Natural History of Brachial Plexus, Peripheral Nerve, and Spinal Schwannomas

Abstract

BACKGROUND: Management of sporadic schwannomas is often dictated by a patient's clinical presentation and the tumor's behavior. For patients who are managed nonsurgically, there are little data available about the expected natural history. OBJECTIVE: To evaluate the natural history and growth patterns of extracranial schwannomas including tumors of the distal peripheral nerves, spine, and brachial plexus. METHODS: A retrospective review was performed to identify patients with nonsyndromic extracranial schwannomas at a single tertiary care institution diagnosed between 2002 and 2019. Patient data and tumor characteristics including volume were recorded. RESULTS: Two hundred twenty-seven patients were identified (mean age 51 years, 42% male, average of 27.8-month follow-up). Tumor location was distal peripheral nerve in 82, brachial plexus in 36, and paraspinal in 109. At the time of diagnosis, peripheral lesions were significantly larger than spinal (59 m 3 vs 13 cm 3 ) and brachial plexus lesions (15 cm 3 ). Distinct growth patterns were seen with both distal peripheral nerve and spinal lesions; 34/82 peripheral nerve lesions had fast growth (β = 0.176%/day), and 48 had slow growth (β = 0.021%/day; P < .01). Spinal schwannomas similarly had 30 fast-growing (β = 0.229%/ day), 16 moderate-growing (β = 0.071%/day), and 63 slow-growing (β = 0.022%/day; P = .03) subtypes. The brachial plexus had relatively homogeneous growth patterns (β = 0.065%/day). Females had 2.9 times greater odds of having the fast-growing subtype. CONCLUSION: Distinct growth patterns were seen in extracranial sporadic schwannomas based on tumor location and patient demographics. Fast (>80% volume change per year) vs slow (5%-10% per year) tumor growth can often be ascertained within 2 follow-up images. Awareness of these patterns might have implications for patient counseling and therapeutic decision-making.

Approaches to Incidental Intradural Tumors of the Spine in the Pediatric Population

“…They divided their cohort between growing and stable lesions, recommending careful follow-up of tumors growing more than 2.5% of their volume annually given the risk of continued expansion and aggressive behavior. Lubelski et al [29] studied the natural history of 109 spinal schwannomas, observing that 63 were slow growing while 30 were fast growing. Although most of the tumors were slow growing, at least two follow-up images are recommended to determine the anticipated growth trajectory given the inherent variability across patients with spinal schwannomas.…”

Clinical evaluation of augmented reality-based 3D navigation system for brachial plexus tumor surgery

“…The anatomy of the brachial plexus region is complex, with major structures such as nerves and blood vessels overlapping and crossing each other [ 1 ]. Compression of normal organs and neovascularization by brachial plexus tumors adds further complexity to this region, making the management of these tumors challenging for surgeons [ 2 , 3 ]. Current surgical principles advocate for preserving nearby functional nerves while attempting to completely resect the tumor, which requires personalized and high-quality surgical plans based on patient-specific anatomy before surgery, as well as precise navigation during surgery [ 4 ].…”

Ultrasound-guided brachial plexus nerve block in a patient with a left palmar schwannoma: A case report

“…Schwannomas are histologically benign tumors with a very low risk of spontaneous malignant transformation. [ 1 ] Ultrasound for peripheral nerve localization and ultrasound-guided regional anesthesia are becoming increasingly popular. That increased interest also implies the necessity of choosing the best type of regional anesthesia.…”