By JENNIFER CORBETT DOOREN, A non-invasive medical device that could provide a new way to battle brain cancer is being tested on patients with the most lethal form of the disease.

Researchers discussed details of the portable, non-invasive device, designed to blast apart cancer cells using an electrical field, at the American Society of Clinical Oncology's annual meeting.

Designed to disrupt the division of cancer cells in the brain, the device—the "Novo TTF" (TTF stands for "tumor-treating fields")—delivers alternating electrical fields to the cancer cells by means of insulated electrodes on the surface of the scalp. The four electrodes, each covered with a bandage, are worn under a white cap.

The device, from NovoCure Ltd., a closely held company based in Haifa, Israel, is being developed for patients with glioblastoma, a common form of brain cancer. It is approved for use in Europe. Patients diagnosed with glioblastoma typically undergo surgery to remove as much of the tumor as possible, then receive radiation and chemotherapy. Many also receive Roche's Avastin, a drug designed to block the growth of blood vessels that cause tumor growth.

Although some doctors at the oncology meeting said NovoCure's device holds potential as a treatment, especially after standard therapies fail, others were skeptical. "I think the technology is interesting, but I think it's totally unproven," said Henry Friedman, a professor of neuro-oncology at Duke University, Durham, N.C.

Some 22,000 cases of brain and central nervous system cancer will be diagnosed in the U.S. in 2010, according to the American Cancer Society. Doctors say glioblastomas are the most lethal type of brain cancer and hard to treat. Most patients die within five years of diagnosis; after initial treatment, many patients don't survive much longer than six months once a tumor resumes growing.

The device's electrical fields don't affect healthy brain cells, which don't divide, says Eilon Kirson, NovoCure's head of research and development. The main side effect is scalp irritation. Powering the device is a battery pack worn in an over-the-shoulder bag that's a bit smaller than a laptop computer. Patients are connected to the device for 20 hours a day.

A NovoCure-sponsored study involved 237 patients with advanced brain cancer in Europe and the U.S. who were previously treated with standard therapies. About half got the NovoCure device, and the other half got more chemotherapy. Patients on the device lived about 6.6 months, compared with 6 months for those on standard therapy. The difference isn't considered statistically significant.

Roger Stupp, a researcher who presented data at the oncology meeting and who leads a brain-tumor clinic at the University of Lausanne Medical Center in Switzerland, said patients on the device had significantly fewer side effects than chemotherapy patients. About 17% of patients on the device reported a rash under the electrodes.

Dr. Stupp said when NovoCure first approached him a few years ago to discuss the device, he thought the idea was "completely voodoo, goofy, nuts." But after a physicist colleague told him the use of electrical fields to interfere with dividing cells in the body was plausible, Dr. Stupp agreed to help design and participate in the clinical study.Dr. Kirson said NovoCure plans to meet soon with the U.S. Food and Drug Administration to discuss the filing of an application for approval. The device also is being studied in a clinical trial of newly diagnosed glioblastoma patients in multiple locations.

Gerry Bagnowski, 59, a gym teacher and coach at a Chicago elementary school, was diagnosed with glioblastoma in June 2009. He had surgery to remove the tumor at the University of Illinois, Chicago and got radiation treatment. The university invited him to participate in the study while getting chemotherapy. He was "scared, he recalled, but also considered himself "a dead man walking." He said he was willing to try anything to keep his tumor from growing back. Mr. Bagnowski wears a baseball cap over the device's electrode cap and disconnects from it when doing yard work or hitting golf balls at the driving range. He says he has successfully passed through airport security twice since receiving the device in September 2009.

Herbert Engelhard, an associate professor of neurosurgery overseeing the Novo TTF study at the University of Illinois, says current treatments simply slow the progression of glioblastomas; new treatments are needed to get rid of tumor cells completely. The current study aims for 283 patients at 12 centers in the U.S. and nine in Europe. Two-thirds of the patients will receive continuous therapy with the NovoTTF plus standard treatment, while one-third will get the standard treatment alone.