Late Parotid Recurrence of Hepatocellular Carcinoma Following Liver Transplantation: A Case Report

Metastatic recurrence to the parotid gland following liver transplantation has not been previously reported. We describe a case of a 63-year-old man with hepatocellular carcinoma secondary to alcoholic cirrhosis who was treated with transarterial chemoembolization and microwave ablation, achieving radiographic downstaging within the Milan criteria. He underwent liver transplantation with an exception Model for End-Stage Liver Disease score of 27. Explant pathology revealed moderately differentiated multifocal tumors with negative margins. He remained recurrence-free for 31 months under protocol-based surveillance. He then developed a facial mass; two core needle biopsies were nondiagnostic. Surgical resection confirmed moderately to poorly differentiated metastatic hepatocellular carcinoma involving the parotid gland and zygomatic arch. Tumor markers rose only modestly at the time of recurrence. Despite targeted therapy and radiation, the disease progressed, culminating in widespread metastasis and death 13 months after recurrence. Immunotherapy was deferred due to the risk of graft rejection, and conversion to an mTOR-based regimen was not recommended. This case highlights the challenges in long-term posttransplant surveillance, diagnostic limitations of core biopsy in atypical lesions, and systemic treatment constraints in immunosuppressed patients.