Minesh Mehta, MD
The patient begins by shaving his head. He then places the 4 transducer arrays to his skull and turns on the low-voltage current, which courses through his brain for as long as the device is worn, with the recommendation being at least 18 hours a day, every day.
It may sound like dystopian science fiction, but the Optune system, with its tumor-treating electromagnetic fields, is actually one of the biggest advances in glioblastoma treatment in more than a decade.
It is also a particularly innovative example of a novel class of products for patients with cancer: wearable therapeutic devices.
Such devices have taken a comparatively long time to make any impact on oncology. Global sales of wearable health products, which were virtually nonexistent in 2010, reached $3.2 billion in 2015, according to industry analysts at Mordor Intelligence.1
Oncology-related devices were such a small portion of the total, however, that the healthcare analyst at one market research firm said in an email that he had never separated cancer from the rest of the field and that he doubted any of his counterparts would bother breaking out such a “niche” segment at this point.
The relative paucity of cancer wearables in past years stemmed from a variety of factors, but such products have begun to arrive in numbers that just might merit quantification by 2020, when Mordor expects wearable medical device sales to reach $7.9 billion.
Tumor-Treating Field for Brain Cancer
For the moment, the Optune system occupies a unique position. It is the only wearable product designed and approved to fight cancer directly rather than fighting the effects of the disease or the effects of cancer treatment regimens. The FDA has approved the device for patients with recurrent and newly diagnosed glioblastoma.
Yet although the Optune system is an entirely new category of cancer treatment, it operates upon a surprisingly simple principle.
Strands of DNA are dipoles; they have positive electric charges at one end and negative electric charges at the other. As a result, it is possible to make them line up in an orderly fashion—with all the positively charged ends facing the same direction and all the negatively charged ends facing the opposite direction—simply by running a current through them. Better still, it turns out, tumor DNA cannot divide normally and produce daughter cells when it is lined up in this manner.
Translating this observation into a product took far more time and effort than using better Bluetooth standards to build a stylish heart rate monitor. Nearly 15 years elapsed between the time when Israeli researcher Yoram Palti, MD, PhD, first hypothesized that low-voltage current could hinder tumor growth and the approval of the Optune system.
“A lot of people were pretty skeptical when they first heard the idea, but there’s just no ignoring the results.
In what’s known as the EF-14 study2
on patients with newly diagnosed glioblastoma, using the NovoTTF-100A in addition to chemotherapy after surgery and radiotherapy was associated with an approximate 5-month increase in median survival time,” said Minesh Mehta, MD, deputy director and chief of radiation oncology at the Miami Cancer Institute.
“It has been considerably more than a decade since any new treatment showed anything like that big an effect in glioblastoma patients,” he added. Of course, glioblastoma is a relatively rare tumor type, but tumor-treating fields may eventually help a large percentage of patients with cancer. The Optune system is being evaluated in clinical trials in other types of brain cancer,3
Mehta noted, as well as in early-stage trials in lung cancer4
and other tumors located in the chest.
“It is exciting to think that it could prove to be an entirely new weapon that works against a wide variety of tumor types, particularly because it is so well tolerated compared with other cancer treatments,” Mehta said. “It doesn’t cause pain other than some skin irritation. It doesn’t induce nausea. It doesn’t make patients weak. It just requires patients to apply a few transducer pads to the skin and carry a 3-pound device around. It obviously looks dramatic when it’s used on the head, but can be covered using hairpieces or headgear.”
Cooling Caps to Prevent Hair Loss
Unlike the Optune system, which requires users to sacrifice their hair, other wearable devices are designed to prevent patients with cancer from losing their hair while they undergo a more common type of treatment, chemotherapy.