Intraspinal clear cell meningioma without dural attachment: A case report and literature review.

RATIONALE Clear cell meningioma (CCM) is one of the rarest but most aggressive forms of meningioma, with a tendency to occur at a high recurrence rate. Intraspinal CCM, especially the nondura-based type, is even rarer than the intracranial CCM. PATIENT CONCERNS We report a case of a 45-year-old woman who presented with a 1-month history of episodic pain in the lower back and in both thighs in the front side. Femoral nerve stretch tests were positive on both sides. Magnetic resonance imaging (MRI) demonstrated an intradural tumor at the L3 level, which was isointense on T1- and T2-weighted images (WI) and homogeneously enhanced on gadolinium-contrast T1 WI. DIAGNOSES The space-occupying lesion was pathologically confirmed as CCM. INTERVENTIONS During surgery, we found that the tumor adhered to a nerve root, without dural attachment. The nerve root was partially removed to achieve complete resection. OUTCOMES The pain disappeared after the operation. The 1 year follow-up MRI revealed no evidence of tumor recurrence or metastasis. LESSONS Nondura-based intraspinal CCM is easier to completely remove, and such complete removal should be achieved during the first operation. Although the recurrence rate of this particular type of meningioma appears to be lower than that of other types, close clinical and radiological follow-up is necessary.