Abstract

Background: Schwannomas, along with meningiomas, constitute the most common type of intradural extramedullary tumors. They are rare, typically benign tumors that originate from Schwann cells. Symptoms and signs attributed to these tumors may include back/radicular pain, focal motor and/or sensory deficits, and bowel/bladder dysfunction. It is essential to obtain pathological confirmation of this lesion and to differentiate it from other benign (i.e., neurofibromas, lipomas, ganglion cysts, meningiomas, and giant cell tumors), and/ or infrequently malignant lesions (i.e., malignant peripheral nerve sheath tumors, and sarcomas). Epithelioid Schwannomas/Benign Epithelioid Schwannomas (BES) is a benign, rare histologic subtype of schwannoma that resembles epithelial cells and lacks classic features such as Antoni A and Antoni B areas.

Case Description: A 29-year-old female presented with 1 year of severe, constant, sharp back pain (i.e., 5–10/10) that radiated down the left lower extremity. She also experienced bilateral leg numbness and tingling, along with weakness in the hips and right lower extremity. Diclofenac failed to provide any pain relief. Notably, symptoms progressed despite the utilization of physical therapy. Her neurological examination showed mild weakness (4+/5) in the left tibialis anterior and extensor hallucis longus distributions. The magnetic resonance imaging revealed a heterogeneously enhancing circumferential intradural extramedullary mass at the L2 level that caused cauda equina compression. The patient underwent an L1–L2 laminectomy, which was recommended for tumor resection. Pathologically, the lesion proved to be a BES; the epithelial cells stained positive for S-100. Three months postoperatively, the patient is asymptomatic.

Conclusion: BES is a rare subtype of schwannoma. Patients with these lesions should undergo gross total tumor resection to achieve the best long-term postoperative outcomes.

Keywords: Epithelioid schwannoma, Gross total removal, Laminectomy, Lumbar schwannoma, Operative video, Pathology, Surgical resection

Video 1

Annotations[1-6]

0:07 – Case presentation

1:13 – Neuroimaging findings

2:35 – Surgical steps

3:15 – Surgical video

6:19 – Background

7:24 – Review of clinical outcome

7:58 – Pathology

8:33 – References

Ethical approval:

Institutional Review Board approval is not required.

Declaration of patient consent:

The authors certify that they have obtained all appropriate patient consent.

Financial support and sponsorship:

Nil.

Conflicts of interest:

There are no conflicts of interest.

Use of artificial intelligence (AI)-assisted technology for manuscript preparation:

The author confirms that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.

Video available on:

https://doi.org/10.25259/SNI_267_2025

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