Genotype and Clinical Phenotype of PPNAD, Carney Complex, and Related Conditions

Primary pigmented nodular adrenocortical disease (PPNAD) is a pituitary-independent, primary adrenal form of hypercortisolism characterized by (a) resistance to suppression by dexamethasone and abolition of the normal diurnal rhythm of cortisol secretion, and (b) distinctive, bilateral, histopathologic changes of the adrenal glands, such as the formation of variably sized, pigmented nodular adenomas, loss of normal zonation and atrophy of the extranodular cortex. PPNAD can be associated with a variety of other manifestations, such as myxomas of the skin, heart, breast and other sites, psammomatous melanotic swannomas involving the peripheral nervous system (PNS), lentigines and blue nevi of the skin and mucosae, growth hormone (GH)-producing adenomas of the pituitary, testicular Sertoli cell tumors, and possibly other neoplasms (adrenocortical and thyroid follicular carcinoma, and ovarian cysts). These associations constitute a distinct clinical syndrome, Carney complex, a genetic syndrome. At present, there are no standardized screening tests for the members of families with affected individuals and the molecular mechanism(s) of this hereditary single and/or multiple neoplasia syndrome have not been completely elucidated (e.g. patients who meet clinical criteria for Carney complex but test negative for PRKAR1A mutation . This study seeks to define the genetic basis of PPNAD and/or Carney complex in sporadic and familial cases and the molecular pathogenesis of their tumors, to identify the carriers of the familial forms of the disease, and to determine the prognosis for carriers and affected individuals. The methods include standard clinical testing for endocrine and nonendocrine pathologic conditions of the subjects of the study, linkage analysis with DNA markers from areas of the genome likely to harbor the responsible gene(s), and finally genetic screening of these genes. Molecular studies of the tumors of the patients will provide additional clues for the pathophysiologic mechanisms leading to PPNAD/Carney complex. The study will ultimately provide sufficient data for genetic counseling of families with PPNAD and/or Carney complex, and, ultimately, the means for genetic screening and prenatal testing.