Mesothelioma can be defined as the cancer of the lining tissue or mesothelium which surrounds the lungs, abdomen and heart. The main cause of mesothelioma is the exposure to asbestos, which is a cancer causing agent. When the minute fibers of asbestos are inhaled or ingested by a person they get into the lungs and stomach and in turn cause the cells of the mesothelium to multiply without any control. This condition is known as mesothelioma. These cancerous cells slowly start to damage other tissues and organs, causing more complications.

There are mainly three types of mesothelioma. These are:

• Pleural mesothelioma - which attacks the mesothelium of lungs
• Peritoneal mesothelioma - which attack the mesothelium of the stomach
• Pericardial mesothelioma - which attacks mesothelium of the heart.

People who work in asbestos mines, or live near asbestos mines, workers who handle asbestos materials, building workers, workers associated with the ship industry are more prone to develop mesothelioma. An early detection of mesothelioma can save the life, but unfortunately a diagnosis of mesothelioma is not easy. The symptoms of malignant mesothelioma appear only after a long period from the actual exposure. Misdiagnosis chances are more for mesothelioma as the symptoms of mesothelioma are similar to those of common cold or any other seasonal allergy or can be identified as lung cancer which is different from mesothelioma.

There are different techniques for diagnosing mesothelioma. If you suspect of any exposure to asbestos be sure to consult a physician and do the required tests. The physician will check for the common symptoms of mesothelioma like shortness of breath, mild to severe pain in the chest, sudden weight loss, pain and swelling in abdomen, presence of excess liquid surrounding the lungs etc. Imaging tests likeX-rays, CAT/CT scan, MRI scan, PET scan are done to determine the presence of cancerous cells in the body.
 

• Diagnosis using X-rays - An X-ray of the chest or abdomen helps a medical practitioner to see any abnormalities like fluid or tissue mass build up in heart, lungs and abdomen. The drawback of X-rays is that they sometimes fail to detect tiny growths caused in mesothelioma, delaying the diagnosis.
   
• Diagnosis of mesothelioma using CAT/CT scan – CAT and CT scans give a three dimensional image of the internal organs. They are able to produce extremely detailed pictures of organs, bones etc. CT scan provides cross sectional view of internal organs. This is more helpful in identifying the exact location of mesothelioma. But CT scans are unable to differentiate between benign and malignant masses.
   
• Diagnosis using MRI scans - The most sophisticated way to diagnose mesothelioma is through MRI scan. As they use magnetic resonance and radio waves to produce the pictures of internal organs, MRI scans are very clear and useful in detecting mesothelioma.
   
• Diagnosis using PET scans - Positron Emission Tomography is the widely used method for detecting mesothelioma. By using cameras and tracers, PET scans can produce images which indicate biological changes, including the minute cancerous cells.

Another diagnosis method for mesothelioma includes biopsy of the internal organ which is suspected to have tumor. Thoracoscopy is the procedure of taking a small tissue sample of lungs for biopsy. Peritoneoscopy is done to get samples of tissue from abdomen. The samples of tissues are then taken for biopsy. Biopsy is a close examination of the tissue under the microscope, and is usually done by a pathologist. So the final diagnosis of mesothelioma lies in the hands of the pathologist.