Secretory carcinoma of the minor salivary gland in the lip with ETV6-NTRK3 fusion: Case report and literature review

Abstract

Salivary gland tumors are histologically diverse, and there are numerous types of both benign and malignant tumors, including secretory carcinoma (SC). Because fusion gene expression in SC is similar to that in mammary SC, SC was classified independently in 2017. Most SCs arise in the parotid gland and rarely in the minor salivary glands, such as those in the lip, palate, or buccal mucosa. Herein, we present a rare case of primary SC of the minor salivary gland in the lip with the ETV6-NTRK3 fusion gene, validated as an oncogenic target in cross-organ therapy. The patient underwent surgical treatment, and no recurrence or metastasis has been observed 13 months postoperatively. While the salivary gland tumor had inadequate evidential methods except for surgery until recently, the genetic analyses may offer patients a new choice of therapy for NTRK inhibitor-based pharmacokinetic-guided strategies and might contribute to the diagnosis and prognosis of salivary gland tumors.