Median nerve schwannoma

A rare case of a median nerve schwannoma: Case report

A median nerve schwannoma is an uncommon type of tumor that develops from Schwann cells in the peripheral nerves. We present a case report of a young prisoner with a rare median nerve schwannoma presenting as a swelling on the anterior aspect of the right wrist along the radial edge, with associated paresthesia and a positive Tinel's sign. The case was diagnosed using MRI which showed the target sign of biphasic contrast enhancement in both the mass's center and periphery as well as distinct encapsulation. The mass was managed with surgical excision which confirmed the mass to be a neurilemmoma. The radiological finding for neurinomas are not specific and the diagnosis cannot be established unless an excision is made, as neurinomas share common radiological signs with other peripheral nerve tumors and vascular tumors. This case highlights the importance of considering nerve sheath tumors, however rare, in the differential diagnosis of wrist masses, even in young patients with no history of trauma.

Median nerve schwannoma with a diagnostic delay of 8 years: a case report

Introduction

Schwannomas are benign tumors of the peripheral nerve sheath, and the median nerve is the most commonly involved nerve. These benign tumors of the peripheral nerve sheath are very rare; they are clinically and radiologically similar to most other benign swellings of the hand; thus, they are often misdiagnosed.

Case Presentation

A 41-year-old lady presented with an 8-year-long history of swelling over the distal forearm. The tumor measured 3.5×3.5×3.5 mm and was located over the flexor aspect of the distal part of her right forearm. Schwannoma was suspected from the clinical presentation and imaging, but the final diagnosis was established only after the surgery and histopathological analysis. At the follow-up after 1 year, the patient is doing well and her symptoms have not recurred.

Conclusion

Imaging characteristics of schwannoma can be misinterpreted as some other condition, making the preoperative diagnosis very difficult and important. Thus, clinicians should be aware of such swellings, especially those that have been unnoticed or misdiagnosed, and provide optimal diagnoses to confer good outcomes.