In a recent mesothelioma study published in the Japanese Journal of Clinical Oncology and conducted by Shuko Nojiri and colleagues at the University of Tokyo, the characteristics of survival for patients with malignant pleural mesothelioma were evaluated.
The study consisted of 314 pleural mesothelioma patients, which were examined using the Kaplan-Meier method with the logrank test. The Kaplan-Meier method estimates survival function from life-time data and measures the fraction of patients living for a certain amount of time after treatment. The logrank test is a hypothesis test used to compare survival distributions of two different samples.
Pleural mesothelioma is a rare form of cancer almost exclusively caused by asbestos exposure. Most cases of exposure occur by inhaling airborne asbestos fibers after asbestos-containing materials have been damaged. Because there are no immediate side effects after being exposed, many are completely unaware that any exposure has occurred.
The average mesothelioma life expectancy for patients ranges between four and 18 months after diagnosis. Unfortunately for most patients, symptoms associated with pleural mesothelioma can take as long as 20 to 50 years to arise, resulting in a diagnosis during the later stages of development. Such a late diagnosis often limits and complicates treatment options for those wishing to combat the cancer.
From the 314 patients studied, 223 (71 percent) passed away and 40 (13 percent) were still alive by the end of the observation period. A total of 51 (16 percent) patients were transferred to other hospitals before the end of the study period, yielding a median survival of 308 days (10 months).
The researchers concluded that characteristics providing a negative impact on survival included patients older than 70, non-epithelioid mesothelioma types, poor performance status, high white blood cell counts, and a high C-reactive protein level.
Additional information on mesothelioma may be found through the Mesothelioma Center.