Safety and efficacy of resin 90Y-microspheres in 548 patients with colorectal liver metastases progressing on systemic chemotherapy.

Abstract

264 Background: 90Y-microspheres (radioembolization) are administered via the hepatic artery following failure of one or more lines of fluoropyrimidine-based systemic chemotherapy, with or without biologic agents in colorectal carcinoma metastatic (mCRC) to the liver. Methods: A retrospective review of consecutively treated patients with mCRC from July 2002 to December 2011 at 11 U.S. institutions was conducted. Data on background characteristics, prior chemotherapy, surgery/ablation, radiotherapy, vascular procedures, 90Y treatment (SIR-Spheres; Sirtex Medical), subsequent adverse events (grade 3+) and survival were documented. Median follow-up was 8.5 mo. (IQR 4.3–15.6). Trends in the occurrence of adverse events for patients receiving 1, 2, or 3+ lines of systemic chemotherapy were evaluated by Fisher’s Exact. Kaplan Meier estimates compared the overall survival of patients across lines of chemotherapy. Results: A total of 548 patients were included; majority were male (61%), Caucasian (66%), mean age 61 years; received median of 2 (range 1–6) lines of chemotherapy prior to 90Y therapy. Median tumor/liver ratio at 90Y therapy was 15% (IQR 23%). Median 90Y activity administered was 1.18 GBq (IQR 0.48). Hospital stay duration was <24 hours for most cases (97.8%). The most common adverse events (grade 3+) following 90Y therapy included: abdominal pain 6.6% (n=36), GI ulceration 1.8% (10), nausea 1.5% (8), vomiting 1.6% (9), fatigue 6.0% (33), ascites 3.5% (19), hyperbilirubinemia 5.7% (31) and anorexia 1.1% (6). A comparison of 1, 2 and 3+ lines of chemotherapy versus grade 3+ adverse events to 3 months post-90Y therapy revealed no significant difference (p>0.05). Corresponding median survivals (95% CI) were 13.0 (10.5–14.6), 9.0 (7.8–11.0) and 8.1 (6.4–9.3) months, respectively (p<0.0001). Conclusions: 90Y microsphere therapy appears to have a favorable risk/benefit ratio in patients with mCRC who have failed prior systemic chemotherapy. These data show a clinically relevant survival benefit for 90Y therapy in patients not responding to chemotherapy, including those heavily pre-treated (3+ lines).