Electrifying Brain Tumors

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Engelhard, who is a primary investigator on the study and has a number of patients in the NovoCure trials, became interested in the technology because it was something totally different and less toxic than traditional methods. "Surgery removes the malignant cells, radiation therapy exploits a difference in susceptibility to radiation between normal and cancer cells, chemotherapy exploits the fact that the cells are dividing, and this is a fourth way to exploit a difference between normal cells and cancer cells, namely the fact that the cancer cells have to physically split into two cells," Engelhard says. "It's using a completely different biological property of cancer cells as their Achilles heel."

Such a novel perspective came from Palti's background in biophysics. "I looked at electrical fields rather than chemical reactions," Palti says. "I suddenly realized that dividing cells should behave very differently under electrical fields of specific frequencies. So I sat down and did some modeling and ended up doing experiments in my basement."

"What he's doing is rather new," says David Cohen, an associate professor in radiology at Harvard Medical School. "Usually, electricity is passed through the skin to talk to the nerves and muscles. But this electricity alternates so quickly that it can't affect nerves and muscles--it goes back and forth so many times that the nerves see zero effect. But the dividing cells, they know about it." Cohen has closely examined the biophysics behind the phenomenon and notes that "the physical explanation for how the system works is sound. It's not a shot in the dark; it's carefully planned, carefully evolved work."

Perhaps the largest drawback to the NovoCure device is the battery that patients must lug with them wherever they go. In order for it to work, patients have to carry the battery around until the cancer has disappeared--as long as 24 months. (One patient, whose tumor has stopped growing but has not disappeared, has been using the device continuously for more than three years.) "Anybody would like to have a cure for brain tumors, that's for sure," says Mary Lovely, a medical information specialist at the National Brain Tumor Society. "When it starts to decrease quality of life because you're carrying it around, that's when it might not work anymore."

Engelhard says the current device is more a prototype than a final design. "First, we have to prove that it increases patient survival," Engelhard says. "Then modifications of the device might be made to make it easier for patients to participate in the treatment."

Novocure has high hopes. Because the electric-field effects appear to work across all cancers, at least in vitro, the company is interested in applying it to as many different disease types as it can. Although they also have "outstanding data" from a pilot trial in women with breast cancer, Novocure Board Chairman Bill Doyle notes, "We've focused our initial efforts on cancer where there is very poor long-term survival." Glioblastomas and lung cancer fit the bill, and Doyle says that pancreatic cancer could be next. "Our hope is that we will take on another cancer, and then another, and then another over the years."