Metastatic carcinoma with hepatic differentiation: a rare case in the oral cavity

This study reports a case of an 81-year-old male patient with an ulcerative lesion in his mouth. The clinical hypothesis was squamous cell carcinoma. After an incisional biopsy was performed, the anatomopathologic diagnosis was of a malignant neoplasm with ulceration. An immunohistochemical study revealed positivity for hepatocyte (strong and diffuse) and cytoplasmic positivity for TTF1 and cytokeratin (AE/AE3). Differential diagnoses such as melanoma, primary pulmonary site, primary site of the gastrointestinal tract, malignant vascular neoplasms, and primary adrenal site were discarded. These aspects were based on the negative expression of markers (CK7, CK20, CD31, ERG, CD45, Melan-A, CD34, S-100, p63, and CDX2). These findings are consistent with the diagnosis of a moderately differentiated metastatic carcinoma favoring an ulcerated hepatocellular carcinoma. The patient was referred for treatment at a referral service.