Evaluation of Transarterial Radioembolization with Iodine-131 Lipiodol for Hepatic Metastases

Purpose: To analyze the response and survival benefits of transarterial radioembolization (TARE) with Iodine-131 Lipiodol (¹³¹I-Lipiodol) for hepatic metastases.

Materials and Methods: This is a prospective study of 600 patients between May 2015 and December 2020 with pathologically proven hepatic metastases referred for palliative therapy with TARE. At baseline (the day of the first session of intraarterial treatment), standard laboratory data, including tumor marker levels; imaging characteristics of the liver and hepatic lesions from cross-sectional imaging (computed tomography or magnetic resonance imaging); and prior treatment history were recorded. After the procedure, the patients were reviewed after 1 month with a follow-up positron emission tomography and tumor marker levels to evaluate response of treatment.

Results: At the end of follow-up period, 84 patients had died. The mean overall survival period after TARE was 34.415 ± 3.0 months. The mean durations of survival were found to be 38.88 ± 5 months in neuroendocrine tumors (NETs), 35.118 ± 3.95 months in gastrointestinal (GI) malignancies, 27.21 ± 8.3 months in pancreaticobiliary malignancies, and 20.685 ± 5.2 months in other malignancies (P = 0.17). The overall survival rate after 45 months was 70%. Forty-five-month survival periods were 76% in NET, 75% in GI malignancies, 57% in pancreaticobiliary malignancies, and 50% in other malignancies. Response evaluation could not be done in 27 patients because they did not undergo follow-up imaging. In the rest of the 489 patients, 266 patients showed a partial response, 155 patients showed stable disease, and 66 patients showed progressive disease. In 222 patients with NET, 169 patients showed partial response, 30 patients showed stable disease, and 23 patients showed progressive diseases. In 133 patients with GI malignancies, 95 patients showed partial response, 25 patients showed stable disease, and 13 patients showed progressive disease. In 88 patients with pancreaticobiliary malignancies, 61 patients showed partial response, 18 patients showed stable disease, and 9 patients showed progressive disease. All 46 patients with other malignancies showed stable disease.

Conclusions: TARE with ¹³¹I-Lipiodol is highly effective in patients with hepatic metastases, especially in those with poor responses to other treatments, and has shown significant survival benefit and better quality of life. TARE with ¹³¹I-Lipiodol has an added advantage of being cost effective compared with TARE with 90-Yttrium–embedded microspheres in developing countries such as India.