SUN-168 Diagnosis of 46,XY Differences in Sex Development in a Patient with Adrenocortical Carcinoma

Abstract Disclosure: K. Baez: None. M. Aoun: None. I. Blanco: None. R.R. Savian: None. A. Razzeto: None. C.V. Villabona: None. 61-year-old patient with a history of adrenocortical carcinoma, leading to ACTH - independent Cushing syndrome s/p adrenalectomy, hypertension, fatty liver, hyperlipidemia, and asthma, presented for follow-up in the outpatient endocrinology clinic. The patient was incidentally found to have a large left adrenal mass in 2016 on a CT scan performed for symptoms of pyelonephritis. Laboratory evaluation revealed hypercortisolism and hyperandrogenemia with normal metanephrines and normetanephrines. The patient underwent left laparoscopic adrenalectomy in 2018, she was found to have an adrenocortical carcinoma. She underwent radiation therapy, and received mitotane treatment for two years along with hydrocortisone replacement therapy. She has primary adrenal insufficiency treated with hydrocortisone and fludrocortisone. The patient, on review of systems, reported a history of primary amenorrhea and delayed development of secondary sexual characteristics —absent terminal hair in the axilla and pubis. As a child she reported she had multiple tests and she underwent a surgical intervention to dilate the vaginal canal but she has been unaware of her condition. An evaluation in her teenage years revealed an absence of ovaries and uterus. The patient was started on estrogen replacement therapy, which she took late teen years until her early 20s. She reported difficulties having sexual intercourse. Additionally, on family history she reported her parents were first cousins and the patient has color blindness, this detail on her history ( X-linked recessive inheritance pattern disorder ) let us suspect she had a 46 XY karyotype. On laboratory tests, besides having adrenal insufficiency her estradiol and testosterone levels were low with high gonadotropins. Chromosomal analysis revealed a 46,XY karyotype without mosaicism, as we suspected. Conclusion: We report a rare case and first case described in the literature of a patient with gonadal dysgenesis with an adrenocortical carcinoma causing Cushing's Syndrome. Presentation: Sunday, July 13, 2025