Schwannoma is a benign peripheral nerve sheath tumor arising from the schwann cells. The usual location of Schwannoma is in the head & neck region and the extremities. Adrenal schwannoma is an extremely rare cause of incidentaloma accounting for 0.7% of all adrenal tumors. We report a case of benign right adrenal schwannoma detected in a 43 year old female presenting with right flank pain. There were no clinical features suggestive of Cushing disease, Pheochromocytoma or primary hyperaldosteronism. Computed Tomography (CT) of the abdomen showed a heterogeneously enhancing mass of size 9*5cm. The biochemical and metabolic evaluations including endocrinology studies were unremarkable and consistent with a non functioning adrenal mass. Adrenalectomy was performed due to the large size of the tumor. Histopathological examination revealed a well circumscribed, partially encapsulated mass of size 9*7.5*5cm. Tumor was composed of fascicles of spindle cells with alternating hypercellular and hypocellular areas with mild atypia and no mitosis. Degenerative changes in the form of cystic and mucoid areas were seen. On the basis of histopathological examination the diagnosis of adrenal schwannoma was made. The diagnosis was supported by immunohistochemical positivity for S-100. Adrenal schwannoma is a rare tumor with less than 50 cases reported in the literature, and hence the significance of this case report.

Keywords:  Adrenal tumor,  Schwannoma,  Adrenal schwannoma.

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Sarita Asotra

Associate professor, Department of Pathology, IGMC Shimla, India