Polypoid non-neural granular cell tumor of the oral cavity: case report and literature review

Aim

To report a case of non-neural granular cell tumor (NN-GCT), an uncommon neoplasm, with only six studies worldwide describing cases involving the oral cavity.

Methods

A 26-year-old male patient with an erythematous, firm, polypoid nodule in the floor of the mouth that exhibited areas of ulceration and mild bleeding to the touch. A biopsy was performed to aid in the diagnosis.

Results

Based on the histopathological and immunohistochemical results (vimentin +, CD68 +, S100 -), the diagnosis was compatible with S100-negative (primitive polypoid non-neural) granular cell tumor. No recurrence was observed over two years of follow-up.

Conclusion

The diagnosis of NN-GCT is extremely challenging because this tumor shares histological and immunophenotypic features with many benign and malignant tumors. Although oral NN-GCT may exhibit unusual and atypical histological features, it has an indolent behavior. Thus, until more cases of oral involvement are reported, complete resection and close follow-up are recommended.

Keywords
Granular cell tumor; S100 proteins; Immunohistochemistry; Mouth neoplasms