Salvage Radioembolization of Liver-dominant Metastases with a Resin-based Microsphere: Initial Outcomes

Purpose: The use of radioembolization of hepatic metastases with yttrium-90 (⁹⁰Y) microspheres is increasing. The present report describes the outcomes in a cohort of patients with metastatic liver tumors treated with a resin-based microsphere agent. Materials and Methods: Thirty patients with colon (n = 13), breast (n = 7), and other primary cancers (n = 10) were treated after the failure of first- and second-line therapy. Overall survival (OS), time to progression (TTP), and time to treatment failure (TTTF) were calculated from the first treatment. Response was measured according to Response Evaluation Criteria In Solid Tumors at interval follow-up imaging. Results: Thirty patients underwent 56 infusions of ⁹⁰Y, and 18 remained alive at the end of the study. Fourteen patients (47%) had a partial response or stable disease. OS (604 vs 251 days), TTP (223 vs 87 days), and TTTF (363 vs 87 days) were all significantly longer for patients who had a partial response or stable disease (P < .05). Median OS, TTP, and TTTF for patients with colorectal carcinoma were 357, 112, and 107 days, respectively, versus 638, 118, and 363 days in patients with other metastatic sources. Median survival was not reached for patients with breast carcinoma, and the TTP and TTTF were each 282 days. One patient (3%) experienced grade 3 toxicity (gastrointestinal ulceration). Conclusions: ⁹⁰Y microsphere therapy produced promising survival rates compared with systemic salvage options, with minimal toxicity.