Hepatic artery embolotherapy of hepatic metastases from carcinoid tumors: value of using a mixture of cyanoacrylate and ethiodized oil.

OBJECTIVE

Transcatheter embolization of the hepatic arterial supply is a well-known palliative treatment of tumor deposits in the liver. We performed a prospective study to evaluate the use of a mixture of N-butyl-2-cyanoacrylate and ethiodized oil with which a permanent vascular occlusion can be obtained, as an embolizing agent for transcatheter hepatic artery embolization for treatment of carcinoid hepatic metastases.

SUBJECTS AND METHODS

Six patients had clinical symptoms from hormonal release by carcinoid hepatic metastases as well as elevated levels of 5-hydroxyindole acetic acid (5-HIAA) in the urine. Unilobar sequential transcatheter embolization of both the hepatic artery and the segmental hepatic arteries of both lobes of the liver was performed with a mixture of N-butyl-2-cyanoacrylate and ethiodized oil. CT and CT arterial portography (CTAP) were done to assess hepatic metastases and were used to monitor follow-up. Each patient had three CTAP studies; the third CTAP, performed 3 months after complete arterial devascularization, was compared with the first CTAP to evaluate tumor size. CT studies were performed routinely every 3 months thereafter and were compared with the initial CT scan to evaluate further tumor regression or progression. Tumor decrease and biochemical and symptomatic response rates were defined according to World Health Organization criteria. All complications and side effects of the treatment were documented.

RESULTS

All patients showed complete symptomatic relief after embolization. The previously elevated levels of 5-HIAA in the urine returned to normal in three patients and in the other three patients were reduced by a mean of 89% of preembolization values. A decrease in tumor size by more than 50% was demonstrable in one patient; in five patients, hepatic lesions decreased in size by 25-50%. No new sites of metastatic liver disease were demonstrable in any patient during follow-up. No deaths or serious complications were directly attributable to the embolization procedure. All patients are alive after 12, 17, 18, 19, 19, and 19 months (mean, 17.3 months), respectively, with permanent relief of symptoms so far.

CONCLUSION

Transcatheter embolization of both the hepatic artery and the segmental hepatic arteries with a mixture of N-butyl-2-cyanoacrylate and ethiodized oil provided excellent palliation in patients with carcinoid hepatic metastases. Complete and long-lasting relief of symptoms, a significant decrease or normalization of levels of 5-HIAA in the urine, and a reduction of metastatic tumor in the liver seem most likely to be the effect of sustained ischemia obtained with this permanent embolizing agent.