Solitary Intraneural Pseudoperineuriomatous Proliferation of the Tongue

We report here a 35-year-old Caucasian female with 1 month history of a painless, sessile, non-ulcerated, and moveable lesion in the left border of the tongue. Histologically, the lesion was consistent with an intraneural pseudoperineuriomatous proliferation (IPP), a rare, usually solitary, and likely reactive process mimicking, for the presence of “pseudoonion bulbs,” intraneural perineurioma. Pathologists, otolaryngologists, maxillofacial surgeons, and dentists have to be aware of it in order to avoid an inappropriate diagnosis. Perineuriomas are uncommon and almost always benign peripheral nerve sheath tumors composed of perineural cells.Two main variants exist: extra-neural perineurioma (EP), which usually involves soft tissues and skin, and intraneural perineurioma (IP), which is typically restricted within the peripheral nerve boundaries