FRI206 A Rare Case Of Coexisting Acromegaly And Adrenal Cushing’s Syndrome

Disclosure: T. Chamakkala: None. T. Gallagher: None. Introduction: Acromegaly has been associated with higher risk of cancer morbidity and mortality. Acromegaly coexisting with adrenal Cushing’s disease has been rarely described in literature. We present a patient who was found to have acromegaly during evaluation for Cushing’s syndrome. Clinical Case: A 50-year-old woman presented to the office for endocrinology evaluation at the referral of PCP for elevated 24h urine cortisol level 176ug/24h. She had noticed facial plethora over several years, fatigue, and easy bruising. She had recently been diagnosed with hypertension, poorly controlled on two medications at the time of evaluation. Repeat 24h urine cortisol and midnight salivary cortisol levels were elevated; dexamethasone suppression test was positive. ACTH was <1.5pg/mL, consistent with ACTH independent hypercortisolemia. Adrenal CT showed 2.6x3cm left adrenal adenoma. She underwent left adrenalectomy and pathology showed adrenal cortical adenoma. During evaluation for Cushing’s disease and new onset hypertension, IGF1 was evaluated and found to be elevated at 354ng/mL. She additionally endorsed symptoms of worsening carpal tunnel syndrome and increasing ring size. After adrenalectomy, IGF1 was repeated and remained elevated at 429ng/mL. Growth hormone suppression test showed nadir of 0.56ng/mL which is higher than <0.3ng/mL expected of high sensitivity GH assays. Pituitary MRI showed three suspected pituitary microadenomas, 4mm and 5mm in left gland, 7mm in right gland. Given difficulty with surgical approach and higher risk of hypopituitarism, she was started on lanreotide for treatment without surgery. She underwent genetic counseling and was offered genetic testing. Conclusion: This case highlights the rare coexistence of acromegaly and adrenal Cushing’s disease in a 50 year old woman. Though the relationship between acromegaly and cancer has been historically controversial, more recent studies have shown an increased risk of both benign and malignant tumors with acromegaly. Untreated Cushing’s Disease has been associated with mildly elevated IGF1 which then decreases after remission; it is unclear if the same pathological process is involved in other etiologies of hypercortisolemia like adrenal Cushing’s syndrome, but re-evaluation of IGF1 after treatment of Cushing’s should be considered. As Cushing’s and acromegaly share similar consequences such as worsening HTN, changing facial appearance, and worsening diabetes, it is prudent to consider each as differential diagnoses when signs do not remit after treatment. Acromegaly has additionally been associated with other endocrinopathies in syndromes including MEN1 syndrome, McCune Albright Syndrome, and Carney Complex. Evaluation for these syndromes and consideration for genetic testing should be considered in the evaluation of a patient with acromegaly and additional associated endocrinopathies. Presentation: Friday, June 16, 2023