Introduction Carney Complex (CNC) is a rare multiple endocrine and nonendocrine neoplasia syndrome. Manifestations and genotype-phenotype correlations have been described by retrospective studies, but no prospective study evaluating the occurrence of the different manifestations has been available so far. Methods This multicenter national prospective study included patients with CNC, primary pigmented nodular adrenal disease (PPNAD), or a pathogenic PRKAR1A mutation; after a full initial workup, participants were followed for 3 years with annual standardized evaluation. Results The cohort included 70 patients (50 female/20 male, mean age 35.4 ± 16.7 years, 81% carrying PRKAR1A mutation). The initial investigations allowed identification of several manifestations. At the end of the 3-year follow-up, the newly diagnosed manifestations of the disease were subclinical acromegaly in 6 patients, bilateral testicular calcifications in 1 patient, and cardiac myxomas in 2 patients. Recurrences of cardiac myxomas were diagnosed in 4 patients during the 3-year follow-up study period. Asymptomatic abnormalities of the corticotroph and somatotroph axis that did not meet criteria of PPNAD and acromegaly were observed in 11.4% and 30% of the patients, respectively. Patients carrying the PRKAR1A c.709-7del6 mutation had a mild phenotype. Conclusion This study underlines the importance of a systematic follow-up of the CNC manifestations, especially a biannual screening for cardiac myxoma. By contrast, regular screening for the other manifestations after a first extensive workup could be spread out, leading to a lighter and more acceptable follow-up schedule for patients. These are important results for recommendations for long-term management of CNC patients.

This review reports the main molecular alterations leading to development of benign cortisol and/or aldosterone secreting adrenal tumors. Causes of adrenal Cushing can be divided in two groups: multiple bilateral tumors or adenomas secreting cortisol. Bilateral causes are mainly Primary Pigmented Nodular Adrenocortical Disease (PPNAD), most of the time due to PRKAR1A germline inactivating mutations, and Primary Bilateral Macronodular Adrenal Hyperplasia (PBMAH), that can be caused in some rare syndromic cases by germline inactivating mutations of MEN1, APC and FH and of ARMC5 in isolated forms. PRKACA somatic activating mutations are the main alterations in unilateral cortisol producing adenomas (CPA). In primary hyperaldosteronism (PA), familial forms were identified in 1-5% of cases: familial hyperaldosteronism type I (FH-I) due to a chimeric CYP11B1/CYP11B2 hybrid gene, FH-II due to CLCN-2 germline mutations, FH-III due to KCNJ5 germline mutations, FH-IV due to CACNA1H germline mutations and PA, seizures and neurological abnormalities (PASNA) syndrome due to CACNA1D germline mutations. Several somatic mutations have been found in aldosterone producting adenomas (APAs) in KCNJ5, ATP1A1, ATP2B3, CACNA1D and CTNNB1 genes.