title: Hepatocellular carcinoma metastatic to the gingiva as a first manifestation of hepatocellular carcinoma.
abstract: A 55-year-old man consulted to our hospital complaining of a gingival tumor. Oral examination showed granulation tissue-like polypoid tumors (2 × 2 × 1 cm) in the left upper gingiva. A clinical diagnosis of granulation tissue was made, and an incisional biopsy was performed. It showed carcinoma cells in the submucosa. They were arranged in compact and sinusoidal patterns. A few bile plugs and one Mallory-like body were recognized by meticulous examination. An immunohistochemical study showed that the tumor cells were positive for hepatocyte paraffin-1 (HepPar-1), cytokeratins (AE1/3 and CAM6.2), and p53 protein. The carcinoma cells were negative for vimentin, prostate specific antigen, CD10, and α-fetoprotein. The Ki-67 labeling was 49%. A histological diagnosis of hepatocellular carcinoma (HCC) metastatic to the gingiva was made. Then, the patient was referred to hepatology unit. A blood laboratory test showed elevated elevated liver enzymes, and positive antibody to hepatitis C virus. Liver cirrhosis was also present. Imaging modalities including US, CT, and MRI revealed multiple hepatic tumors. Metastases to other sides were not recognized. The patient was diagnosed as cirrhosis and HCC with an extrahepatic metastasis to the gingiva. The patient was now treated by chemotherapy. The present case shows that HCC can manifest as small gingival tumors, and meticulous HE examination and immunoreactive HepPar-1 are useful in the diagnosis of HCC in extrahepatic metastatic sites.
authors.affiliation: Department of Pathology, Shizuoka City Shimizu Hospital, Miyakami 1231, Shimizu-Ku, Shizuoka, 424-8636 Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Terada