LOS ANGELES--In the first positive randomized US trial of hyperthermia in cancer, glioblastoma multiforme (GBM) patients who received hyperthermia in addition to bra-chytherapy survived significantly longer than those who did not get the heat treatment, Penny K. Sneed, MD, said at the American Society for Therapeutic Radiology and Oncology (ASTRO) meeting.
The patients who received hyper-thermia for 30 minutes before and after a brachytherapy boost survived a median of 85 weeks vs 76 weeks for those getting brachytherapy alone. When analyzed by intent to treat, the survival difference remained significant (80 weeks for hyper-thermia vs 76 weeks for controls).
The probability of 2-year survival was 31% for heat-treated patients vs 14% for the control group.
The phase II/III study from the Departments of Radiation Oncology and Neurological Surgery at the University of California, San Francisco, involved 112 adult patients who were eligible for brachytherapy after surgery and conventional radiotherapy; eligible patients had a unifocal, circumscribed, supratentorial glioblastoma of 5 cm or less in diameter.
Three-three patients were not randomized, primarily due to tumor progression during conventional radiotherapy, leaving 40 patients randomized to hyperther-mia and 39 to the control group. "For a variety of reasons, not all of the randomized patients proceeded with treatment as per the protocol," Dr. Sneed said.
In the end, 33 of the no-heat patients had brachytherapy implants, as did 36 of the heat-treated patients; thus, the results were analyzed both by intention to treat and according to those who actually received brachytherapy. Furthermore, four patients in the hyperthermia arm did not receive heat treatments but were analyzed on the heat arm.
The median freedom from progression was 33 weeks for the brachytherapy patients in the no-heat arm versus 49 weeks for those in the heat arm, a significant difference. Although there were more toxicities on the heat arm, most of these were mild neurologic toxicities that were fully reversible, or partial seizures, she said.