For the past year we have studied a young woman with a unique triad of findings: enormous breast hypertrophy, generalized melanoderma, and, finally, thousands of pruritic polycylic bands undergoing continuous migration over the skin surface. We have encountered nothing of this kind in our clinical experience or in the literature. Intensive investigative studies disclosed the presence of an autoallergic state. The patient proved to have specific circulating autoantibodies to her own cystic breast tissue. In addition, her serum showed a strongly positive L.E. phenomenon. Accordingly it is our wish to record and to attempt to interpret these clinical observations and laboratory studies. Report of a Case The patient, a 26-year-old white woman, was first seen by us in October, 1958.* At that time she presented the three problems (Figs. 1, 2, 3) of breast enlargement, melanoderma, and gyrate migratory bands. Although she had had purpura and an attack of poison