Incidentally identified adrenal lipoma: case report and review of related literature.

Objective: To report a case of an incidentally identified adrenal lipoma in a 68-year-old man with flank pain and hypertension.

Methods: The clinical, computed tomographic, and magnetic resonance imaging findings in this patient are described, and the pathologic features of the tumor are characterized. Moreover, the related literature is reviewed and summarized.

Results: The patient had undergone coronary artery bypass grafting, had a prosthetic heart valve, and required systemic anticoagulation. Computed tomography showed a well-circumscribed left adrenal lesion with evidence of scattered foci of macroscopic fat; these findings were confirmed on magnetic resonance imaging. After laparoscopic left adrenalectomy, pathologic examination revealed a well-circumscribed, fatty, 7-cm adrenocortical-based tumor, which weighed 135 g. Histologic sampling disclosed mature adipose tissue without evidence of myeloid heterotopy or features of malignant involvement, and adrenal lipoma was diagnosed. On the basis of our review of the English-language literature, this tumor is the 11th reported case of adrenal lipoma. The vast majority of these tumors have been asymptomatic and identified incidentally on imaging or at autopsy. A minority of patients have had a history of hypertension.

Conclusion: With the increased utilization and sensitivity of abdominal imaging techniques, identification of nonfunctional adrenal tumors has become more frequent. Adrenal lipoma should be included in the differential diagnosis of lipomatous adrenal tumors.