Unexpected Presentation of Perianal Granular Cell Tumor in a Young Woman.

Granular cell tumors originate from Schwann cells of the soft tissues and are rarely observed in the perianal region. Often, correct diagnosis can be challenging owing to nonspecific clinical symptoms and imaging characteristics, as well as its ability to mimic other malignant lesions histologically. We describe the case of a previously healthy 36-year-old woman who presents with a slow growing, painless lump in her perianal region who underwent surgical excision and was found to have a granular cell tumor on microscopic evaluation. This case highlights the importance for radiologists, pathologists, surgeons, and other health care providers to be aware of this rare neoplasm and consider it in the differential diagnosis when encountering perianal masses.