# Adenoid cystic carcinoma of the retromolar pad region: A case report

## TL;DR

A rare case of adenoid cystic carcinoma in the retromolar pad was diagnosed after initial misidentification as a benign tumor.

## Contribution

This case report highlights the rarity and potential misdiagnosis of ACC in the retromolar pad region.

## Key findings

- ACC in the retromolar pad is extremely rare and can be misdiagnosed as a benign mucocele.
- Pathological examination confirmed ACC after initial clinical and radiographic suspicion of a benign mass.
- Long-term follow-up over 54 months showed no recurrence, emphasizing the importance of thorough monitoring.

## Abstract

Adenoid cystic carcinoma (ACC) is one of the most common salivary gland malignancies, mostly occurs in the major and minor salivary glands in the oral and maxillofacial region. The development of ACC in the retromolar pad is extremely rare, which limits establishing proper diagnosis and management.

A patient described a 2-month history of finding a mass behind the lower left posterior teeth. Based on the physical examination and radiographic findings, we got an initial impression of a benign mucocele, the nature of which was to be investigated further. Pathological examination of the resected tissue resulted in a diagnosis of ACC. Follow-up visits showed no recurrence during the subsequent 54 months.

In cases with an uncertain diagnosis based on medical history, clinical features and imaging examinations, it is important to proceed carefully with the possibility of a tumor in mind.

ACC in the retromolar pad is rare and can be easily misdiagnosed. Clinical, radiographic, and pathological evidence confirm a definitive diagnosis. Long-term follow-up is important for the full analysis of ACC treatment.

•Adenoid cystic carcinoma is one of the most common malignant tumors of the salivary gland.•Adenoid cystic carcinoma in the retromolar pad has not been reported and easily misdiagnosed.•Given the prognosis of ACC, actively treatment of the primary lesion and thorough follow-up are necessary.

Adenoid cystic carcinoma is one of the most common malignant tumors of the salivary gland.

Adenoid cystic carcinoma in the retromolar pad has not been reported and easily misdiagnosed.

Given the prognosis of ACC, actively treatment of the primary lesion and thorough follow-up are necessary.