FRI267 Carney Complex From A Single Familycarney Complex From A Single Family Followed Up Over 20 Years With Different Clinical Pattern Evolution

Abstract Disclosure: A.W. Kuhn: None. D.S. de Melo: None. H.L. Charchar: None. B.M. Mariani: None. M.Y. Nishi: None. F.L. Ledesma: None. F.Y. Tanno: None. V. Srougi: None. J.L. Chambo: None. A. Latronico: None. B.B. Mendonca: None. M.Q. Almeida: None. M.C. Fragoso: None. Background: Carney complex (CNC) is a hereditary syndrome with autosomal dominant inheritance, composed of multiple neoplasms, such as benign and malignant, endocrine and nonendocrine tumors (cardiac, cutaneous and neural). The primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of Cushing syndrome is the most common endocrine neoplasia in CNC. The most frequent genetic cause is related with the presence of germline pathogenic allelic variants on PRKAR1A. Overall CNC penetrance among carriers of the PRKAR1A allelic variant is approximately 97.5%, however, families with long-term follow up is rarely described in literature. Clinical Case: A 17-year-old male, was referred to our Hospital in 2003 due to weight gain (≈10 Kg), BMI 27.27 Kg/m2, acne, occurrence of abdomen purplish striae (>1cm), facial plethora and arrest of pubertal development for last 2 years. He has had pigmented facial lesions since 9 years old. Laboratory revealed suppressed ACTH <18.0 pg/mL, failure to suppress cortisol levels after low dose dexamethasone test (DST-1mg): cortisol 29 µg/dL (normal range: <1.8 µg/dL), and total urinary cortisol (TUC), 2809 µg/24 h (normal range: 30-300 µg/24h). Abdominal CT scan showed normal right adrenal gland and a micronodule (0.8 cm) in the left adrenal gland. Bone densitometry showed an important loss of density. Owing to ACTH-independent Cushing's syndrome and adrenal with micronodule, the most plausible diagnostic hypothesis was PPNAD associated to CNC. He underwent bilateral laparoscopic adrenalectomy and the histological data confirmed PPNAD on both adrenal glands. He developed primary adrenal insufficiency and he maintains continuous replacement with gluco and mineralocorticoids. The genetic analysis identified a heterozygous germline nonsense pathogenic variant on PRKAR1A (p.Tyr21X) in exon 2. His relatives, such as father, two younger sisters, one paternal aunt and a female cousin carried the same nonsense variant. All of them also presented facial lentiginous but without Cushing features. In the first investigation, all his relatives showed possible autonomous cortisol secretion. In follow-up of almost 20 years, the index case and his family members did not develop other manifestations of CNC. Only his father developed metabolic syndrome, but all relatives maintained subclinical hypercortisolism due to possible autonomous cortisol secretion without any clinical repercussions. Clinical Lessons: Carney complex is a rare disease and the follow-up of familial cases over the years can show different clinical pattern despite the same germline pathogenic variant. Probably somatic molecular mechanisms as modulators could trigger specifically clinical manifestations. Presentation: Friday, June 16, 2023