A biopsy is a technique used for mesothelioma diagnosis which involves extracting a small sample of the fluid or tissue from the affected area which is examined by the pathologist. This fluid or tissue is removed with the help of a thin needle inserted into the affected area.



During the course of mesothelioma diagnosis, the first biopsy is done by removing the fluid around the lungs. Sometimes the doctors might do a tissue biopsy instead of a fluid biopsy to get better result. Laparoscopy or thoracoscopy are also conducted during mesothelioma diagnosis when a small incision is done and a tiny camera is inserted to the affected area to get a picture of the affected place. Also a small tissue sample is removed to analysis the tissue by a pathologist.

Depending on the affected area, the biopsy during mesothelioma diagnosis can be conducted in different ways:

Thoracoscopy - If the cancer is present in the pleura, a thoracoscope is inserted through a small incision through the chest wall to get a tissue sample. If fluid is accumulated in the chest, the doctor drains out the fluid by putting a needle into the chest and use gentle suction method to remove the fluid. This process is called thoracentesis.

Peritoneoscopy - If the cancer is present in the abdominal cavity, a peritoneoscope is used to get a sample tissue for further examination. If fluid is collected in the abdomen, doctor drains the fluid out of the body by putting a needle into the abdomen and using gentle suction to remove the fluid. This process is called paracentesis.

Once the mesothelioma diagnosis is confirmed by pathological examination and a pathologist issues a pathology report. The following tests can be conducted, if the doctor recommends further examination.

Video-Assisted Thoracoscopic Surgery (VATS) – this technique is widely used in mesothelioma diagnosis. In this technique various biopsies of pleural lining, nodules, masses and pleural fluid can be done with minimally invasive procedure along with other therapies done alongside like pleurodesis for pleural effusions. Several small ports or incisions are done through the chest wall wherein small camera is inserted and other instruments are used to take samples of tissue. With the help of a video screen showing the camera images, the surgeon can complete all necessary procedure. This procedure is a more viable option as compared to thoracotomy which involves larger incision to reach the chest cavity.

Immunohistochemical Markers for Mesothelioma

A diagnosis of any kind of cancer also involves a process where other forms of cancers are ruled during the course of diagnosis. Even in the case of mesothelioma, the most common “differential diagnosis” is between that of adenocarcinoma and mesothelioma. During the biopsy procedure, once the surgeon removes the tissue samples, it is sent to the pathologist at the laboratory for further examination. Here slides are made of the tissues and then viewed under the microscope by the pathologist.

Then an examination is done describing the tissue, which is then placed in a plastic cassette using fixative to preserves the tissue permanently. Once the tissue has been fixed permanently, paraffin blocks are made which allows the pathologist to slice off thin microscopic sections which is then stained to verify the patient's diagnosis.

Immunohistochemistry is a process of examining and recognizing cell types based on the binding of antibodies to specific components of the cell. Through this process the disease is diagnosed as mesothelioma or adenocarcinoma (or any other kind of cancer).