Neurilemmoma of median nerve

Neurilemmomas constitute one of the most common tumors of peripheral nerves. Rarer amongst them is their occurrence in median nerve in the region of arm. A sixteen-year-old female presented with painless mass in right arm which was non-tender on palpation with positive Tinel's sign and no motor or sensory deficit in the affected arm. Ultrasound examination revealed an eccentrically arising mass of size 19 × 11 mm along median nerve. MRI study revealed a mass homogenously isointense on T1 weighted images and hyperintense in T2 weighted images placed eccentrically in relation to median nerve in arm. Excisional biopsy under loupe magnification was carried out which revealed the mass to be neurilemmoma. This slowly growing benign tumor of peripheral nerves with an incidence of 5% with 14% involvement of Median nerve can be enucleated from the nerve with little or no damage. In spite of advanced imaging studies the mass cannot be differentiated preoperatively from another peripheral nerve sheath tumor neurofibroma. Both these tumors although bearing some clinical and imaging resemblance carry different intraoperative findings, histopathological features and post-operative results.