Salivary gland adenoid cystic carcinoma presenting as a large metastatic hepatic mass: a case report.

Background: Salivary gland tumors are rare, representing 6-8% of head and neck tumors. Adenoid cystic carcinoma represents approximately 10% of salivary gland tumors. The preferential sites of metastases are the lung and bone, followed by the brain and liver. Liver metastasis as the initial clinical manifestation of parotid gland adenoid cystic carcinoma is very rare.

Methods: We report the case of a 29-year-old African American male patient with a metastatic salivary gland tumor who presented initially with a large hepatic mass. He complained of right upper quadrant pain and early satiety. Abdominal computed tomography revealed hepatomegaly with a large mass centered in the left lobe measuring 14 cm. A computed tomography scan revealed innumerable bilateral pulmonary nodules measuring up to 8 mm, favoring metastases. Initial histopathological examination of the liver biopsy specimens revealed a well-differentiated carcinoma characterized by a distinctive myxoid stroma, consistent with metastatic adenoid cystic carcinoma. The patient underwent transcatheter arterial chemoembolization and was discharged with a hematology-oncology follow-up. A presumptive diagnosis of stage IV adenoid cystic carcinoma with lung and liver metastases was made. The patient was given cisplatin and vinorelbine.

Conclusions: Metastatic parotid gland adenoid cystic carcinoma with initial clinical manifestation as a liver mass is very rare and was pathologically confirmed in this patient by its histological appearance. This case emphasizes the need for clinicians to consider salivary gland tumors in the differential diagnosis of unexplained hepatic lesions.