Dima Dandachi, Manal Hassan, Ahmed Kaseb, Georgios Angelidakis, Harrys A Torres

Chronic hepatitis C virus (HCV) infection is one of the leading causes of hepatocellular carcinoma (HCC) worldwide. Antiviral therapy in patients with HCV infection reduces the risk of primary HCC development by 71%-75%. HCV-infected patients with different primary cancers are also at risk for HCC development as a second primary malignancy (HCC-SPM). Limited information is available on the occurrence and characteristics of HCC-SPM. Herein, we determine the prevalence and clinical features of HCV-associated HCC-SPM when compared to primary HCC. Patients with HCV-associated HCC seen at MD Anderson Cancer Center (2011-2017) were enrolled in a prospective observational study. Patients with multiple cancers diagnosed simultaneously or with hepatitis B virus or HIV coinfections were excluded. At enrollment, patients completed a questionnaire on medical history and HCC risk factors. Information on demographics, comorbidities, HCV treatment, tumor characteristics, treatment modalities, and virologic and oncologic outcomes were extracted from the medical records. Among 171 consecutive patients with HCV-associated HCC enrolled, 26 (15%) had HCC-SPM. Most of the underlying primary cancers were solid tumors (85%). In 12 (46%) of these patients, the diagnosis was made incidentally while undergoing surveillance for primary malignancies, and the majority (81%) had their primary cancer in remission. Most patients (72%) with documented HCV viral load had chronic viremia due to lack of diagnosis, lack of treatment, or prior unsuccessful treatment of HCV infection and only 28% had undetectable viral load following successful antiviral therapy. The overall median survival for both groups was 29 months (95% CI: 23-35) without difference between groups (p=0.2). Cancer patients with any malignancies must be screened for HCV as HCC-SPM can develop in 15% of infected patients. Early HCV diagnosis and treatment should be attempted to prevent the development of HCC-SPM, a condition associated with high mortality in cancer survivors.