Chemotherapy after radiation slows progression of low-grade gliomas
A chemotherapy regimen of procarbazine, lomustine (CCNU), and vincristine (PCV) administered after radiation therapy improved both progression-free survival and overall survival in adults with low-grade gliomas when compared to radiation therapy alone. These findings were part of a Phase III clinical trial presented at the Society for Neuro-Oncology 19th Annual Meeting in Miami, Florida (doi:10.1093/neuonc/nou237.13).
Gliomas, tumors that originate in the glial cells of the brain or spinal cord, are the most common form of primary brain tumor. The American Cancer Society estimates that 23,000 people will develop primary brain tumors in the United States in 2014 and 10% to 15% of these patients will have low-grade gliomas.
"On average, patients who received PCV lived 5.5 years longer than those who received radiation alone," said Jan Buckner, MD, professor of oncology at Mayo Clinic in Rochester, Minnesota. "These findings build on results published in the Journal of Clinical Oncology in 2012 and presented at the 2014 annual meeting of the American Society of Clinical Oncology, which showed that PCV given with radiation therapy at the time of initial diagnosis prolongs progression free-survival."
The trial, RTOG 9802, enrolled 251 patients with low-grade gliomas between October 1998 and June 2002 to investigate the role of chemotherapy following radiation treatment. The patients enrolled in this study were considered higher risk compared with other low-grade glioma patients because they were age 40 years or older, or had incomplete surgical removal of their tumor if they were younger than 40 years.
Investigators found that patients with oligodendroglioma had better outcomes than those with astrocytoma or oligoastrocytoma. Women had a better response to the treatment regimen than men.
"RTOG 9802 involved a network of investigators across the United States and Canada working through the National Cancer Institute's National Clinical Trials Network," Buckner said. "This trial could only have been conducted through a publicly funded national clinical trials network."