Lymph node status is an important indication of disease spread and treatment prognosis for patients with pleural mesothelioma and peritoneal mesothelioma, just as it is for patients with other forms of cancer. Patients who present with lymph nodes that are negative for cancerous invasion are considered early stage patients and they typically respond to treatment in a more robust manner than do patients with “positive nodal status,” that is, patients whose disease has metastasized to their lymph nodes. Mesothelioma staging sees any indication of positive nodal status as increasing the staging diagnosis, but little is presently understood about the meaning of the nodal groups that do exhibit infiltration. The mediastinal lymph nodes are the nodes most likely to experience metastasis, but the hilar lymph nodes are also a common location of cancerous invasion and the question remains open if positive nodal status of both the mediastinal and the hilar nodes is indicative of a more advanced stage of the disease than is mediastinal metastases alone.
To answer this question, researchers from Egypt conducted a study in which they investigated the “prevalence and pattern” of lymph node metastases in a selected group of patients. Their research has recently been published in the Annals of Thoracic Surgery.
Overview of the Study
The researchers conducted a retrospective study of 53 patients with biopsy-proven malignant pleural mesothelioma. During treatment, each patient received a contract-enhanced CT scan of the chest and upper abdomen, as well as chest roentgenogram and ultrasound of the abdomen and pelvis. All patients underwent spirometry, while some patients received MRI and others underwent bone or brain CT if clinical analysis suggested it.
The study group was divided into two cohorts for analytical purposes. The first cohort, made up of 37 patients, did not receive pre-operative mediastinoscopy and each patient underwent a multimodality treatment protocol. The second cohort, made up of the remaining 16 patients, received preoperative staging assessments via mediastinoscopy. In this cohort, patients whose lymph nodes were negative for metastases underwent trimodal therapy using surgery, radiation and chemotherapy, while patients who demonstrated positive nodal status were excluded from the trimodal therapy.
All of the patients eligible for extrapleural pneumonectomy underwent EPP and during surgery, the physicians conducted lymph node dissection and sampling which revealed a patient’s true disease stage.
Results
There were 33 men in the study and 20 women. 34 patients presented with epithelial mesothelioma, while 16 presented with biphasic mesothelioma and 3 with sarcomatoid mesothelioma. Among the patients who did not receive preoperative staging assessments, 12 patients were subsequently identified as having mediastinal or hilar lymph node involvement. 11 patients were identified as having mediastinal metastases and 5 were identified with hilar metastases. However, of the latter group, four patients had both hilar and mediastinal involvement, while one patient was positive for hilar node involvement without concurrent mediastinal involvement, so the group figure for nodal involvement was set at 12. In the second group, 6 patients demonstrated nodal metastases. Mediastinoscopy revealed the nodal involvement in four of these cases, while two were discovered after surgery. All in all, 18 (34%) cases of lymph node metastases were uncovered in this study.
When analyzing the relationship between histological subtype, overall aggression and nodal infiltration, the researchers confirmed that the sarcomatoid and biphasic subtypes of the disease were more aggressive than the epitheloid subtype. They found that all patients whose disease had infiltrated their lungs presented with either sarcomatoid or biphasic mesothelioma. The researchers also found that this group of patients was more likely to demonstrate lymph node metastases than were patients with epitheloid mesothelioma. Of the 18 total cases with nodal metastases, 42% (8 cases) had sarcomatoid or mixed mesothelioma, while only 29.4% (10 cases) had epitheloid mesothelioma.
While nodal metastases are always indicative of a more advanced stage of the cancer, the authors conclude that differences in the nodes that were invaded must also be considered when staging. They state that the mediastinal lymph nodes should be considered the primary mesothelioma nodal station and indications of positive mediastinal lymph node status should be staged as N1 disease, while hilar metastases represent a more advanced cancer and should be recognized as N2 disease.
The authors also state that while mediastinoscopy is not a prefect diagnostic tool, it can be important for the preoperative staging of mesothelioma patients because it can reveal the presence of nodal metastases that PET or CT cannot. EBUS-TBNA represents the latest diagnostic advancement for the staging of pleural mesothelioma, but is not yet widely used, so until it becomes more commonly utilized, the authors state that PET, CT and mediastinoscopy should be the basic staging tools deployed in the diagnosis of mesothelioma.
Conclusion
The authors conclude their article with a call for revisions to the mesothelioma staging guidelines, as well as for more research into this topic. A number of previous studies have shown that early diagnosis of mesothelioma is an important indication for disease treatability, so improvements in the accurate diagnosis and staging of the disease will be helpful to many people whose lives have been touched by this difficult disease.
Labels: diagnosis, mesothelioma
posted by Belluck & Fox at 5:02 PM
Monday, August 11, 2008
Source: Mutation Research
That exposure to asbestos is the cause of all forms of mesothelioma has been definitively known for many years. Evidence for this relationship was uncovered as early as the 1920s, but the asbestos companies hid this information for as long as they could, so it wasn’t until the 1960s that the carcinogenic aspects of asbestos became true public knowledge. In the wake of the incontrovertible evidence of the mineral’s disastrous health effects, the United States—and nearly all other developed nations—enacted stringent regulations regarding the use of asbestos or outright bans on it. However, these regulations came too little and too late for workers with previous exposures to the fibers. To this day, the United States sees approximately 2500 yearly deaths from mesothelioma and international health organizations estimate that, worldwide, asbestos-related diseases claim 15,000–20,000 lives each year.
Pleural mesothelioma is the most common form of mesothelioma and is commonly associated with a poor prognosis. Mesothelioma treatments are not effective for the long-term management of the disease and most people who are diagnosed will die within 16 months. One of the major reasons for this poor prognosis is that the disease is often misdiagnosed or not diagnosed at all until it hits the later stages, when pleural tissue structures feature significant infiltration and tumor spread that make effective treatment impossible. Studies have shown that earlier diagnoses often correlate with better prognosis and treatability, so there is a great attempt to develop tests that can return a mesothelioma diagnosis earlier than current methodologies allow.
One such research project is actively investigating what, if any, biomarkers are indicative of mesothelioma. A biomarker is a biochemically-expressed substance, such as a protein, that can be used to identify a cancer before its regular symptoms assert themselves. The hope among mesothelioma specialists is that the development of effective biomarker tests will lead to much earlier diagnoses of the disease. Researchers from Italy have recently released the results of a study they commissioned on the use of biomarkers in the diagnosis of mesothelioma and lung cancer. Their data suggests that a combination of elements can be used together to identify the malignancy in high-risk populations.
Overview of the Study
Previous research into the biochemical and genetic foundations of mesothelioma has revealed that a number of specific proteins, growth factors and other substances are significantly over-expressed in mesothelioma patients. These studies have indicated that some of these substances, either singularly or in combination, could be effective for the early diagnosis of asbestos-related diseases (ARDs). The identified substances include 8-hydroxy-2 -deoxyguanosine (8OHdG), interleukine-6 (IL-6), platelet-derived growth factor (PDGF-BB), hepatocyte growth factor (HGF), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF) and soluble mesothelin-related peptides (SMRPs).
To investigate the efficacy of these substances for marker purposes, the authors enrolled 119 subjects with a history of asbestos exposure into their study. This group was analyzed according to occupational exposures to the fibers, including total exposure burden and duration of exposure. This information was used to develop a risk factor analysis for asbestos-disease and mesothelioma development. They also enrolled a control sample of 54 age-matched individuals who did not have a history of asbestos exposure.
The asbestos workers underwent clinical examination, chest radiography and high-resolution CT, while the control group received chest x-rays that all returned normal results. Both groups had blood drawn that was analyzed for the presence of the identified markers using the standard tests for each substance.
Results
The authors analyzed the presence and distribution of the various markers by sex, smoking history, age, gender and asbestos-group vs. control-group membership. Within the asbestos group they created a job risk assessment that showed that some occupations, such as hands-on work related to pipe fitting, maintenance work and other shipbuilding functions, carried the highest levels of exposures, while office work in environments surrounding areas that featured direct exposures was associated with a significantly less fiber burden.
They found that risk of malignant mesothelioma increased according to cumulative asbestos exposure. 80HdG and IL-6 levels correlated with high levels of SMRPs, which were associated with workers demonstrating the highest asbestos burden. They also found that these groups were most likely to have other asbestos-related diseases (ARDs), such as pleural plaques and fibrosis. The maintenance worker subgroup presented with a 71% of ARDs, pipe fitters with a 57% ARD rate and 50% of electricians were found with ARDs. This is a strong indication of the risks associated with direct exposure, especially when compared to the office worker subgroup which only demonstrated a 10% ARD rate.
Workers demonstrating the highest risk for mesothelioma due to occupational exposure to asbestos also demonstrated higher levels of angiogenic growth factors, such as platelet-derived growth factor (PDGF-BB), hepatocyte growth factor (HGF), basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF). Angiogenesis is the process by which new blood vessels are formed within tissue structures and it is directed through growth factor signaling pathways. While angiogenesis and growth factor expression are necessary processes for many aspects of tissue growth and are not directly representative of malignant developments, they are absolutely essential for tumor growth, as tumors need blood to fuel their growth and spread.
The authors indicate that prevoiusly-identified “preclinical and clinical evidence suggests that angiogenesis may be a critical step in the pathogenesis of mesothelioma.” Several studies have previously reported on the high levels of VEGF, bFGF, HGF and PDGF found in mesothelioma cells. There is even evidence to suggest that these growth factors form autocrine growth loops in mesothelioma, which means that aside from their facilitation of blood vessel development to mesothelioma tumors, these growth factors may also stimulate the proliferation of mesothelioma cells themselves.
Conclusion
The authors conclude that combination analytics using both growth factor levels and SMRP levels in high-risk populations could be used for mesothelioma diagnoses. Growth factor expression can be indicative of underlying tumor genesis, but these proteins are not specific to mesothelioma, while SMRP levels can be used to separate healthy individuals from mesothelioma patients, but haven’t had the same success in screening out potential mesothelioma patients from other high-risk, asbestos-exposed populations. Thus, screening methodologies that take both elements into account could possibly function as an early diagnostic marker for pleural mesothelioma.
Labels: diagnosis, mesothelioma
posted by Belluck & Fox at 4:24 PM
Thursday, August 7, 2008
Source: Journal of Ultrasound in Medicine
There are four basic forms of malignant mesothelioma: pleural mesothelioma, peritoneal mesothelioma, pericardial mesothelioma and mesothelioma of the tunica vaginalis. Pleural mesothelioma is the most common form of the disease, followed by peritoneal mesothelioma. The other two forms are actually quite rare. Pericardial mesothelioma is only diagnosed in a small percentage of cases, while diagnoses of mesothelioma of the tunica vaginalis are exceptionally rare.
The available literature on reproductive mesothelioma, as it’s sometimes called, is made up of less than 100 individual cases, so little is known about its etiology and overall behavior. New case reports are generally the only way in which physicians can share their experiences with this disease, so the findings are widely reported on when they do appear. A recent issue of the Journal of Ultrasound in Medicine has published the latest report on this rare malignancy. The article describes the authors’ experience treating a 60 year-old man diagnosed with mesothelioma of the tunica vaginalis, as well as their use of a new imaging technology in the preoperative diagnosis of the disease.
Overview of Mesothelioma of the Tunica Vaginalis
Mesothelioma of the tunica vaginalis is the rarest form of malignant mesothelioma. The authors of this article state their awareness of only 98 other cases. Different articles have reported slightly different numbers, but the basic truth of these statements refers to the extreme rarity of the disease. Asbestos exposure is the most commonly reported causative factor, but specific conclusions are very difficult with such a small population set to learn from. Histologically speaking, most cases of the disease are of the epitheloid subtype (60-75%), with the biphasic subtype making up the remainder of diagnoses. The authors state that “pure sarcomatous mesothelioma is exceedingly rare.” The average age of diagnosis is 60 years-old and because the disease specifically grows from the tunica vaginalis—the lining that surrounds the testes—it only affects men.
In most cases, the disease remains undiagnosed until the area is operated on or an autopsy reveals the presence of the malignancy after a patient has died. If a patient does present with a testicular issue, the disease is likely to be misdiagnosed for a number of more common conditions. This situation—as is the case with most forms of mesothelioma—means that the malignancy is likely to be in a less treatable state when a diagnosis is finally returned.
Overview of the Case
The authors describe the patient as a 60 year-old man with swelling on the left side of his scrotum. The man smoked for twenty years, but was not occupationally exposed to asbestos. Like all forms of mesothelioma, asbestos exposure is the main indication for this varient, so it is likely that the patient was simply not aware of his exposure to the mineral. Many diagnostic tests returned normal results, but sonographic testing revealed a number of troubling findings, including an enlarged left testicle and a large hydrocele in the left scrotum. A 1.5 x 1 x1.5-cm polypoid mass (polyp) demonstrating “increased vascularity” was discovered in the scrotal wall, and two similar masses were discovered in the tunica vaginalis.
The patient then received a left hydrocelectomy and scrotal exploration and had tissue removed for biopsy. The biopsy revealed mesothelioma of the tunica vaginalis, biphasic subtype. After a left radical orchitectomy and hemiscrotectomy, a 4-cm tumor attached to the tunica vaginalis was discovered. Immunohistochemical analysis conducted on the tumor confirmed the mesothelioma diagnosis.
Further testing revealed that the cancer had metastasized to the retroperitoneal lymph nodes. The patient then began chemotherapy. 21 months after initial diagnosis, PET indicated distant tissue infiltration and CT demonstrated significant metastases in the lungs and mediastinum. After this discovery, the patient was started on another course of chemotherapy.
Color Doppler Sonography
As we stated above, most cases of mesothelioma of the tunica vaginalis are not diagnosed until surgery or autopsy. Due to its rarity, most physicians will not have any experience with the disease and will certainly not be on the lookout for it. Regarding the case under discussion, the authors were able to identify the disease fairly early and were able to start treatment for it soon after discovery—which was almost certainly a factor in the patient’s survival 21 months after initial diagnosis. The authors state that imaging methodologies have traditionally been of limited use, but research into the sonographic representation of the tumor has begun to identify characteristics particular to it. Along with that research, the use of newer technologies in the analysis of tissue structures has also been important. For this particular case presentation, the authors used color Doppler sonography to identify areas of increased blood flow (hypervascularity) in the identified scrotal masses, which indicated the presence of a possible malignancy. Color Doppler sonogrography is an ultrasonic imaging technology that identifies blood flow and represents these varying rates using colors. Many scrotal masses are relatively benign conditions and do not demonstrate increased vascularity, so the use of an imaging technology that is sensitive to increased blood flow can help to differentiate the mesothelioma from other conditions. If a malignancy is suspected, fine needle aspiration or the removal of tissue—in addition or, or instead of, the excision of the affected testicle—can be attempted to definitively determine a diagnosis.
Conclusion
The authors conclude that color Doppler sonography may be an important new tool for the diagnosis of mesothelioma of the tunica vaginalis. Mesothelioma is a very aggressive tumor in all its forms, so early diagnosis and treatment is a key element in maximizing patient survival time. Because the disease is so rare, it is unlikely that studies will be attempted to precisely quantify this technology’s diagnostic value, so case reports such as these remain the best way to learn more about mesothelioma of the tunica vaginalis.
Labels: diagnosis, mesothelioma
posted by Belluck & Fox at 4:04 PM
Tuesday, August 5, 2008
Source: Histopathology
An early diagnosis of mesothelioma is one of the most important aspects of maximizing a patient’s prognosis. A number of studies have correlated early diagnosis with enhanced survival time, so the identification of the most efficient diagnostic technologies is an important aspect of contemporary mesothelioma research.
Physicians have developed a number of biopsy procedures for cancer diagnosis and some of these procedures are used to diagnosis pleural mesothelioma or peritoneal mesothelioma. There are two basic biopsy strategies for most forms of cancer diagnosis: closed biopsy and open biopsy. A closed biopsy refers to the removal of tissue samples from outside the body, using small incisions and the insertion of specific surgical tools for the removal of tissue. A “blind” biopsy refers to a closed biopsy where the physician has no visual indication where his or her instruments are actually taking tissue samples from. Image-guided biopsy refers to the use of CT, or another imaging modality, to guide the physician’s needle during a closed biopsy. An open biopsy traditionally refers to a biopsy completed during invasive surgery, where the physician has a wide view of the affected areas.
When a biopsy is taken for pleural mesothelioma, it is called a pleural biopsy and the same basic strategies apply: closed pleural biopsy refers to a biopsy where tissue samples are removed from the pleural cavity, while open pleural biopsy refers to a biopsy completed during a thoracotomy, a highly invasive surgical procedure that provides wide access to the pleural cavity through a large incision made on the patient’s side and the spreading of the patient’s ribs to facilitate access to the thorax. In contemporary times, an open pleural biopsy may refer to a biopsy conducted through video-assisted thorascopic surgery (VATS), which is a much less invasive procedure than is a thoracotomy.
From these descriptions here, it is easy to assume that open pleural biopsy would give a physician the greatest diagnostic accuracy, while a blind, closed pleural biopsy would provide the least. Even though this is true, the invasiveness of the thoracotomy is generally avoided where possible, so mesothelioma specialists have had to settle for other less accurate techniques when the symptoms displayed during patient presentation are not necessarily indicative of a more serious illness. Image-guided pleural biopsy and VATS have very much increased the accuracy of the less invasive techniques, but they are not yet universally deployed.
Researches from the United Kingdom have recently entered this discussion with their publication of an article that analyzed the accuracy of the aforementioned biopsy techniques.
Overview of the Study
The researchers analyzed the postmortem records of 45 patients who died from pleural mesothelioma at Llandough Hospital in Penarth, Wales in the UK. These records identified the various diagnostic tests completed for each patient, from biopsy procedure to immunohistochemical analysis, and they served as the researcher’s primary data set for their analysis. Among these 45 cases, there were 21 cases of epithelioid mesothelioma, 11 cases of biphasic mesothelioma and 13 cases of sarcomatoid mesothelioma. 41 of the 45 cases were diagnosed when the patient was still alive, while 4 were suspected of mesothelioma, but a diagnosis was never returned.
Of the diagnosed cases, 36 underwent a closed needle biopsy. 31 of these were “blind” biopsies and 5 were CT-guided. Within the same population of diagnosed cases, 21 patients underwent an open pleural biopsy through thoracotomy.
Results
The researchers found results similar to other researchers who have also looked at this question: open pleural biopsy was the most accurate and sensitive procedure, while a blind, closed biopsy was the least accurate. Of the 21 cases of open biopsy performed through thoracotomy, all 21 cases were correctly identified as pleural mesothelioma and the histological subtype was correctly identified in 20 of the 21 cases. The blind biopsies were considerably less accurate and often required multiple procedures to return a diagnosis. When the procedures were quantified, the authors reported a diagnostic accuracy of only 16% of the 31 cases.
However, the accuracy of CT-guided closed biopsy was again confirmed. All five of the CT-guided cases returned an accurate diagnosis on the first attempt at biopsy, for a diagnostic accuracy of 100%—a figure that is directly comparable to thoractomy. Five is a rather small number though, and the other studies that have looked at image-guided biopsy have returned accuracy results in the high 80s or low 90s. That said, CT-guided biopsy is clearly a highly accurate diagnostic method.
Conclusion
This article is the latest among a number of recent publications that confirms the poor diagnostic accuracy of blind biopsy techniques. While open biopsy remains the surest way to determine a diagnosis, the use of CT-guided, or other image-based, closed biopsy has also shown a remarkable accuracy in the diagnosis of mesothelioma. These techniques are much less invasive and can be conducted under less extreme situations. Along with immunohistochemical analysis, as well as other pathology and marker tests, these diagnostic advances have enabled physicians to diagnose the disease much earlier than they ever have been able to. Because of this, patients can begin treatment at an earlier point in time, which may extend their survival time. Even as mesothelioma remains without a cure, recent improvements in diagnostics and patient survival are cause for some hope.
Labels: diagnosis, mesothelioma
posted by Belluck & Fox at 4:08 PM
Thursday, July 17, 2008
Source: Current Opinion in Pulmonary Medicine
Efficient diagnostic techniques are important in the diagnosis of all forms of cancer, but this is especially true for people who are presenting with symptoms that are indicative of mesothelioma. The disease ranks among the most aggressive malignancies and remains very difficult to treat effectively, especially when a diagnosis is received only in its later stages. A number of studies that have investigated prognostic factors in relation to effective treatments have concluded that an early diagnosis of pleural mesothelioma or peritoneal mesothelioma is among the most important variables in maximizing treatment potential. Thus, efforts to improve a physician’s ability to accurately diagnose the disease are among the most common research projects that are currently underway.
In an effort to add to the available literature on the subject, physicians from the United Kingdom conducted a study to determine the efficacy of using image-guided pleural biopsy techniques in the diagnosis of mesothelioma and other pleural diseases as well. They have recently published their findings in the journal Current Opinion in Pulmonary Medicine and have concluded that image-guided techniques are far superior to the traditional biopsy techniques.
Overview of the Study
When a patient presents with symptoms of mesothleioma, or another pleural disease, the physician will schedule a series of tests to determine the location and makeup of the (possible) disease as presented. Imaging tests will be used to identify the presence of specific physical signs of disease and a biopsy will be conducted for the removal and analysis of actual tissue samples. In cases where fluid from a pleural effusion can be extracted, this fluid can also be analyzed for the presence of malignant cells, but this kind of analysis does not provide the same diagnostic precision as does the analysis of a biopsy specimen. Thus, a definitive diagnosis requires efficient biopsy techniques for the extraction of tissue.
Traditional pleural biopsies have been conducted through either thoracotomy or through “blind” biopsies of the parietal pleura. The former technique provides a clear path to the pleural cavity and the removal of tissue from it, but is a highly invasive procedure that features significant patient burden. A blind biopsy is a much less invasive procedure and can be conducted as an outpatient procedure, but its accuracy is limited because the physician will make the insertion, and subsequent tissue extraction, from outside the patient’s body, without any tools guiding him or her to specific locations in the pleural cavity.
Recent innovations in diagnostic techniques have led to the development of new procedures for diagnosis. Image-guided biopsy refers to the use of imaging technologies to guide the physician in his or her biopsy procedure. Ultrasound and CT are two of the most common technologies used to do this. Ultrasound is beneficial because its feedback is delivered in real time, while CT offers higher resolution than ultrasound does and is able to image structures that ultrasound is not able to. Another recent innovation is video-assisted thoracoscopic surgery, or VATS for short. VATS is a minimally invasive procedure where small incisions are made in a patient’s side and a tiny video camera and specific surgical instruments are inserted. The camera allows the doctor to see the interior landscapes of the patient’s thorax, while the instruments allow whatever procedure is required to be completed. In our discussion here, the instruments would be whatever tools were selected for the biopsy, but VATS can be used for a number of other procedures as well.
In their study, the authors investigated the sensitivity and efficacy of blind biopsy vs. image-guided biopsy in the diagnosis of both pleural malignancies and benign pleural diseases, such as pleural tuberculosis.
Results
The authors found that image-guided biopsy was much more effective in the diagnosis of mesothelioma and other pleural diseases than was blind biopsy. Image-guided techniques allow the physician to choose a location from which to make the extraction, which enables the doctor to select areas that are already displaying signs of disease. This ability significantly cuts down on the chances of a false negative due to poor selection of a sample site. The authors state that their research indicates blind biopsy techniques achieve a diagnostic rate of, at best, 50%, while image-guided techniques demonstrate a success rate well over 80%.
The authors also compared the applicability of image-guided biopsy to that of VATS, or to other thorascopic techniques that doctors may currently use, and they concluded that both sets of techniques exhibited similar diagnostic accuracy, but that the choice of which procedure to deploy should be based on patient status. VATS allows both diagnostic and therapeutic procedures to be performed, but is limited by a need for a clear separation of the pleurae and the presence of pleural fluid to facilitate entry, while image-guided biopsy is a purely diagnostic procedure, but one that can performed in the presence of a fused parietal and visceral pleura. They state that patients who present with large pleural effusions and the need for drainage or pleurodesis should undergo VATS, while patients who present without therapeutic needs, small effusions, and/or with conditions that complicate VATS should undergo image-guided biopsy.
Another consideration that the authors discussed regarding choice of procedure had to do with the potential of mesothelioma to invade biopsy sites, which the disease has a tendency to do. They state that the diagnostic accuracy of a procedure increased with its invasiveness, but so did the chances of the malignancy spreading to the biopsy site. They quote a study that concluded thoracotomy was associated with the highest diagnostic accuracy (100%), but also the highest rate of “tumor-seeding,” (24%), while image-guided was associated with a slightly less accurate diagnostic sensitivity (86%), but a smaller seed potential (5%). However, they state that larger studies are needed before a firm conclusion can be drawn.
Conclusion
The authors conclude their article by recommending that image-guided pleural biopsy, or another innovative procedure such as VATS, should replace blind pleural biopsy whenever possible. They state that it has a much higher diagnostic accuracy than does traditional biopsy, and is safe and effective for the investigation of mesothelioma, and other pleural diseases.
Labels: diagnosis, mesothelioma
posted by Belluck & Fox at 4:51 PM