# Rare Tumors of Oral Cavity: A Case Report and Literature Review on Secretory Carcinoma of Minor Salivary Glands

## TL;DR

This paper reports two rare cases of secretory carcinoma in the mouth and highlights the importance of accurate diagnosis and treatment.

## Contribution

The study contributes two new case reports of secretory carcinoma and emphasizes the need for precise diagnosis using immunohistochemistry and molecular analysis.

## Key findings

- Secretory carcinoma was accurately diagnosed in two patients after initial misdiagnosis.
- Immunohistochemical and molecular analyses confirmed the presence of ETV6–NTRK3 gene fusion in one case.
- Surgical excision followed by monitoring was effective in preventing recurrence in both cases.

## Abstract

The primary objective of this study is to report and analyze two rare cases of secretory carcinoma (SC) of the minor salivary glands, focusing on their diagnostic and therapeutic work‐up. The study aims to enhance scientific knowledge about SC, which is crucial for developing targeted therapies and ensuring precise diagnosis, especially differentiating it from acinic cell carcinoma (ACC).

The study involved a detailed examination of two patients diagnosed with SC of the minor salivary glands. Clinical examinations, histological investigations, and immunohistochemical analyses were conducted. The treatment approach included surgical excision of the lesions followed by regular follow‐ups to monitor for recurrence. Immunohistochemical analysis was performed to identify the presence of markers such as GATA3, SOX‐10, NTRK, mammaglobin, and others.

Two cases are shown: a case of a 76‐year‐old male with a lesion in the hard palate was initially misdiagnosed as leukoplakia. After surgical excision and histological examination, the lesion was identified as SC. The patient underwent follow‐up examinations, including MRI and CT scans, which showed no recurrence, and another case of a 39‐year‐old female with a nodule in the superior left vestibule underwent surgery to remove the nodule. Histological and immunohistochemical analyses confirmed SC, showing a high proliferation index and presence of the ETV6–NTRK3 gene fusion. Follow‐up imaging showed no signs of disease recurrence.

The study underscores the importance of precise diagnosis and differentiation of SC from ACC. Surgical excision followed by regular monitoring is effective in managing SC. Immunohistochemical and molecular analyses are crucial for accurate diagnosis. The findings contribute to the growing body of evidence on SC and highlight the potential for developing more targeted therapies. Further research is needed to establish clear guidelines for follow‐up duration and treatment protocols.

This article emphasizes how secretory carcinoma of salivary glands, which is not always indolent, should not be taken lightly when diagnosed. Specialized pathology knowledge is essential to understand the histopathological trait, leading to targeted therapy.