7464 Delayed Diagnosis of Cushing’s Disease after Five Year History of Hirsutism

Abstract Disclosure: E. McBride: None. A.N. Davis: None. G. Elshimy: None. J. Vender: None. Introduction: Women may experience hirsutism for years before seeing a physician or before undergoing diagnostic testing. This case demonstrates that delayed workup of hirsutism can lead to delayed diagnosis and treatment of aggressive Cushing’s disease. Case: A 40-year-old African American female presented for initial evaluation with a 5-year history of hirsutism, which had never been evaluated, and a high cortisol level in the setting of type 2 diabetes mellitus and hypertension. She had a 60lb weight gain over 5 years, progressive hirsutism, easy bruising, and purple striae. Labs were significant for cortisol 23.86mcg/dL, ACTH 67pg/mL, HbA1c 8.9%, DHEAS 347mcg/dL, 17-OH progesterone 102ng/dL. A 1mg dexamethasone suppression test resulted in a non-suppressed cortisol of 12.64mcg/dL. She had an elevated 24 hour urine free cortisol level of 78mcg and an elevated midnight salivary cortisol with values of 474ng/dL and 396ng/dL. An 8mg dexamethasone suppression test resulted in a cortisol of 5.55mcg/dL. MRI brain pituitary protocol revealed a 6x4mm microadenoma of the pituitary gland. This is consistent with an ACTH producing pituitary adenoma (Cushing’s disease). The microadenoma was surgically removed by transsphenoidal approach. The pathology of the tumor revealed an elevated Ki-67 of 5%. Patient required hydrocortisone replacement for a couple of months that was later discontinued. Moreover, she is no longer on any medications for her diabetes, and her hypertension significantly improved postoperatively. Discussion: Hirsutism and androgen excess in women are most commonly caused by polycystic ovarian syndrome (PCOS). However, non-PCOS diagnoses, such as Cushing’s disease, should be considered as they are commonly missed due to lack of a pragmatic screening approach. Pituitary microadenomas are often benign, but 30-40% of cases are invasive and considered aggressive. Aggressiveness can be evaluated by using the tumor marker Ki67, which is a nuclear marker that reflects cell proliferation. While controversial, one proposed cutoff for aggressive pituitary adenomas is Ki67 ≥3%. The pathology of the tumor in this patient was aggressive with Ki67 of 5% This case demonstrates the importance of identifying hirsutism early in order to exclude the more dangerous causes of hirsutism such as Cushing’s disease. By early diagnosis and surgery, we may limit the progression of associated comorbidities such as diabetes mellitus and limit the growth of a potentially aggressive adenoma. Presentation: 6/1/2024