A surprising finding in a new JAMA study: adding alternating electrical-field application to standard chemotherapy (temozolomide) leads to a small, but significant, benefit in terms of progression-free and overall survival.
The study was a team effort, involving no less than 30 researcher-co-authors from 25 medical centers worldwide. The lead author is Roger Stupp MD of the Universities of Zurich and Lausanne, Switzerland.
Tumor treating fields (TTFs) are, as per the study authors, "... an antimitotic (reduces cell division) treatment that selectively disrupts the division of cells by delivering low-intensity, intermediate-frequency (200 kHz) alternating electric fields via transducer arrays applied to the shaved scalp."
There are several theories as to how and why such alternating superficially-applied current might help to retard the growth of cancer cells, but they remain unproven, although other studies have shown some benefit from their use.
The study involved 695 patients initially ("intent to treat") with the most lethal form of brain cancer, glioblastoma multiforme. The current report was an interim analysis of data from 315 patients who were randomly divided into two groups: 210 in the chemo plus TTFs group, and 105 in the chemo-only group.
In this study, the median follow-up was of 38 months (range, 18-60 months). Median progression-free survival in the intent-to-treat population was 7.1 months in the TTF plus temozolomide group, vs. 4.0 months in the temozolomide alone group, which represents a 38 percent improvement. Median overall survival in the per-protocol population was 20.5 months in the TTF plus temozolomide group (n = 196) and 15.6 months in the temozolomide alone group (n = 84) a 36 percent advantage.
The authors conclude that their interim analysis of 315 patients with glioblastoma who had completed standard chemoradiation therapy shows that adding TTFs to maintenance temozolomide chemotherapy significantly prolonged progression-free and overall survival.
Glioblastoma is a terrible disease, intractable and universally lethal. While adding TFFs to standard chemo-radiotherapy is hardly a cure, those few extra months can be a valuable benefit to those facing life's end and for their families. And the side-effect profile is essentially nil, so this seems like a small win-win immersed in a big loss, that of brain cancer.
