That word comes from a new study published in the European Journal of Cancer. Doctors from France, Belgium, the UK, and the Netherlands developed models showing how progression-free survival could be used for prognosis.
To independently validate these models, the researchers examined patient data from 10 European Organisation for Research and Treatment of Cancer (EORTC) studies of chemotherapy for malignant pleural mesothelioma. A total of 523 mesothelioma patients were included in the analysis. Researchers looked at the treatment response rate, progression-free survival at 9 and 18 weeks, and overall survival for each patient.
In the validation study, 28.4% of mesothelioma patients achieved either complete or partial disease response with first-line chemotherapy meaning that their mesothelioma tumors were reduced in size. In 77.8% of cases, chemotherapy temporarily stopped the mesothelioma tumors from growing.
When researchers compared the overall survival of patients with whether or not their mesothelioma had progressed at either 9 or 18 weeks, they found that lack of progression at these points correlated strongly with better overall survival.
In the published report of their findings, lead investigator Baktiar Hasan of the European Organisation for Research and Treatment of Cancer Headquarters in Brussels writes, “PFSR-18 [progression-free survival rate at 18 weeks] was strongly correlated and discriminated patients with better OS [overall survival] from the poorer prognosis patients. An earlier end-point, PFSR-9 [progression-free survival rate at 9 weeks] was also strongly correlated to OS with better discriminating capacity.”
Pleural mesothelioma is a malignancy of the membrane that surrounds the lungs. It is almost always caused by exposure to asbestos dust. Because the disease is highly resistant to all known cancer treatments, most patients do not survive longer than about 18 months after diagnosis.
Hasan, B et al, “Progression free survival rate at 9 and 18 weeks predict overall survival in patients with malignant pleural mesothelioma: An individual patients pooled analysis of 10 European Organisation for Research and Treatment of Cancer Lung Cancer Group studies and an independent study validation”, August 21, 2014, European Journal of Cancer Epub ahead of print