City of Hope physicians are using an electrifying new technology to treat cancer. Called the NanoKnife, the method sends a jolt of electricity through tumors, destroying cancer at the cellular level.

John Park uses the NanoKnife to electrify and kill tumors (Photo courtesy of John Park)

City of Hope is one of only two academic institutions in California and more than two dozen in the nation that can offer the technology to patients, according to John Park, M.D., Ph.D., chief of the Division of Interventional Radiology in the Department of Diagnostic Radiology.

He and his brother, Jinha Park, M.D., Ph.D., assistant professor in the department, along with Gagandeep Singh, M.D., interim chair of the Department of Surgery, and Joseph Kim, M.D., associate professor in the Division of Surgical Oncology, are evaluating and using the NanoKnife to help cancer patients with few other treatment options, such as patients with stubborn tumors that do not respond to chemotherapy or radiation and that lie in locations that are difficult to reach with surgery.

The NanoKnife, made by Angiodynamics Inc., has several thin needles wired to a console that controls the flow of electricity through the needles. Doctors first locate and measure a patient’s tumor using imaging such as computed tomography scanning and real-time ultrasound. While the patient is asleep under anesthesia, physicians next position the NanoKnife probes and insert them through the skin and into the affected organ surrounding the tumor. Quick electric pulses zip through the wires and jump from probe to probe — jolting the tumor. The electricity pierces the cancerous cells, killing them through a process known as irreversible electroporation.

It can take as little as 30 seconds to deliver the electricity, and the cells begin to die almost immediately. Their death signals the patient’s immune system to enter the treated area to clean up the dead and dying cells.

“Unlike similar procedures that use extreme heat or cold to kill tumors, or even surgery, the NanoKnife preserves enough of the local infrastructure and architecture for healthy cells to grow back and rebuild the space where the tumor no longer exists,” John Park said. “This is crucial in treating areas close to vital blood vessels, nerves and other sensitive structures.”

The procedure also causes far less pain than the standard procedures. “Patients want to go home as soon as they wake up,” he said. “Most tell us there’s absolutely no postsurgical pain, which is quite remarkable.”

Park noted that clinical researchers are testing how well it works for specific cancers, so the NanoKnife currently is used only for patients with no other options or as part of a clinical trial.

“So far it’s been used most commonly for tumors in the liver, pancreas, prostate, lungs and other soft-tissue cancers,” he said.

The NanoKnife means important new research opportunities for him and his brother, as well.

“Standard thermal-based procedures destroy cell proteins that can boost immune response, but we still notice some immune response to the destroyed tumors,” John Park said. “The NanoKnife, on the other hand, kills cells without compromising the cell’s proteins, so we think the procedure might play a role in ramping up immune response.”

He and Jinha Park are talking with City of Hope colleagues to explore possible collaborative projects. They hope to begin studies this year.