Submandibular adenoid cystic carcinoma presenting with liver metastasis as the initial symptom: A case report.

Adenoid cystic carcinoma (ACC) is a rare and aggressive malignancy characterized by a high incidence of distant metastasis. However, cases of ACC with liver and lymph node metastases are rarely reported and lack a standardized treatment consensus. The present report describes the case of a submandibular gland ACC with liver metastasis manifesting as the initial symptom. PET/CT revealed masses in the left submandibular gland and the liver. The patient underwent right tri-lobe hepatectomy and resection of the submandibular gland tumor. Histological examination of the tumor revealed a cribriform type with both lymphovascular invasion and perineural invasion. New lymph node metastases were observed 21 months after surgery of the submandibular gland tumor, and no further treatment was administered to date. The patient has survived for 28 months since the diagnosis of liver metastasis and currently exhibits stable vital signs. In conclusion, the present case illustrates a rare, high-risk variant of rapidly progressing submandibular gland ACC, with liver metastasis serving as the initial presenting symptom. A multidisciplinary approach is essential for the effective management of complex metastatic ACC.