Background: Adrenal oncocytomas are uncommon, nonfunctioning tumors occurring most often in endocrine organs.
Case: A 32-year-old woman presented at 25 weeks' gestation complaining of right flank pain. Abdominal ultrasonography and computed tomography revealed a 9 x 10-cm solid right-sided adrenal mass. Endocrine evaluation was normal. At 36 weeks' gestation, she underwent cesarean followed by resection of the adrenal mass. Histopathologic and ultrastructural studies revealed a benign adrenocortical oncocytoma.
Conclusion: Although rare, adrenocortical oncocytomas should be included in the differential diagnosis of solid, nonfunctioning, adrenal tumors in pregnancy.