Saturday, June 20, 2009

Mesothelioma Diagnosis

Mesothelioma is not always diagnosed because the cancer is still unrecognizable. A mesothelioma diagnosis may often be classified as another condition because the symptoms are similar to those of other illnesses. Even today, a mesothelioma diagnosis can be classified as lung cancer, which is an entirely different disease. Mesothelioma is a cancer of the lining of the chest, lung, and abdominal cavity and has been linked to high levels of workplace and non-occupational exposure to asbestos. (See Mesothelioma Prognosis)

A mesothelioma diagnosis most commonly begins with a complete medical history review and physical examination of a patient who suffers from mesothelioma symptoms and signs including shortness of breath, chest pains, swollen abdomen, and more. The physical exam should involve a number of imaging tests to search for suspicious cell formation. These tests may include:

X-rays Chest or abdomen x-rays can reveal fluid build-up, masses, or signs of non-cancerous pleural disease.

Computed Tomography (CT) Scan A series of detailed images of the body. CT scans can locate pleural disease, chest wall invasions, and can guide fine needle aspiration tests. However, CT scans cannot differentiate between benign or malignant mesothelioma.

Magnetic Resonance Imaging (MRI) MRI scans use a computer-linked magnet to photograph details of the inside of the body and can determine the severity of a tumor.

Positron Emission Tomography (PET) PET imaging tests have become one of the most efficient ways of diagnosing mesothelioma tumors as well as determining the staging of the cancer.

Biopsy A needle biopsy is almost always necessary to confirm a mesothelioma diagnosis. In a biopsy, a sample of tissue is removed and examined under a microscope to test for cancer cells. Depending on the location of the abnormal area, a biopsy can be done in different ways including:

Thoracoscopy - If the cancer is located in the pleura, a small incision will be made through the chest wall and a thoracoscope will be inserted to obtain a tissue sample.

Peritoneoscopy If the cancer is in the abdominal cavity, a doctor will use a peritoneoscope to obtain sample tissue for further examination.


Mesothelioma is a form of cancer that is almost always caused by exposure to asbestos. In this disease, malignant cells develop in the mesothelium, a protective lining that covers most of the body's internal organs. Its most common site is the pleura (outer lining of the lungs and internal chest wall), but it may also occur in the peritoneum (the lining of the abdominal cavity), the heart,[1] the pericardium (a sac that surrounds the heart) or tunica vaginalis.

Most people who develop mesothelioma have worked on jobs where they inhaled asbestos particles, or they have been exposed to asbestos dust and fiber in other ways. Washing the clothes of a family member who worked with asbestos can also put a person at risk for developing mesothelioma.[2] Unlike lung cancer, there is no association between mesothelioma and smoking, but smoking greatly increases risk of other asbestos-induced cancer.[3] Compensation via asbestos funds or lawsuits is an important issue in mesothelioma (see asbestos and the law).

The symptoms of mesothelioma include shortness of breath due to pleural effusion (fluid between the lung and the chest wall) or chest wall pain, and general symptoms such as weight loss. The diagnosis may be suspected with chest X-ray and CT scan, and is confirmed with a biopsy (tissue sample) and microscopic examination. A thoracoscopy (inserting a tube with a camera into the chest) can be used to take biopsies. It allows the introduction of substances such as talc to obliterate the pleural space (called pleurodesis), which prevents more fluid from accumulating and pressing on the lung. Despite treatment with chemotherapy, radiation therapy or sometimes surgery, the disease carries a poor prognosis. Research about screening tests for the early detection of mesothelioma is ongoing.