A device attached to a patient's scalp that delivers a continuous dose of low-intensity electric fields improves survival and slows the growth of a deadly brain tumor, according to a new clinical trial led by a Northwestern Medicine scientist and published Dec. 19 in the journal JAMA.
The new treatment for glioblastoma uses alternating electric currents called tumor-treating fields (TTFields), which are delivered through an array of insulated electrodes that are affixed to a patient's shaved scalp.
Except for occasional breaks and weekly electrode changes, patients wear the device at all times. The electrodes are connected via a cable to a small battery-powered device and continually deliver an electrical field to brain tissue.
Combining the TTFields therapy with standard maintenance chemotherapy allowed for a significant improvement in both progression-free and overall survival in patients with recently diagnosed glioblastoma.
Patients who received TTFields did better than patients who did not: the median survival time for those receiving the TTFields therapy was 20.9 months versus 16.0 months for patients who did not, with a substantially higher fraction of patients alive at two, three or four years after diagnosis.
"This trial establishes a new treatment paradigm that substantially improves the outcome in patients with glioblastoma, and which may have applications in many other forms of cancer," said lead study author Dr. Roger Stupp, professor of neurological surgery and of medicine at Northwestern University Feinberg School of Medicine and Northwestern Medicine chief of neuro-oncology in the department of neurology.
"With TTFields therapy combined with radiation and temozolomide chemotherapy, up to 43 percent of glioblastoma patients will survive longer than two years," Stupp said. "In a disease where, until 2004, the great majority of patients died within one year, this is yet another example how systematic and interdisciplinary research will benefit patients in everyday care."
Stupp also is co-director of the Lou and Jean Malnati Brain Tumor Institute at Northwestern Medicine and a neuro-oncologist at Northwestern Memorial Hospital and the Robert H. Lurie Comprehensive Cancer Center of Northwestern University.
Previous research had demonstrated that TTFields will inhibit tumor growth and selectively affect dividing cells, ultimately leading to cancer cell death and tumor growth inhibition.
In the study, 695 patients were randomly assigned to either receive the TTFields in combination with temozolomide, a chemotherapy drug, or the chemotherapy drug alone. Overall, 466 patients received the TTFields-chemotherapy combination, and 229 received the chemotherapy treatment alone.
There was no difference in the rate of adverse events between the two groups, except for mild to moderate skin irritation on the scalp, which was experienced by slightly more than half of patients receiving the TTFields therapy.