Yttrium-90 radioembolization as salvage therapy for liver metastases from colorectal cancer

Purpose: To report safety and survival outcomes of Yttrium-90 (Y-90) radioembolization when used as salvage therapy for chemotherapy-resistant liver metastases from colorectal cancer. Methods: In this IRB-approved retrospective study, 45 patients with hepatic metastases from colorectal cancer underwent Y-90 radioembolization after failure of systemic chemotherapy. Toxicities were assessed as per NCI-CTCAE and response based on RECIST and PET. Kaplan-Meier survival analysis was performed to calculate median survival, prognostic factors on univariate analysis, and Cox regression analysis for independent predictors of survival. Results: Y-90 radioembolization was technically successful in all (100%). Twenty-three patients (51%) had no toxicities, whereas 6 patients (13%) had grade 3 toxicities, and no patients had grade 4 toxicity. Two patients died within 30 days of treatment from renal failure unrelated to the procedure. Per RECIST, 1 patient (2%) had partial response, 34 (71%) had stable disease, and 6 (13%) had progressive disease. PET response was seen in 46% of patients with 2 patients (4%) demonstrating complete and 22 (42%) demonstrating partial metabolic response. The median survival was 186 days (95% CI, 149-277 d). Response on PET was the only independent predictor of superior overall survival. Patients who had response on PET following Y-90 therapy had a median overall survival of 317 days (10.6 mo) (95% CI, 193-564 d), whereas patients with no response on PET had a median overall survival of 163 days (5.4 mo) (95% CI, 64-283 d). Conclusions: Y-90 radioembolization as a salvage therapy for chemotherapy-resistant hepatic metastases from colon cancer was safe and resulted in disease stability. Response on PET was an independent predictor of superior overall survival.