SAT-259 Acromegaly by Pituitary Adenoma Associated with ACTH-Independent Cushing Syndrome by Adrenal Carcinoma: Case Report

Introduction: The coexistence of acromegaly and Cushing’s syndrome is quite rare. Case reports with this association have been described in the literature, including both ACTH-dependent and ACTH-independent Cushing’s syndrome. In these cases, when considering ACTH-independent hypercortisolism, the main etiology reported is adrenal adenoma. We will describe the case of an acromegalic patient with ACTH-independent cushing syndrome due to adrenal cortical carcinoma. Clinical Case: A 62-year-old male patient with acromegaly diagnosed by headache investigation. He had a previous medical history of T2DM for 20 years, grade III obesity (BMI 40.3), hypertension, obstructive sleep apnea and depression. Initial investigation showed IGF-1 levels of 818 ng/mL (81–225), GH: 3.39 ng/mL (<0.97), prolactin diluted: 2.578 ng/mL (2.1–17, 7), LH: <0.07 mIU/mL (1.5–9.3), FSH: 0.6 mIU/mL (1.4–18.1), total Testosterone: 51 ng/dL (241- 827) Cortisol at 8 AM: 15 µg/dL, TSH: 1.54 µg/dL (0.55–4.78), free T4: 1.0 ng/dL (0.89–1.76) and brain MRI with a large expansive sella turcica process, invading the right cavernous sinus, with growth to the sphenoid sinus and suprasellar compressing the optic chiasm, suggestive of pituitary macroadenoma. He underwent transsphenoidal resection with histology confirming a prolactin and GH co-secretory pituitary adenoma with Ki-67: 5%. He started treatment with octreotide LAR (30 mg/month) and cabergoline (3.5 mg/week) and underwent 25 radiotherapy sessions. Three years after the diagnosis of acromegaly, the patient underwent CT scan of the abdomen, which identified a 3.8 cm left adrenal nodular lesion that evolved in the 12-month control exam to nodular image with lobulated contours (5.0 x 3.4 cm) and non-contrast phase density > 25 HU. At that time, he had two 24-hour cortisoluria samples: 640.9 and 637 µg/24hs (54–403) and ACTH <5.0 pg/mL (<46).The patient underwent videolaparoscopic adrenalectomy confirming the pathology of the lesion compatible with adrenal cortical carcinoma with invasion of the capsule and peri-adrenal adipose tissue and Ki-67: 20%. Even after primary resection of the adrenal lesion, the patient evolves with local and metastatic progression of the disease, dying a few months later, due to infectious complications of a new surgical approach. Conclusions: To the best of our knowledge, this is the first case of ACTH-independent Cushing’s syndrome caused by adrenocortical carcinoma in an acromegalic patient.