Abstract
RATIONALE: Adenoid cystic carcinoma is a rare malignant tumor of the salivary glands, with few reports of metastasis to the liver in the literature. We present a case where an isolated hepatic lesion of adenoid cystic carcinoma was identified using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). PATIENT CONCERNS: A 76-year-old male experienced abdominal pain and underwent an enhanced CT scan and magnetic resonance imaging, which revealed a liver mass. Subsequent 18F-FDG PET/CT identified hypermetabolic lesions in both the left and right lobes of the liver, suggesting malignancy, with no other abnormalities detected. DIAGNOSES: A liver biopsy confirmed the diagnosis of adenoid cystic carcinoma. INTERVENTIONS: No intervention. OUTCOMES: Following confirmation of the diagnosis, the patient chose to discontinue treatment and was discharged. LESSONS: Hepatic metastasis from adenoid cystic carcinoma may be detected before the identification of the primary lesion. 18F-FDG PET/CT plays a critical role in differentiating benign from malignant liver tumors, selecting potential biopsy sites, and assessing the extent of metastatic disease.