# A Rare Case of Lipidized Fibrous Histiocytoma of the Oral Cavity

## TL;DR

This paper reports the second case of lipidized fibrous histiocytoma in the oral cavity, specifically in the buccal mucosa, highlighting its rare occurrence and diagnostic challenges.

## Contribution

The paper presents the first documented case of lipidized fibrous histiocytoma in the buccal mucosa and emphasizes the importance of immunohistochemistry for accurate diagnosis.

## Key findings

- Lipidized fibrous histiocytoma was identified in the buccal mucosa with characteristic histological features.
- Immunohistochemical analysis showed CD68 positivity in spindle and foam cells, with focal Factor XIIIa positivity and negative bcl-2 staining.
- Complete excision of the lesion resulted in no recurrence, suggesting curative potential with proper treatment.

## Abstract

Benign fibrous histiocytoma (FH) is a common cutaneous tumor that rarely occurs in the oral cavity. Lipidized FH is an uncommon variant characterized by abundant foam cells in collagenized stroma. To our knowledge, only a single case of oral lipidized FH affecting the tongue has been reported. We examine a case of lipidized FH in the buccal mucosa of a patient presenting with a gradually enlarging, pedunculated lesion measuring up to 26 mm. A histological examination revealed a well-marginated but unencapsulated tumor with a Grenz zone, hyalinized stroma, and central foam cell aggregation. Immunohistochemically, the spindle and foam cells were CD68-positive, with focal Factor XIIIa positivity and negative bcl-2 staining. The lesion was completely excised, and no recurrence was observed. To our knowledge, this is the second reported case of oral lipidized FH and the first case in the buccal mucosa. Given its rarity and histological overlap with other xanthomatous lesions, accurate diagnosis is crucial with immunohistochemistry. Complete excision appears to be curative; however, a long-term follow-up is recommended, considering the subtype of fibrous histiocytoma developing in the orofacial region.