Subgemmal neurogenous plaque of posterolateral region in tongue: A case report and review of literature.

INTRODUCTION: The subgemmal neurogenous plaque is a well-defined subepithelial neural plexus associated with taste buds, located within foliate, fungiform, and circumvallate papillae of the human tongue, that is poorly known by dentists and medical professionals. The hyperplasia of subgemmal neurogenous plaque may occur and it manifests as a papule, nodule, plaque, or ulcer in the lateral posterior border of the tongue inducing the overdiagnosis of reactive, cystic, or neoplastic lesions. The aims of this study are to report a case of a patient with subgemmal neurogenous plaque, and to provide a comprehensive review of other subgemmal neurogenous plaque in the posterolateral tongue with challenging diagnosis. PRESENTATION OF CASE: A 28-year-old female with a little yellowish nodule, asymptomatic, located in posterior left lateral border of the tongue. Accurate diagnosis was based in excisional biopsy and histopathological examination showing a superficial neurofibroma-like pattern, and a neuroma-like in the deep zone. The final diagnosis was subgemmal neurogenous plaque. DISCUSSION: The subgemmal neurogenous plaque has an erythematous nodule or papule in the border of the tongue that are frequently misdiagnosis as foliate papillitis and lymphoepithelial cyst. Despite the subgemmal neurogenous plaque be considered a normal structure, the biopsy is recommended for differential diagnosis with other benign or malignant lesions in tongue. CONCLUSION: Contributing with the dentists and medical professionals in their clinical practice, we reviewed the literature and added a case of subgemmal neurogenous plaque in the posterolateral region of the tongue, highlighting the importance of its recognition to avoid misdiagnosis.