Lumbar Ewing's Sarcoma Mimicking a Herniated Disc in a Young Adult: A Case Report

Ewing's sarcoma is a rare and aggressive malignancy of bone and soft tissue, most commonly affecting the pelvis and long bones of children and adolescents. Spinal involvement, particularly in young adults, is exceptionally uncommon and can present symptoms mimicking more prevalent lumbar pathologies such as disc herniation, increasing the risk of misdiagnosis and delayed treatment.

A 23-year-old male presented with progressive low back pain and bilateral L5 radiculopathy with ankle and great toe dorsiflexion weakness (MRC 4/5). Bowel and bladder function were preserved. Initially diagnosed as having a herniated lumbar disc, MRI revealed an L5-S1 mass with lytic vertebral lesions suspicious for neoplasm. The patient underwent open laminectomy without instrumentation for surgical decompression and tissue biopsy, with histopathological and immunohistochemical studies confirming a diagnosis of Ewing's sarcoma. Postoperative recovery was marked by full neurological improvement, and the patient was subsequently treated with a multimodal chemoradiotherapy regimen. At one-year follow-up, the patient remained symptom-free with no evidence of recurrence or metastasis.

Due to its rarity, standardized treatment protocols for adult lumbar Ewing's sarcoma remain elusive. This case underscores the necessity of maintaining a high index of suspicion for neoplastic etiologies, rather than defaulting to common diagnoses like disc herniation, when young adults present with progressive or atypical lumbar symptoms. Early identification, prompt surgical decompression, and aggressive multimodal chemoradiotherapy are critical for optimizing survival, especially given the difficulty of achieving negative surgical margins. Ultimately, rapid, coordinated intervention remains essential to improving outcomes.