Granular Cell Tumor of the Intradural Extramedullary Spinal Cord : Report of Two Cases with Respect to Radiological Differential Diagnosis
A 21-year-old woman presented with a 3-month history of right arm pain and tingling. The sensory changes had been present for 10 years, but she had not received any treatment. Her symptoms were aggravated after a minor car accident. She had no relevant medical or family history. Physical examination revealed intact motor power and normal reflexes. Computed tomography (CT) showed bony erosion at the right C5 and C6 foramina, and the right vertebral artery was displaced anteriorly. MR images demonstrated a 3.5×2.3 cm dumbbell-shaped IDEM mass at C5-6 that extended to the right extraforaminal space. The tumor showed isointensity with respect to the spinal cord on T1-weighted images and homogeneous gadolinium-enhanced T1-weighted images (). Speckled dots were also observed on the T2-weighed images and gadolinium enhanced T1-weighed images. As in Case 1, the tumor showed low signal speckled dots especially on the T1 enhanced images. Complete tumor resection was performed. The histological findings showed lymphocytic infiltration around granular cells (). The tumor cells were strongly immunoreactive with S-100 protein on the immunohistochemical analysis. The postoperative course was uneventful, and the patient experienced significant relief of her tingling sensation.