Abstract:

Secretory carcinoma of the salivary gland is a rare low-grade malignant salivary gland tumor characterized by the distinctive ETV6-NTRK3 fusion gene. It was formally included in the 2017 WHO Classification of Head and Neck Tumors. This tumor most commonly arises in the parotid gland, followed by the submandibular gland and minor salivary glands of the oral cavity, with primary occurrence in the tongue being extremely rare. Only one case of tongue involvement has been reported in the literature, and that was located at the base of the tongue; no cases originating in the anterior tongue have been documented to date.This report describes a case of secretory carcinoma arising in the anterior tongue. The patient was a middle-aged male who presented with a mass in the anterior tongue. The tumor was completely resected surgically. Postoperative hematoxylin and eosin (HE) staining revealed a tumor exhibiting multiple growth patterns, including tubular, papillary, cystic, and solid architectures, accompanied by eosinophilic secretory material and focal necrosis. Combined with characteristic immunohistochemical findings, the final diagnosis was secretory carcinoma of the salivary gland. The rare site of occurrence in this case increased the difficulty of preoperative diagnosis, highlighting the need for clinicians to consider the possibility of secretory carcinoma when encountering solid masses in the tongue. This article, combined with a literature review, summarizes the clinicopathological features, molecular mechanisms, and differential diagnosis of this tumor type, with the aim of enhancing awareness of this entity and increasing vigilance regarding its occurrence at unusual sites.

Key words: secretory carcinoma of the salivary gland, malignant salivary gland tumor of the tongue, ETV6, immunohistochemistry