Neuromuscular Choristoma of the Brachial Plexus Presenting as a Supraclavicular Mass in a Pediatric Patient: A Case Report.

CASE: This case demonstrates a 2-year-old boy with a rare benign supraclavicular mass diagnosed as neuromuscular choristoma through open biopsy. Postoperatively, he underwent semiannual surveillance with ultrasound without development of neurological complaints, limb deformity, or recurrence at 2-year follow-up.

CONCLUSION: Neuromuscular choristoma involving the brachial plexus is a rare tumor that should be in the differential diagnosis of pediatric peripheral nerve-based tumors. The intimate association with neural elements limits complete resection. Therefore, open biopsy with partial resection is recommended. While postoperative fibromatosis may occur, open biopsy remains the gold standard for definitive diagnosis. Ultrasound can be used to monitor recurrence.