Association between pretreatment retention rate of indocyanine green 15 min after administration and life prognosis in patients with HCC treated by proton beam therapy.

Abstract

The Child-Pugh score is often used to judge the outcome of radiotherapy for hepatocellular carcinoma (HCC). The retention rate of indocyanine green 15 min after administration (ICG R15) can also be used to predict prognosis after liver resection. We evaluated the utility of ICG R15 for prediction of outcomes after proton beam therapy (PBT) for HCC. A retrospective evaluation was performed in 250 patients who received PBT between 2002 and 2007. The patients (178 males and 72 females) had a median age of 71 years (range: 43-88). Child-Pugh categories were A (score 5-6), B (7-9), and C (10-15) in 197, 51, and 2 patients, respectively. ICG scores were 0-<10, 10-<20, 20-<30, 30-<40 and ⩾40 in 27, 99, 59, 28 and 37 patients, respectively; including 26, 92, 45, 16 and 18 Child-Pugh A patients and 1, 8, 14, 11, and 17 Child-Pugh B patients, respectively. Survival times from the start of PBT were compared between Child-Pugh A and B patients, and among each ICG group. The median survival times were 61 months (95% CI: 50-72 months) in all patients, and 64 and 20 months in Child-Pugh A and B patients, respectively (p=0.001), The 3-year survival rates were 72%, 72%, 75%, 63%, and 26% in patients with ICG scores of 0-<10, 10-<20, 20-<30, 30-<40, and ⩾40 (p=0.001); 70%, 75%, 77%, 65%, and 38% in these respective groups in Child-Pugh A patients (p=0.02); and 100%, 57%, 67%, 36%, and 14% in Child-Pugh B patients (p=0.173, not significant). Multivariate analysis showed that low ICG R15 and the absence of portal vein tumor thrombus were associated with good survival. Pretreatment ICG R15 is a useful prognostic factor for prediction of outcome of PBT in HCC patients, especially in those with Child-Pugh A liver function.