Granular Cell Tumors are Very Rare but Important Vulvar Masses that should not be Overlooked

Granular cell tumors are uncommon neoplasms of neural origins affecting the submucosal and subcutaneous tissue in the tongue, neck, head, and genitals. Vulvar tumors represent about 15% of the cases and present as solitary painless swellings with or without accompanying local manifestations. It is more common in Afro- American women in their fourth to fifth decade.

They are predominantly benign tumors with malignant variants in 1-3% of cases. Malignant forms are aggressive, therapy-resistant, and can metastasize. Wide excision with clear margins is the recommended curative treatment. More than 33% of excisions have positive margins, increasing the risk for local recurrence from 2% to about 20%. The combined risk of recurrence and malignant transformation is a reason for recommending wide re-excision in cases with positive margins. We recommend a preoperative biopsy for every solid vulvar lump in order not to miss such a rare diagnosis and to correctly plan treatment.