Natural history of the benign breast lump.

A prospective study of 112 patients with clinically discrete benign breast lumps has shown that 68 per cent of patients experienced resolution of their lumps over a period of up to 2 years. Resolution of both fibro-adenomas and discrete areas of fibro-adenosis was observed. Diagnosis was achieved by clinical examination and fine needle aspiration cytology. Four patients thought clinically to have benign disease were proven by cytology to have a carcinoma, but no patient with a cytopathological diagnosis of benign disease has developed cancer during or subsequent to this study. We recommend that patients under 35 years of age with clinically and cytologically benign breast lumps can be offered the option of non-excision in the reasonable expectation of resolution of their lesion.