Lower Lip Plexiform Schwannoma: Report of a Rare Case and a Literature Review.

Plexiform schwannoma is an uncommon benign neoplasm of the neural sheath characterized grossly and microscopically by multinodular growth. It is typically presented as a mobile, solitary, smooth-surfaced, and nontender mass. Histologically, schwannomas are classified into the following seven types: classical (Verocay), plexiform, cellular, cranial nerve, melanotic, degenerated (ancient), and granular cell schwannomas. In spite of the fact that plexiform schwannoma commonly occurs in the head-and-neck region, the involvement of the lip is considered to be extremely rare. Herein, we present the case of a 16-year-old boy with the schwannoma on the lower lip excised without any recurrence at 9 months after surgery.