Adrenal Schwannoma: A Rare Incidentaloma

Adrenal schwannomas are very rare tumours that are difficult to diagnose preoperatively. A 42-year-old male presented with epigastric pain and indigestion. He had history of repeated operations for recurrent facial swelling on both sides of face diagnosed as Angiolymphoid Hyperplasia with Eosinophilia (ALHE). Physical examination revealed right facial swelling. Laboratory tests showed no evidence of hormonal hypersecretion. CECT abdomen showed a well-defined heterogenously enhancing right adrenal mass (5x4cm). Patient underwent right adrenalectomy. Histopathology revealed adrenal schwannoma, confirmed by immunohistochemistry (IHC) showing diffuse expression of S-100. Fine-needle aspiration biopsy of facial lesion confirmed ALHE recurrence. Less than 35 cases have been reported. Diagnosis of adrenal schwannoma on imaging studies is very difficult and surgical resection when performed for non-functioning adrenal masses >4cm clinches the diagnosis. Adrenal schwannoma is highly uncommon and was incidentally associated with recurrent ALHE.