PET Response Criteria for Solid Tumors Predict Survival at Three Months After Intra-Arterial Resin-Based 90Yttrium Radioembolization Therapy for Unresectable Intrahepatic Cholangiocarcinoma

PURPOSE: PET Response Criteria for Solid Tumors (PERCIST) were assessed and correlated with survival analysis after resin-based 90Yttrium (90Y) radioembolization therapy for intrahepatic cholangiocarcinoma (ICC). PATIENTS AND METHODS: Target and overall PERCIST and Response Criteria for Solid Tumors (RECIST) treatment responses were assessed in consecutive patients treated with Y radioembolization for ICC refractory to standard chemotherapy. Significant measurable tumor was defined as 1 cm or greater in diameter and SUVpeak of 2.5 or greater in targeted and nontargeted lesions. The PERCIST defines complete response as resolution of 18F-FDG uptake within measurable lesions, and partial response as 30% reduction in 18F-FDG peak standardized uptake value in measurable lesions. Objective response included partial response and complete response. Survival analysis by Kaplan-Meier and log-rank proportional models was performed using SPSS software version 20.0 (IBM, Armonk, NY), and significance was set at P < 0.05. RESULTS: Median overall survival (OS) of 9 consecutive patients (56% women; mean age, 58 years) from 90Y therapy was 21.7 months. At 3 months, PERCIST objective response rate of target lesions was 77.7%, and target objective response on PERCIST correlated significantly to prolonged OS (P = 0.022). Overall objective PERCIST response at 3 months had significant correlation with OS (P = 0.011). Probability of death was significantly higher in overall nonresponders by PERCIST (hazard ratio, 12.3). No objective response was seen with RECIST. CONCLUSIONS: In patients with unresectable ICC refractory to standard chemotherapy, PERCIST at 3 months for assessment of imaging response after 90Y radioembolization therapy predict OS.