Ductal carcinoma in situ in a 27-year-old woman with McCune-Albright syndrome.

McCune-Albright syndrome (MAS) is a sporadic disorder characterized by the triad of irregularly edged hyperpigmented macules (café au lait spots); a slowly progressive bone disorder, polyostotic fibrous dysplasia, usually involving the base of the skull and the long bones; and luteinizing hormone-releasing hormone (LHRH)-independent precocious puberty. This case is the first report of a 27-year-old woman with ductal carcinoma in situ (DCIS) and Paget's disease of the nipple associated with MAS. The discussion focuses on two endocrine manifestations of this syndrome including precocious puberty and excess growth hormone secretion. In our patient, both her early puberty and pituitary adenoma, in association with MAS, resulted in excess production and secretion of estrogen and growth hormone. Both of these hormones function to stimulate breast growth and development. We hypothesize they are responsible for this patient's DCIS and Paget's disease of the nipple so early in life.