An innovative alternative to chemotherapy uses electric fields to disrupt tumor growth
By Nancy McVicar
The latest treatment for the most aggressive form of brain cancer is so new and so gentle on the patient that some people still consider it science fiction, says Dr. Jose Valerio, a neurosurgeon at Cleveland Clinic Florida in Weston.
The therapy, approved by the U.S. Food and Drug Administration, sends painless electric fields into the brain to disrupt the rapid cell division exhibited by cancer cells resulting in the death of those cells without harming healthy tissue.
Valerio has seen the treatment prolong the lives of patients who had the standard treatment for glioblastoma (also called GBM) – surgery followed by chemotherapy and radiation – who then had a recurrence of the tumor.
Some patients who have a recurrence of the disease are opting to take the new treatment called TTF (Tumor-Treating Fields) therapy instead of more chemotherapy, which can affect the entire body, not just the tumor.
“We have patients with close to one-year survival with this treatment,” Valerio says, “and their quality of life is not affected because there are no side effects.”
The treatment was developed by Novocure, headquartered in the British Isle of Jersey. Novocure’s U.S. operations are based in Portsmouth, N.H., and the company has a research facility in Haifa, Israel.
Valerio says the treatment was tested first on cancer cells in the lab and then in animals before clinical trials began in brain tumor patients. Results of the human studies published in the European Journal of Cancer showed TTF produced outcomes comparable to chemotherapy but with a better quality of life.
In January, the National Comprehensive Cancer Network, an alliance of the world’s 21 leading cancer centers, added TTF Therapy to its clinical practice guidelines for treatment of brain tumors and other central nervous system cancers.
Use of the treatment is expanding across the country and two other centers in South Florida – the University of Miami’s Sylvester Comprehensive Cancer Center and Neurological Associates of South Florida, Boca Raton, now offer it.
The treatment involves shaving the patient’s head and using insulated transducer arrays placed on the skin in the region surrounding the tumor.
“We do an MRI and a 3D reconstruction of where the brain tumor is, then do a mapping to find the best place to place the fields in the skull,” says Valerio of Cleveland Clinic Florida. The patient wears the device, which is attached to an external battery pack, 18 hours a day. The fields can be changed every 72 to 96 hours. They affect only the cancer cells attempting to divide and do not stimulate nerves or muscle or heat the tissue.
“Only 22 percent of any pill you take goes to the treatment, but with this, you have the full treatment without any side effects,” Valerio says.
About 10,000 people in the United States are diagnosed with glioblastoma each year, and survival rates are not good. The median survival from the time of diagnosis is 15 months, according to the National Institutes of Health.
Researchers continue to look for better treatments including the use of vaccines, and research refining the use of electric fields also is continuing.
TTF therapy is also being tried as another treatment option for both metastatic breast cancer and lung cancer, Valerio says.