86 Rare but Real: Adrenal Ganglioneuroma Mimicking Malignancy –Two Cases from single Institution

Introduction/Objective Ganglioneuromas are rare, benign tumors arising from neural crest-derived sympathetic ganglion cells, with adrenal involvement in < 5% of cases. Typically, non-functional and incidentally discovered, they can mimic malignant adrenal tumors like pheochromocytoma or adrenocortical carcinoma. Accurate diagnosis is vital due to excellent outcomes after surgical removal. We present two adult cases of adrenal ganglioneuroma over 11 years at a single institution, highlighting diagnostic complexity. Methods/Case Report Case 1: A 49-year-old male with hypertension and syncope had a 2.7 cm left adrenal mass concerning for pheochromocytoma. Inconclusive labs led to laparoscopic adrenalectomy. Case 2: A 35-year-old female with PCOS and neurological symptoms was found to have a 5.4 cm right adrenal mass during unrelated imaging. Radical adrenalectomy was performed due to suspicion of carcinoma. Grossly, both tumors were firm, tan-white, and lacked necrosis. Microscopy showed Schwann cell fascicles and mature ganglion cells within adipose tissue, with preserved adrenal cortex. No malignancy was evident. Results NA Conclusion Adrenal ganglioneuromas are rare, benign tumors that mimic malignant adrenal neoplasms on imaging. Diagnosis is challenging, especially in adults with atypical symptoms. Mature adipose tissue may obscure findings. Histopathologic evaluation is essential for confirmation. Accurate diagnosis ensures proper management and avoids unnecessary treatment, given their excellent post-surgical prognosis.