Primary Carcinoid Tumor of the Central Nervous System: A Rare Case Report with a Diagnostic Challenge.

Carcinoid tumors (CTs) are slow-growing neuroendocrine neoplasms that may arise in any part of the body. They usually affect the lungs or gut. Primary intradural extramedullary CTs of the central nervous system are rare; few cases have been reported. This case report describes a 36-year-old patient with lower back discomfort, weakness, and lower leg pain for 8 months. Contrast-enhanced magnetic resonance imaging of the lumbosacral spine, from the lower L3 vertebral level to the L4-5 disc level, revealed a 4.5 cm × 2.5 cm × 1.5 cm intradural mass lesion. The main differential diagnoses were on clinical and radiographic examination: nerve sheath tumors, meningiomas, and myxopapillary ependymomas. The tumor was excised en bloc after an L3-L5 lumbar laminectomy. Histomorphology and immunohistochemistry made a definitive diagnosis of CT of the lumbar spine. Two years after surgery, there was no clinical or radiological evidence of tumor recurrence or metastasis. The present case study is intended to effectively diagnose and treat spinal intradural extramedullary CTs.