Study Supports IDH Gene as Prognostic Marker in Anaplastic Astrocytoma
New findings suggest that a gene called IDH might be a prognostic marker for a rare form of brain cancer. Patients in this study who had a mutated IDH gene lived an average of 7.9 years after diagnosis vs. 2.8 years for patients with unaltered IDH.
The IDH study was part of the phase III clinical trial RTOG 9813, which involved 301 patients with anaplastic astrocytoma. The dualarm trial evaluated the effectiveness of radiation therapy plus either of two chemotherapy drugs: temozolomide and nitrosourea.
“We found that IDH status is not only a significant prognostic biomarker for the classification of anaplastic gliomas, but there appears to be a trend in the data that suggests that it might also be an important predictive biomarker for determining which type of chemotherapy patients should receive,” says study co-author Arnab Chakravarti, MD, professor and chair of the Department of Radiation Oncology at Ohio State, and a member of the Translational Therapeutics Program at the OSUCCC – James.
“If this novel finding is verified, it could have a critical influence on future patient care,” adds Chakravarti, who was the clinical trial’s translational research national
The trial showed no significant difference in survival in patients taking temozolomide compared with patients taking nitrosourea after a follow up of 3.6 years on average. However, the study also suggested a trend toward better survival for patients with mutated IDH who received radiation therapy plus temozolomide compared with patients receiving radiation therapy and nitrosourea.
Astrocytomas arise from astrocytes, or star-shaped cells that nourish and support nerve and blood-vessel cells in the brain. Anaplastic astrocytomas are grade III brain tumors that can become grade IV tumors, which are also called glioblastoma. Headaches, seizures, memory loss and behavioral change are early signs of the disease. Other symptoms can occur, depending on where in the brain the tumor develops.
These findings were presented at the 2015 American Society of Clinical Oncology annual meeting in Chicago.