Arvind Rawal

Tumor involvement of the brachial plexus is uncommon. The most common intrinsic neoplasms involving the brachial plexus are benign neurilemmomas and neurofibromas that are usually associated with neurofibromatosis‐1 (NF‐1). Solitary neurofibromas unassociated with NF‐1 are very uncommon. Malignant peripheral nerve‐sheath tumors (MPNST) are rare at this site, arising spontaneously or in the context of NF‐1. This presentation discusses the clinical presentation, pathology, and management of these tumors, which usually occur in young adults. MPNST are intermediate or high‐grade sarcomas with a high risk of local and distant spread. Approximately 50% of MPNST arise in patients with NF‐1, and therefore these patients should be thoroughly investigated for any new symptoms or masses. MPNST of the brachial plexus should be treated with an adequate wide local excision, with adjuvant high‐dose radiotherapy pre‐ or postoperatively. The role of chemotherapy in the treatment of MPNST is not clearly defined, but it may have some benefit in salvaging treatment failures. © 2006 Wiley‐Liss, Inc. Microsurgery 26: 80–86, 2006.

Peroneal nerve entrapment is most common in the popliteal fossa, but is rarely caused by a ganglion. Although ganglionic cysts are very common lesions, they seldom cause serious complications. Ganglionic cysts developing in the sheath of a peripheral nerve or joint capsule may cause compression neuropathy. We report on two cases of compression neuropathy of the common peroneal nerve caused by an extraneural ganglion and its evaluation with magnetic resonance imaging (MRI) and ultrasonography. The differential diagnosis should involve L₅ root pathology, a posttraumatic intraneural hemorrhage, a nerve compression near the tendinous arch located at the fibular insertion of the peroneal longus muscle, and a nerve‐sheath tumor. The combination of MRI and ultrasonography is useful for the accurate diagnosis of this condition, and it should be treated by microsurgical exploration as soon as possible.