Biphasic mesothelioma accounts for 30 to 40 percent of all cases of malignant mesothelioma. It is a mix of the other two mesothelioma cancer subtypes, epithelioid and sarcomatoid.
The three histological categories, or cell types, for mesothelioma have their own distinguishing characteristics when viewed under a microscope.
Epitheliod mesothelioma comprises cells with a uniform, cube-like shape. Sarcomatoid mesothelioma comprises cells with a spindle shape. Biphasic mesothelioma doesn’t have its own unique cell structure, but its tumors are a combination of epitheliod and sarcomatoid cells.
Diagnosing the Disease
Mesothelioma is diagnosed through physical exams and the use of imaging tests. Other tests performed include blood counts, bronchoscopy, sedimentation rate, and biopsies.
For a cancer as specific as biphasic mesothelioma, in order for a proper diagnosis, other types of cancer with similar characteristics such as synovial sarcomas and carcinomas must first be ruled out. Techniques to identify and label specific proteins in cells, such as an immunohistochemistry test, can be performed in order to distinguish this disease from other cancers.
Since the cells are very small and both the sarcomatoid and epithelial cells have the ability to exist in different areas of the tumor, it is hard to diagnose and detect biphasic mesothelioma. The best way to make sure that a diagnosis is correct is to evaluate a substantial amount of tissue from the affected area.
Treating the Disease
Treatment for malignant biphasic mesothelioma may vary depending on the ratio of sarcomatoid to epithelial cells present. Since sarcomatoid mesothelioma is typically more aggressive than epithelial mesothelioma, patients diagnosed with biphasic mesothelioma with lower levels of sarcomatoid cells tend to have a better prognosis. There are two types of treatment:
Traditional Treatments – Traditional treatments include chemotherapy, radiation, and surgery. Often several treatments are used in combination to make a trimodal approach for better results and longer survival rates. The treatment combinations chosen depend on the stage of the cancer.
The type of surgery that may be performed as treatment for malignant mesothelioma includes aggressive procedures like the removal of the infected part of the lung and the chest lining that surrounds it. Less drastic is a procedure to drain the fluid around the lung that causes pain and pressure.
New Treatments – Some of the newer malignant mesothelioma treatments include gene therapy, immunotherapy, photodynamic therapy (PDT), new chemotherapy agents, and modulated radiation therapy (IMRT). These treatments are not as successful as the traditional treatments, but they are being used along with traditional treatments and the results are closely monitored.
Additional Treatment Methods
Other more treatments for malignant biphasic mesothelioma are being tested in clinical trials such as angiogenesis therapies, antineoplaston therapy, and interferon and interleukin therapy. Researchers are also studying the effectiveness of alternative treatments like the use of herbs, special diets, acupuncture, homeopathic medicine, large doses of vitamin C, and therapeutic massage.