Ectopic Adrenal Cortical Tissue in the Ovary: A Rare Incidental Histopathologic Finding

Ectopic adrenal cortical tissue (EACT) is an uncommon developmental heterotopia and is exceptionally rare in the ovary of adult women. A 52-year-old woman, 6 years after menopause, was evaluated for progressive enlargement of a uterine leiomyoma and postmenopausal spotting. Transvaginal ultrasonography and pelvic magnetic resonance imaging demonstrated multiple uterine leiomyomas but no adnexal mass or endometrioma. During total laparoscopic hysterectomy with bilateral salpingo-oophorectomy, dense adhesions between the sigmoid colon and posterior cul-de-sac were unexpectedly encountered. Histopathologic examination of the adhesion-related tissue revealed neither endometriosis nor significant inflammatory change. Microscopic examination of the ovary identified a 1.9 mm, sharply circumscribed nodule composed of clear, vacuolated zona fasciculata-like cells and compact eosinophilic zona reticularis-like cells. The lesional cells showed diffuse Melan-A immunoreactivity and focal-to-patchy inhibin-α positivity, supporting adrenocortical differentiation. The findings established a diagnosis of ovarian EACT. This case emphasizes that microscopic ovarian adrenal rests may be radiologically occult and should be distinguished from ovarian steroidogenic neoplasms by integrating clinical, morphologic, and immunohistochemical findings.