Three's company: A woman with rash, uterine mass and cystic lungs

Cystic lung disease encompasses a wide variety of clinical entities, the diagnosis of which is sometimes straightforward and other times obscure.  To narrow the list of possibilities, it behooves the physician to consider the context in which the cystic lung disease is uncovered. Clues to the diagnosis might be provided by findings that are not initially obvious and are not located in the thorax. We describe an instructive case of a woman with cystic lungs detected during a search for malignancy prompted by a diagnosis of dermatomyositis. Malignancy was indeed uncovered in the form of endometrial carcinoma, the management of which eventually also established the etiology of cystic lung disease. In the discussion we attempt to connect the patient's autoimmune disease, uterine cancer, and lung cysts. The potential interplay among these three components of her presentation makes for intriguing mechanistic speculation.