Secretory carcinoma in labial minor salivary gland of pediatric patients. A systematic Review.

Abstract

Background:

Secretory carcinoma (SC), formerly referred to as mammary analogue secretory carcinoma (MASC), is a rare malignant salivary gland neoplasm most frequently identified in the parotid gland but also reported in minor salivary glands. It is strongly associated with the ETV6:NTRK3 fusion, which has therapeutic implications due to the advent of TRK inhibitors. Pediatric SC is exceedingly rare, with even fewer cases reported in the labial minor salivary glands, making systematic analysis crucial.

Objective:

To synthesize available evidence on pediatric SC of the labial minor salivary glands, focusing on presentation, diagnosis, management, and outcomes.

Methods:

Electronic databases (PubMed, Scopus, Google Scholar) were searched until 2025. Studies were included if they described SC of the labial minor salivary glands in patients aged ≤18 years with histopathologic and immunohistochemical confirmation. Two case reports met the inclusion criteria.

Results:

Both patients presented with upper lip masses. A 9-year-old girl had a well-circumscribed, 2 cm lesion confirmed as SC (CK7+, mammaglobin+, S100+); managed by excision with margin extension, she remained disease-free at 36 months. A 17-year-old male had a high-grade SC of the philtrum with nodal metastasis, treated by wide excision, bilateral selective neck dissection, and adjuvant chemoradiotherapy; he remained disease-free at 6 months. Both tumors displayed classical SC morphology, though molecular fusion testing was not universally performed.

Conclusions:

Pediatric labial SC is exceptionally rare but clinically significant. It should be considered in the differential diagnosis of circumscribed pediatric lip nodules. Management is primarily surgical, with aggressive multimodal therapy indicated for high-risk disease. Awareness is vital to avoid misdiagnosis as acinic cell carcinoma and to facilitate timely recognition of ETV6-NTRK3 fusions, which may enable targeted therapies.