Haemangioleiomyomatous tumour of the lung.

A case of haemangioleiomyomatous tumour of the lung, occurring as a peripheral, solitary nodule in an asymptomatic 54-year-old man is presented. The tumour was well-demarcated and microscopically it was characterised by the presence of vascular spaces with endothelial, pericytic, and, predominantly, smooth muscle proliferation. Islands of cartilage and slit-like spaces lined by bronchial epithelium make this a hamartomatous lesion of a quite distinctive and unusual variety, which does not fit any of the well-recognised patterns of hamartomas previously described. The long-term prognosis after limited excision is considered to be favourable.