Multiple peripheral lung cysts and hemoptysis in an otherwise asymptomatic adult.

In this report we describe a young adult man who developed multiple, thin-walled cystic lesions of the lungs on chest roentgenograms over a 2-yr period and whose only symptom was infrequent hemoptysis. There were no objective findings of pulmonary infection. Microscopic examination of one of the lesions showed the histologic features of a lung cyst. The cyst wall contained numerous ectatic vascular channels and disordered growth of vascular elements, findings not previously described in association with peripheral lung cysts. The presence of both endodermal and mesodermal derivatives contributing to the composition of the lesions raises the possibility that these represent hamartomatous malformations.