Case for conservative management of selected fibro-adenomas of the breast.

To assess the safety of a conservative approach to fibro-adenoma of the breast we prospectively studied 321 women with this clinical diagnosis, and performed aspiration cytology and excision biopsy. There was histological confirmation of fibro-adenoma in 217 (68 per cent), the remainder having various benign conditions and 4 (1.3 per cent) had carcinoma. Aspiration cytology had a sensitivity of 87 per cent and a specificity of 76 per cent for fibro-adenoma. Three cases of carcinoma were identified cytologically and the fourth was regarded as suspicious. To estimate the risk of missing carcinoma we compared the annual frequency of carcinoma with fibro-adenoma in young women and found a ratio of 1:470 between 15 and 19 years, 1:133 between 20 and 24 years and 1:9 in the 25-29 age group. To assess patients' views on non-operative treatment of benign breast masses we asked 124 women, 10 days postoperatively, whether they preferred a conservative approach for a cytologically benign lump: 26 (21 per cent) opted for conservative management in the future and 8 (7 per cent) would have preferred conservatism rather than their recent excision. A conservative approach is safe for clinically and cytologically benign breast lumps in women under 25 years, but very few will accept it.