ASCO 2014: Addition of Chemotherapy to Radiotherapy Improves Survival in Low-Grade Glioma
In a long-term follow-up analysis of RTOG 9802, the addition of PCV (procarbazine [Matulane], lomustine [CeeNu], and vincristine) to radiotherapy prolonged both progression-free survival and overall survival in adult patients with low-grade glioma. The findings were reported at the 2014 ASCO Annual Meeting in Chicago (Abstract 2000).
“On average, patients who received PCV lived 5.5 years longer than those who received radiation alone,” said Jan Buckner, MD, Deputy Director of Cancer Practice at Mayo Clinic Cancer Center, who presented the study.
Study Details
The phase III RTOG 9802 trial randomly assigned 251 patients with supratentorial grade II astrocytoma, oligoastrocytoma, or oligodendroglioma to radiotherapy alone or radiotherapy followed by six cycles of PCV chemotherapy. Eligible patients were age < 40 years with subtotal resection or age ≥ 40 with any extent of resection.
Outcomes
Initial results of RTOG 9802, published in the Journal of Clinical Oncology in 2012, demonstrated that radiotherapy plus PCV prolonged progression-free survival, but not overall survival, when compared to radiotherapy alone at 5.9 years follow-up.
In the current analysis, with a median follow-up of 11.9 years, the median overall survival was 13.3 years for patients in the radiotherapy plus PCV arm and 7.8 years in the radiotherapy alone arm (HR = 0.59, P = .03). Five- and 10-year overall survival rates for radiotherapy plus PCV vs radiotherapy alone were 73% vs 64% and 62% vs 41%, respectively. Median progression-free survival was 10.4 years in the radiotherapy plus PCV arm vs 4.0 years in the radiotherapy alone arm (HR = 0.50, P = .002).
Investigators found that astrocytoma and astrocytoma-dominant oligoastrocytoma histology were prognostic indicators for worse overall survival (HR = 2.16, P < .001) and progression-free survival (HR = 1.85, P < .001). Male patients were also found to have worse overall survival, but not progression-free survival, compared to female patients (HR = 1.51, P = .02).
The study was sponsored by the Radiation Therapy Oncology Group. For full disclosures of the study authors, view the study abstract at abstract.asco.org.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
