Adrenocortical Oncocytoma: A Case Report and Review of Literature

Kato T,Ichikawa T,Komiya A,Kamiya N,Ito H,Ishikura H

doi:10.21767/2472-5056.100016

Abstract

A 53-year old man was found to have a right incidental adrenal mass measuring 5 × 6cm. The patient underwent laparoscopic right adrenalectomy and the tumor was surgically removed. The histological diagnosis was oncocytoma, the cytoplasm of which was intensely eosinophilic with abundant granule. Oncocytoma of the adrenal gland is rare disease.Recently, the advancement of imaging techniques, especially the routine use of computed tomography (CT) and magnetic resonance imaging (MRI) lead to increased number of incidentally discovered adrenal masses including adrenocortical oncocytoma. In this report, the clinical features of adrenocortical oncocytomas are discussed.

Highlights

Oncocytoma is an epithelial neoplasm composed of oncocytic cells whose cytoplasm is packed with mitochondria [1]
We report a case of adrenocortical oncocytoma and the clinical features of adrenocortical oncocytomas are discussed
High mitotic rate, atypical mitoses, and venous invasion are defined as major criteria and larger sized tumor (>10 cm and/or >200 g), necrosis, capsular invasion, and sinusoidal invasion are defined as the minor criteria

Summary

Introduction

Oncocytoma is an epithelial neoplasm composed of oncocytic cells whose cytoplasm is packed with mitochondria [1]. This tumor is characterized by a histologic pattern of large eosinophilic cells with a granular cytoplasm. Oncocytoma of the adrenal gland is relatively rare [2,3]. The tumor cells showed specific findings of the oncocytomas. A few atypical cells with hyperchromatic nuclei were diffusely scattered, which suggests malignant potential. Mitotic rate of these atypical cells was greater than 5 per 50 high power fields. To confirm adrenocortical origin, immunostaining for adrenal 4 binding protein (Ad4BP), a transcription factor of steroidgenesis, was performed [4]. The patient was alive and well without evidence of recurrence 10 years after surgery

Discussion

Conclusion