Clinical significance of radiotherapy before and/or during nivolumab treatment in hepatocellular carcinoma

BACKGROUND: This study aimed to investigate the clinical significance of previous and/or concurrent application of radiotherapy (RT) in the course of nivolumab treatment for advanced hepatocellular carcinoma (HCC). METHODS: Patients with advanced HCC who received nivolumab treatment between March 2017 and May 2018. were included. Nivolumab treatment was indicated in patients who did not respond to conventional therapy including locoregional therapy and/or sorafenib. RT was performed when necessary for curative/palliative purpose. RESULTS: Among the 76 HCC patients who received nivolumab, 54 (71.1%) had received RT for HCC before and/or during the treatment. The period from initial HCC diagnosis to nivolumab treatment was significantly longer (P = .007) and the rate of undergoing transarterial chemoembolization (TACE; P = .006) and sorafenib treatment (P = .007) was significantly higher in patients who received previous/concurrent RT than in those who did not. Nivolumab‐related toxicities were generally tolerable regardless of the history of RT. During the follow‐up, 39 (51.3%) patients died and 54 (71.1%) patients experienced disease progression according to the RECIST v1.1. Patients who had received previous/concurrent RT had a significantly longer progression‐free survival (PFS; P = .008) and overall survival (OS; P = .007) than those who did not receive RT; however, this trend was not observed in patients with a history of radiofrequency ablation or TACE (all P > .05). CONCLUSION: Previous and/or concurrent application of RT in the course of nivolumab treatment was related with longer PFS and OS in advanced HCC patients. Nonetheless, further clinical studies are warranted to confirm our findings.