Recurrent Symptoms in Lumbar Disc Herniation with Concomitant Schwannoma: The Role of Tumor Microenvironment and...

Lumbar intervertebral disc herniation commonly causes back pain and radiculopathy, but its coexistence with paravertebral tumors is rare. Nerve sheath tumors are the most frequent, yet their simultaneous occurrence with disc herniation producing similar symptoms is uncommon. Such cases are diagnostically and therapeutically challenging, as overlapping features may obscure the pathology and delay treatment.

This is a rare case of a 33-year-old male presenting with low back pain and bilateral radiculopathy, left greater than right, for 1 month with positive straight leg raising test. Magnetic resonance imaging revealed an L5-S1 central disc herniation with an additional left paravertebral soft-tissue mass. Due to persistence and worsening of symptoms, even after conservative trail, he underwent endoscopic discectomy, and he had good relief of radicular pain. Postoperatively, after discontinuation of non-steroidal anti-inflammatory drugs, he developed left loin pain radiating to the thigh with tenderness at left loin. Excision biopsy of the mass confirmed a schwannoma. Following surgery, his symptoms improved markedly.

Sciatica may arise from lumbar disc herniation or from nerve sheath tumors, including intramuscular schwannomas. Schwannomas comprise multiple cellular elements - such as Schwann cells, axons, and macrophages - that create a complex "tumor microenvironment." The dynamic interactions within this microenvironment play a key role in the development of symptoms. Anti-inflammatory agents can transiently suppress these processes; however, symptom recurrence, including back pain and radiculopathy, is often observed after their discontinuation.