Patients with inoperable liver cancer treated with targeted chemotherapy administered by an interventional radiologist live longer and experience a better quality of life, according to a new study.

Eleni Liapi, M.D.
The Johns Hopkins School of Medicine

The study examined the outcomes for several hundred patients with hepatocellular carcinoma (HCC) who were treated with transcatheter arterial chemoembolization (TACE). Results were presented at RSNA 2008 by Eleni Liapi, M.D., a post-doctoral research fellow in the Division of Interventional Radiology at The Johns Hopkins University School of Medicine in Baltimore.

HCC is the fifth leading cause of cancer worldwide and its incidence is increasing. There are 19,000 cases each year in the United States and 350,000 to one million cases a year worldwide. HCC usually progresses slowly and silently, and there are usually no tumor-related symptoms at an early stage.

The most common curative treatment options for HCC include surgical resection, liver transplantation and chemical or thermal ablative therapies. "Fewer than 20 percent of the patients we see can be treated surgically," Dr. Liapi said.

The other 80 percent of patients with HCC have the choice of receiving systemic chemotherapy or chemoembolization as palliative options.

The study conducted by Dr. Liapi and colleagues included the largest series of patients with unresectable HCC treated with TACE in the U.S. TACE was performed on 347 patients in 979 sessions. All patients underwent MR and/or CT imaging at baseline and at four to six weeks after each session.

The Johns Hopkins protocol includes the selective injection of three chemotherapeutic agents—cisplatin, doxorubicin and mitomycin C—mixed with ethiodized oil. Those agents are followed by embolic agents to prevent chemotherapy washout to other areas of the body.

Patients were clinically, biochemically and radiologically evaluated before each session. Disease status was evaluated before and at the end of the treatment period with the Child-Pugh class system and tumor size measurements were evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST). The researchers used Eastern Cooperative Oncology Group (ECOG) scoring to evaluate the patients' performance status.

"First of all, we saw that chemoembolization is an effective treatment for unresectable hepatocellular carcinoma, with minimal systemic toxicity," said Dr. Liapi. "We don't see the same side effects that we see with systemic chemotherapy."

The targeted therapy allows for a higher dose of chemotherapy to be used because less of the drug is able to circulate to the healthy cells of the body.

The median survival time for the entire group of patients was 20.25 months. "This is actually very good when we compare it to the survival of patients who receive the best supportive care or systemic chemotherapy," Dr. Liapi said. "If these patients do not receive any treatment, they die within six months."

Patients' performance status over time did not change. "They remained functional throughout the course of the disease," said Dr. Liapi. "They could keep on with their daily activities and did not experience any significant side effects. Their quality of life did not deteriorate because of TACE."

TACE did not further deplete the patients' hepatic reserve. "People with unresectable hepatocellular carcinoma also often have underlying liver disease," Dr. Liapi said. "It is important to preserve their liver function and this is another advantage of local delivery."

Two other studies presented at RSNA 2008 indicate that percutaneous cryoablation results in minimal loss of renal function and that intraprocedural monitoring with CT and MR

Adam Weisbrod, M.D.
Mayo Clinic

Kemal Tuncali, M.D.
Harvard University Medical School

allows tumors to be ablated completely in one session.

Another study presented, however, called for caution in CT-guided procedures, indicating that patient radiation dose during one procedure is approximately equivalent to eight standard abdominal CT scans.

Radiology resident Adam Weisbrod, M.D., presented a retrospective review of 175 patients, each with a single kidney, who underwent cryoablation at Mayo Clinic in Rochester, Minn., from March 2003 to November 2008.

In the study, 38 tumors with a mean size of 3 cm were treated. Researchers compared creatinine levels pre-ablation, immediately post-ablation, three to six months post-ablation and, finally, the patient's most recent creatinine level to assess whether there was significant loss of kidney function.

"As expected, there is an initial decrease in their renal function, with eventual establishment of a new baseline," said Dr. Weisbrod. "We found their new baseline reflected a minimal decrease in renal function with a median increase in creatinine of 0.1 milligrams per deciliter. That number is very comparable to surgical literature for partial nephrectomy in these patients.

"Notably, none of the patients in our study required dialysis," Dr. Weisbrod said.

Paul R. Morrison, M.S.
Brigham and Women's Hospital

A second study presented by Kemal Tuncali, M.D., assistant professor of radiology at Harvard University Medical School, examined 180 renal masses treated with CT and MR-guided cryoablation. Multiple cryoprobes were placed and tumors were ablated using iceball monitoring. Of 149 tumors followed for three months or more, 142 (95 percent) were successfully ablated. Tumors successfully treated required only one ablation procedure.

"This is a midterm follow-up and these results show very promising, successful results comparable to surgical methods in treating these tumors," said Dr. Tuncali.

Cryoablation is a reasonable alternative for patients with a single kidney and renal insufficiency, with advanced age or other risks for surgery, and those who prefer a minimally invasive treatment method supported by their urologist instead of surgery, said Dr. Tuncali.

Nevertheless, the effective dose of radiation given to patients during CT-guided renal cryroablation should be considered carefully, according to a report by Paul R. Morrison, M.S., a medical physicist in radiology at Brigham and Women's Hospital in Boston.

He reviewed 50 cases and found, on average, 71 millisieverts (mSv) were delivered per procedure—an equivalent of eight standard abdominal spiral CT scans. "The effective dose we have estimated is substantial," he said. However, he added, CT provides value by both targeting the lesion and monitoring the freezing.

Abstracts for these studies can be found at RSNA2008.RSNA.org/event_display.cfm?em_id=7002546.

Note: These articles were adapted from stories that appeared in the RSNA 2008 Daily Bulletin. Daily newspapers from the annual meeting are available online at RSNA.org/bulletin.

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