Additional Prognosis Information

Though general life expectancy for mesothelioma patients is low, there are many factors that contribute to the cancer’s prognosis – the outcome or course of the disease.

Type of Mesothelioma

In addition to the different locations of mesothelioma in the body, the cancer can also be classified by its histology – how the cancerous cells look under a microscope.   The most common type is called epithelioid mesothelioma, and luckily, it tends to have the best prognosis.  This type accounts for approximately 50-60% of all mesotheliomas.  Exact statistics for the life expectancy of the other types are difficult to come by, but a 2000 study in Thorax journal showed that the other three histological types of mesothelioma – sarcomatoid (fibrous, 10-20% of all mesothelioma tumors), mixed (biphasic, 30-40%), and demoplastic (rare) – generally have a poorer prognosis than the epithelioid type.

Resectability

If a tumor is deemed resectable, this means it can be removed by surgery.  Unfortunately, because of mesothelioma’s long latency period and frequent delay in diagnosis, surgery is rarely an option.  However, if the cancer is caught early enough and has not spread, surgery may be possible.  Minimally invasive procedures like thoracentesis or pleurodesis may help alleviate symptoms, but the cancer itself must be removed if there is any hope of extending life expectancy.  Depending upon the location of the tumor, the surgeon may perform a pneumonectomy (removal of the lung), a pleurectomy (removal of the tissue lining the chest or abdomen), or an extrapleural pneumonectomy (removal of the lung and surrounding pleural tissue).  Surgery, though not always possible, is thought to improve both prognosis and life expectancy.

Patient’s Health

The same study in Thorax journal identified other health factors associated with poor mesothelioma prognosis.  Weight loss, chest pain, leukocytosis (high white blood cell count), thrombocytosis (high platelet count), and low hemoglobin (red blood cell count) were all indicative of a poorer outcome.  However, good overall health – how well the patient could perform everyday activities – generally pointed to a more favorable prognosis.

Other Factors

Some other factors that may determine prognosis include:
  • Patient’s age – the younger the patient, the better the prognosis
  • Patient’s gender – male patients tend to have a worse prognosis
  • Size of the tumor
  • Stage of the cancer
  • How early the cancer is diagnosed

Current Prognosis Studies

In addition to the 2000 study, other research is exploring the factors that may point to improved or reduced life expectancy in mesothelioma patients.  A 2007 study published in Clinical Cancer Research examined mesothelioma sufferers for the presence of osteopontin and mesothelin, proteins found in bone and mesothelial tissue, respectively.  The scientists found that osteopontin was a good predictor of asbestos-related disease, but did not distinguish between malignant tumors and benign lesions.  Mesothelin, on the other hand, was a reliable indicator of malignant mesothelioma, but not its histological type.  The study concludes that both proteins are potentially valuable as prognostic tumor markers. In 2009, the Journal of Thoracic and Cardiovascular Surgery published the results of a study at Brigham and Women’s Hospital in Massachusetts, notable to mesothelioma patients for its Division of Thoracic Surgery.  Of the patients who were able to undergo both extrapleural pneumonectomy surgery and cisplatin chemotherapy, the predictors of greater life expectancy were receiving treatment at an early stage and testing negative for cancerous cells in the extrapleural lymph nodes. References:
American Cancer Society
Clinical Cancer Research
Journal of Thoracic and Cardiovascular Surgery
National Cancer Institute
Thorax: An International Journal of Respiratory Medicine