Mesothelioma is a cancer which occurs within the cells of the chest and abdomen linings – the pleura around the lungs and chest, and the peritoneum around the abdominal organs. This type of cancer often results from exposure to asbestos. Although rare, it can be very deadly; the survival rate over five years is just 8%, although this is partially because the disease is usually discovered in its very late stages. (As with all types of cancer, the earlier the disease is discovered, the more likely it can be treated successfully.)
Fortunately for such a deadly disease, actual cases are relatively rare. Although there has been a slight increase in recent years, in most developed countries cases vary between and 1 and 30 cases per million people – just a few percent of the rate for lung cancer, for example. In developing countries where asbestos is still sometimes used in construction, however, malignant mesothelioma rates will likely continue to increase for some time.
The most important risk factor for mesothelioma is exposure to asbestos. However, the cancer itself may take several decades to develop. The first noticeable symptoms depend upon where the cancer begins. If it begins within the chest cavity (pleural mesothelioma), the first symptoms are usually caused by lung discomfort: coughing, shortness of breath, and chest pains. If it begins in the abdomen (peritoneal mesothelioma), symptoms often relate more to the digestive system: weight loss, abdominal pain, and anemia. Other symptoms can include fever, fatigue, coughing up blood, and bowel difficulties.
As the disease progresses, more serious symptoms can occur as the body struggles to cope with the disease. More severe symptoms include dangerous blood clots in the veins, internal bleeding within certain organs, jaundice (when the skin and eyes turn yellow), pleural effusion (fluid accumulating around the lungs), and ascites (fluid accumulating within the abdomen).
It should be noted that these symptoms are also caused by many other conditions, most of them non-serious: therefore, only a qualified medical diagnosis can confirm the presence of cancer. This diagnosis will also estimate how far the cancer has progressed, by identifying the first (and possibly only) tumour, and whether it has spread to the body’s lymph nodes (immune system).
Mesothelioma is usually treated with the same standard approaches employed against other cancers: radiation and chemotherapy. When mesothelioma is discovered in its first two stages (before or just after it has begun to spread from the initial tumour), the use of both therapies together has a 75% chance of forcing the cancer into remission.
Probably because of the cancer’s rapid spread through the cell lining in the body, however, surgery is not currently a common option alone – it has just a 15% chance of causing remission. The most common surgical strategy is to remove the chest lining (pleurectomy), and occasionally the lining around the lungs as well. This can be followed by radiation and chemotherapy treatments.
The most radical and likely most effective treatments for mesothelioma include combinations of surgery to remove cancerous cells, radiation treatment, and aggressive chemotherapy. However, chemical treatment alone may be of some benefit, particularly to patients who are not in sufficiently good health to undergo the other courses of treatment. Common drugs of choice include cisplatin and Alimta (pemetrexed). Raltitrexed was previously used in a similar capacity.