Intraneural reticular perineurioma of the hypoglossal nerve.

BACKGROUND Intraneural perineurioma or reticular perineurioma, which is 1 variant of extraneural perineurioma, has been rarely reported in the head and neck region. METHODS We report a case of a 52-year-old woman who wasseen with a swelling in the neck. A mass was found located on the medial aspect of the left submandibular gland and was palpated with a sponge-like texture. The mass was seen as a homogenous semisolid lesion on CT and ultrasound examination. RESULTS Surgical exploration revealed expansion of the hypoglossal nerve. Microscopically, the tumor showed both pseudo-onion bulb, which is a feature of intraneural perineurioma, and reticular pattern with microcysts, which is a feature of reticular variant of extraneural perineurioma. The tumor cells were immunopositive for epithelial membrane antigen and human erythrocyte glucose transporter-1 (GLUT-1). CONCLUSION An intraneural reticular perineurioma of the hypoglossal nerve should be included in the differential diagnosis of submandibular swelling.