Only 17 cases of oncocytic adrenocortical carcinoma have been reported in the English literature. Here, we report an incidental case of oncocytic adrenocortical carcinoma. The patient was a 69-year-old man with the chief complaint of abdominal pain. Abdominal computed tomography revealed a left adrenal tumor. No hormonal symptoms were observed. The excised tumor was whitish, encapsulated, and 75 × 60 × 45 mm in size. Large polygonal tumor cells were arranged in a generally diffuse architecture and...