Oncocytoma Arising From an Accessory Adrenal Gland: A Case Report

Abstract

Introduction

Accessory adrenal oncocytomas are rare. Consequently, the clinical characteristics and management of this entity remain poorly defined.

Case Presentation

A 65-year-old man presented with a retroperitoneal mass. Imaging revealed a 103 × 96 mm tumor adjacent to the left kidney. Hormonal evaluation indicated the tumor was nonfunctioning; however, dehydroepiandrosterone sulfate and neuron-specific enolase levels were elevated, and malignancy could not be excluded. The tumor was resected laparoscopically. Histopathological examination revealed oncocytic features, and immunohistochemistry demonstrated positivity for steroidogenic factor 1. The tumor was anatomically separate from the normal adrenal gland, supporting the diagnosis of an accessory adrenal oncocytoma. Based on the Lin–Weiss–Bisceglia criteria, the tumor was classified as borderline malignant potential. No recurrence has been observed during 2 years of follow-up.

Conclusion

Accessory adrenal oncocytomas are rare entities, and their accurate diagnosis requires a comprehensive, integrated approach incorporating clinical findings, imaging studies, and detailed pathological evaluation.