Effect of prior cancer on survival of hepatocellular carcinoma: implications for clinical trial eligibility criteria

Patients with cancer history are usually excluded from hepatocellular carcinoma (HCC) clinical trials. However, whether previous malignancy affects the oncological outcomes of HCC patients has not been fully assessed. This study aimed to evaluate whether prior cancer compromised the survival of HCC patients. Patients with HCC were extracted from the Surveillance, Epidemiology, and End Results database between 2004 and 2015, and then they were classified into groups with and without prior cancer. The Kaplan-Meier and multivariate Cox regression analysis were adopted to evaluate whether prior cancer impacted clinical outcomes after propensity score matching (PSM) adjusting baseline differences. Validation was performed in the cohort from our institution. We identified 2642 HCC patients with prior cancer. After PSM, the median overall survival (OS) time were 14.5 and 12.0 months respectively for groups with and without prior cancer. Prior cancer did not compromise prognosis in patients with HCC (p = 0.49). The same tendency was found in subgroups stratified by tumor stages and cancer interval period: OS was similar between groups with and without prior cancer (both p values> 0.1). In the multivariate Cox regression model, prior cancer did not adversely impact patients' survival (HR: 1.024; 95% CI: 0.961-1.092). In the validation cohort from our institution, prior cancer had no significant association with worse outcomes (p = 0.48). For HCC patients, prior cancer did not compromise their survival, regardless of tumor stage and cancer interval period. Exclusion criteria for HCC clinical trials could be reconsidered.