May 8, 2012 | by City of Hope Staff
City of Hope radiologists are using the NanoKnife, a medical tool that destroys tissue using electricity, to zap stubborn tumors that do not respond to chemotherapy or radiation and that lie in locations that are difficult to reach with traditional surgery.
John Park, M.D., chief of the Division of Interventional Radiology in City of Hope’s Department of Diagnostic Radiology, and several of his colleagues have started using the new unit. The NanoKnife consists of several probes wired to an electric source. While a patient sleeps under anesthesia, doctors carefully insert the probes into the patient’s body so they surround the tumor. The physicians know just where to place the probes because they use CT scans, real-time ultrasound or other imaging methods to see the tumor’s location and size.
Once the probes rest in place around the tumor, the physicians send pulses of electricity into the NanoKnife. Electrons jump from probe to probe, jolting the tumor and punching holes in the cancerous cells in their path. The electricity flows for as little as 30 seconds. When it’s over, the tumor cells are damaged beyond repair. The body’s immune system then steps in to clean up dead cells.
The NanoKnife also affects nearby healthy tissues, but unlike surgery and procedures that use extreme heat or cold to kill tumor cells, the NanoKnife leaves the basic structures necessary for the body to rebuild the area with healthy cells. Best of all, patients report little or no pain following the procedure. “Patients want to go home as soon as they wake up,” Park said.
According to Park, the NanoKnife is most commonly used to treat tumors in soft tissues, such as in lung, prostate, pancreatic and liver cancers. Because clinical researchers are testing how well the NanoKnife works for specific cancers, the device currently is used only for patients with no other options or as part of a clinical trial.