The overwhelming majority – approximately 80 percent – of mesothelioma patients have a prolonged history of inhaling asbestos fibers or dust, normally varying between 20 and 50 years before diagnosis. The disease predominantly strikes men between the ages of 60 and 80. Most of those men worked in heavy industry, specifically pipefitters, shipbuilders, plumbers and steamfitters-all areas which, in the past, have subjected workers to heavy asbestos exposure. The presentation is nonspecific and it can be a major challenge for the doctor(s) to come up with an accurate diagnosis.
In the case of pleural mesothelioma, the first indication a patient may have that something is wrong is usually a progressively-worsening shortness of breath or a steady chest wall pain. The shortness of breath is usually related to a large pleural effusion, or a buildup of fluid on the pleural cavity; the chest pain is normally caused by a major chest wall invasion. Other initial indications could include a dry cough, fever, night sweats, fatigue and weight loss, though these normally occur later.
Due to the fact mesothelioma tends to form in the body cavities, it is likely to have done significant damage before the patient seeks medical attention. Though an initial diagnosis of mesothelioma can be made quickly, it may take up to three months for an official diagnosis to be made. In many cases, mesothelioma is discovered accidentally though a routine chest X-ray.
The tell-tale signs of mesothelioma on an X-ray is the presence of fluid and pleural thickening several centimeters in diameter. In most instances, the cancer is found in one lung; in the majority of cases, it is located in the right lung. A large majority of patients also have abnormalities discovered when an EKG test is performed. A number of new methods intended to diagnose pleural mesothelioma are under development, but have yet to produce impressive results.
Once the diagnosis of pleural mesothelioma is confirmed, the spread of the cancer can be monitored by either magnetic resonance imaging or a CT scan.
Patients diagnosed with pleural mesothelioma usually survive between 10 and 17 months between the initial onset of systems and nine to 13 months from formal diagnosis. The three-year survival rate is estimated to be about 10 percent, while the five-year survival rate varies between 3 and 5 percent.
Patients suffering from peritoneal mesothelioma normally suffer from abdominal distention with ascites. They can also suffer from bowel obstruction, masses in their abdomen and pelvis, nausea and vomiting. Other symptoms include a fever, hernia, edema of the lower extremities and obstructive uropathy.
Peritoneal mesothelioma can be more difficult to diagnose, requiring a direct biopsy by laparotomy or peritoneoscopy to be found in many cases. Once the diagnosis is made, CT scans or ultrasound can be used to view the tumors and fluid buildup. Peritoneal mesothelioma moves more rapidly than pleural mesothelioma and the survival time from first symptoms to death is correspondingly less. The median survival time from the onset of symptoms is 10 months, while the survival time from diagnosis is an estimated seven months.