Interventional options open palliative avenues

The options available for treating focal liver disease are expanding. For patients with advanced disease who are seeking temporary relief rather than restoration of full health, or those who want a downstaging solution to make them eligible for surgery, interventional radiologists have plenty to offer.

"There has been a paradigm shift in the treatment of the liver. In the past few years, there has been a tremendous interest in palliation," said Dr. Dushyant Sahani, an assistant professor of radiology at Harvard University and director of CT at Massachusetts General Hospital in Boston, Massachusetts.

Image-guided ablation has recently emerged as a robust technique for treating patients with relatively small liver lesions that cannot be removed safely by surgery.

Most practitioners favor the use of thermal ablation using radiofrequency (RF) energy. The localized heat treatment, which induces coagulative necrosis in tumor tissue, can also be performed using a laser as the energy source (laser-induced interstitial thermal therapy).

A small but significant proportion of ablative procedures rely on alcohol rather than heat to destroy liver cancers. Ethanol is injected through a thin needle to the target site where it draws water out of tumor cells, denaturing cellular proteins. It may take up to five or six sessions to completely destroy a malignant lesion. The procedure is contraindicated for patients with liver failure, who would be unable to tolerate the alcohol injections.

FIRST-LINE TOOL

Ablation is often used as a first-line tool in patients with primary liver cancer who cannot undergo surgery because underlying cirrhosis has left them with impaired liver function, said Prof. Riccardo Lencioni, a professor of radiology in the oncology department at the University of Pisa in Italy. This option is available to patients with up to three liver lesions that are no more than 3 to 4 cm in diameter.

Similar criteria are used to select candidates for RF ablation at the Kinki University Medical School in Osaka, Japan. Patients with a solitary liver lesion that is greater than 3 cm in diameter will be offered surgery instead.