Intracapsular Enucleation of Brachial Plexus Schwannoma With Intraoperative Neuromonitoring: A Case Series Study and a Review of Literature

Abstract

Objective: Brachial plexus schwannoma (BPS) is a rare clinical entity that poses a significant challenge for head and neck surgeons due to its neuroanatomical complexity and potential severe complications, such as major motor or sensory neurological deficits or pain of the corresponding upper extremity. This article summarizes our experience in its diagnosis and intracapsular enucleation with intraoperative neuromonitoring (INM). Methods: A retrospective review of BPS cases treated at our tertiary medical institution was conducted between April 2020 and May 2023. The clinical and demographic data were retrieved from case notes. Results: Totally, 3 cases were included. All 3 patients were male, aged 43 to 54 years (median age = 52). The presenting symptom was a palpable supraclavicular mass in all these cases (2 on the left side and 1 on the right side). Neuromonitoring was performed with a 4-channel nerve integrity monitor, with the electrodes placed in the upper arm and forearm muscles, as demonstrated in the literature. After exposing the mass and identifying its origin from the brachial plexus, a unipolar stimulating probe was used to stimulate the tumor surface or the nerves with a 1.0-mA current, and a longitudinal incision into the tumor capsule was made along a carefully mapped line with no INM response. Then the mass was carefully exposed and meticulously dissected from its capsule to achieve an intact enucleation. Immediate postoperative neurological deficit was documented in Case 1 as a mild grasping weakness. The recovery of the other 2 patients was uneventful. The follow-up duration was 7 to 38 months (median = 8 months). The minor motor deficit of Case 1 recovered completely 1 month after surgery. No recurrence of BPS was observed. Conclusions: Intracapsular enucleation with INM could result in complete removal of BPS and minimal postoperative neurological deficit, whose recovery was quick and satisfactory.