Malignant plural mesothelioma (MPM) is a highly aggressive form of lung cancer that is as resistant to cure as it is difficult to diagnose. MPM presents almost exclusively in individuals who have had environmental contact with asbestos, and onset of the disease can occur many decades after such exposures. MPM generally presents with cancer-like symptoms only at an advanced stage, at which time no wholly curative treatments are available.
Early Detection is Key to Life Extension
Individuals who have experienced environmental exposures to airborne asbestos fibers are considered to be at a high risk for MPM—these individuals should have regular medical screenings to detect the disease. While a cure for advanced cases of MPM still proves to be elusive, if detected early, there are several treatments that can extend the life of mesothelioma patients. These treatments are briefly outlined below:
- Chemotherapy: Present day chemotherapies for MPM center almost exclusively
around the combined administration of the two drugs pemetrexed (Alimtra)
and cisplatin. Usually indicated for patients who are not considered
to be candidates for surgery (lung resection), the preceding adjuvant
chemotherapy has resulted in tumor reduction in approximately 40% of
MPM patients who achieve a median, post- chemotherapy survival time
of 12 months.
While some cancers are vulnerable to chemotherapies subsequent to surgical tumor resection (reduction), MPM resists this dual therapy approach. Researchers are hopeful that a new class of novel, targeted, kinase inhibiting agents will prove to be as effective in MPM patients as they have been in the laboratory. Human clinical trials have just begun on the experimental tyrosine kinase inhibitor, dasatinib, a drug that can be taken orally and is expected to have minimal side-effects.
- Radiation Therapy (RT): MPM can be a difficult disease to treat with radiation, partially because of its usual close proximity to radiation sensitive organs such as the liver and kidneys. Because of concerns about overly broad patient exposures to radiation, a new form of RT known as Intensity-Modulated Radiation Therapy (IMRT) is now being used to treat post-operative MPM tumors. This new form of RT is being used in several U. S. cancer centers and it utilizes multiple beams of radiation that are focused in a unique way to mimic the precise shape of a tumor, thus limiting radiation exposures to the malignant mass only. IMRT provides oncologists with a new RT tool that has been shown to have a significant effect on recurrence of the disease. While the use of IMRT is still in its infancy, early results have given those who treat MPM cause for hope that the therapy will be an important new weapon in the battle against this asbestos-caused cancer.
- Surgery: Curative surgical interventions for MPM includes a highly
invasive and extensive procedure that involves the entire removal of
a tumor involved lung, as well as the plura, diaphragm, and pericardium.
Reconstruction of the diaphragm and pericardium are performed during
the surgery, which is known as extraplural pneumonectomy (EEP). EEP
surgery is limited to MPM cases where the disease has not spread beyond
the chest wall, an accurate evaluation of which is not easy to achieve.
A less extensive form of MPM surgery is known as plurectomy/decortication (P/D), where the lining of the lung (plura) is peeled away while leaving the lung intact. P/D surgery is rarely used due to the fact that the surrounding lung tissue is usually disease involved. Both EEP and D/P interventions have, to date, been of limited value when it comes to significant life extension in the MPM patient.
- Palliative care: A broad range of medical and non-medical interventions
that are designed to increase the quality of life for the terminally
ill MPM patient. Pain
and symptoms control, as well as a wide variety of counseling services
related to end of life issues are provided by palliative care professionals.