Diagnosis and management of malignant sublingual gland tumors: a narrative review

Objective: In this article we review the literature on the malignant sublingual gland tumors from a surgical perspective. Background: Sublingual gland tumors occur with a very low incidence and most are malignant tumors. The extent of treatment, clinical outcomes and prognosis of malignant sublingual gland tumors have not been well defined, due to the rarity of this disease. Methods: A database search using Web of Science (https://webofknowledge.com/) and PubMed (https:// pubmed.ncbi.nlm.nih.gov/) was conducted. The following keywords were used in the search: "sublingual gland tumor", AND "malignancy". Conclusions: Although the sublingual glands are among the major salivary glands, they share common anatomical characteristics with minor salivary gland tumors. Therefore, the tumors from the sublingual gland may have different clinical behaviors from the other major salivary gland tumors. The sublingual glands are small without a true surrounding capsule of the glands; the extra-parenchymal extension is very common in sublingual gland tumors. Furthermore, the sublingual glands are located in close proximity to the lingual nerve, the submandibular gland-duct system and the mandible. Thus, the surgical approach to the malignant sublingual gland tumor should include the adequate management of neighboring structures. In addition, adjuvant radiation therapy provides a survival benefit for patients with malignant sublingual gland tumors, which have adverse features. This article summarizes the clinical characteristics and unique features of malignant sublingual gland tumors based on previous reports, and provides clinical information regarding the sublingual gland tumors to increase awareness of primary physicians as well as patients.