Unresectable ectopic hepatocellular carcinoma in the left sub-diaphragmatic area and retroperitoneum treated with TACE: case report and literature review

Ectopic hepatocellular carcinoma (EHCC) demonstrates morphological and immunohistochemical features identical to conventional intrahepatic hepatocellular carcinoma (HCC), originating from ectopic liver tissue (EL), which is defined as a hepatic organ or tissue not connected to the mother liver. EHCC is a rare disease and difficult to diagnose preoperatively. Therefore, its epidemiology, treatment, and prognosis are not fully elucidated. Herein, we present a case report of a 52-year-old male diagnosed with unresectable EHCC who underwent transarterial chemoembolization (TACE) and succumbed to the disease 13 months after treatment, accompanied by a literature review summarizing the epidemiology while analyzing therapeutic strategies and prognostic outcomes in EHCC through synthesis of published case evidence.