Electricity Used To Kill Liver Cancer

45-Second Electrical Pulses Destroy Tumor Without Large Incisions

This year, 15,000 men and 6,000 thousand women will be told they have liver cancer, according to the National Cancer Institute. For patients whose cancer hasn't spread, a liver transplant offers the option of a cure, but the surgery comes with a risk of rejection and a lifetime of medications. One new procedure offers hope of a cure without a transplant.

The Gomezes have had 47 years of marriage to make memories -- some sweet and some they'd like to forget.

"I had this lesion that was 2.5 centimeters," Maria Gomez said.

Gomez was diagnosed with liver cancer three years ago. Major surgery was her only option.

"I was down for about two weeks," Gomez said.

Last year, the cancer came back. Gomez chose to delay a liver transplant with a new treatment called IRE, or irreversible electroporation. Guided by CT scans, interventional radiologists used thin needles to insert probes around Gomez's tumor.

"Once we have identified the appropriate placement of the probes, we then connect them to a generator, and it kills the tumors by using very high-voltage electricity," said Dr. Govindarajan Narayanan, chief of Vascular Interventional Radiology at the University of Miami.

The 45-second electrical pulses create multiple holes in the membrane of the cancer cells, destroying the tumor. The body naturally removes the cell structure that's left behind. Unlike traditional ablation, the approach allows radiologists to reach tumors close to blood vessels and leaves no scar tissue behind. No large incisions are required.

Narayanan said ideal candidates for IRE have liver tumors smaller than five centimeters, or they aren't eligible for a transplant. Patients with tumors on multiple organs or who have a pacemaker aren't candidates for the procedure. Doctors plan to use the treatment for cancers of the lungs and kidneys and have successfully performed it on the first case of pancreatic cancer.

BACKGROUND: According to the National Cancer Institute, more than 22,000 cases of liver cancer were diagnosed last year, and the disease caused more than 18,000 deaths. Although it's common for cancer to spread to the liver from other organs such as the colon, lungs and breasts, the disease is not liver cancer unless it begins in the liver.

Currently, the only hope of a liver cancer cure is surgery, according to the American Cancer Society. Surgeons perform operations to remove the tumor or do a liver transplant. Often, the cancer is large, in many different parts of the liver, or has spread outside the liver, making treatment difficult.

While a liver transplant is an option for people with small liver cancers, not many livers are available for transplant to patients with cancer because they are most often used for more curable diseases, the American Cancer Society said. Because of this, doctors often suggest a surgery to remove as much cancer as possible and then a transplant if the cancer returns. Even if a patient receives a liver transplant to cure cancer, they must rely on immunosuppressive drugs -- which carry side effects of serious infections and other health problems -- throughout their lifetime to retain the organ.

ELECTROCUTING TUMORS: Some liver cancer patients are candidates for a treatment called ablation. Ablation involves destroying a tumor without removing it, but is most often used for patients with a few small tumors that cannot be removed for surgery. Ablation techniques aren't designed to cure liver cancer, but to help patients live longer.

A new type of ablation is based on a technique called electrophoresis, which involves using electrical energy to alter cell membranes and allow chemotherapy drugs to enter more freely. The technique used in the past to deliver chemotherapy -- called reversible electrophoresis -- allowed the cell membranes to close up again. In a new treatment called irreversible electrophoresis, interventional radiologists use a higher voltage to cause permanent damage to cancer cells. The radiologists place probes through 2 to 3 millimeter incisions around a cancerous tumor and connect them to a generator. The generator is turned on and fires an electrical pulse that travels to the tumor cells.

"The probes generate very high-voltage electricity, and what that does is it creates multiple holes in the cell membrane and kills the cell organelles, but leaves the cell membrane intact," said Dr. Govindarajan Narayanan, chief of Vascular Interventional Radiology at the University of Miami. "The body removes the dead cell membranes like it’s a part of a dead cell in the body, so when the healing process takes place, it almost looks like the tumor was not there whereas with radio-frequency ablation and cryoablation, you have a scar."

The procedure is guided by CT scans or ultrasound and has been used to treat lung and pancreatic cancer. Doctors also plan to use irreversible electrophoresis in the treatment of kidney cancer. Narayanan said if the tumor being treated is close to a lung, there is a risk of pneumothorax, or partial collapse of the lung.