The effect of danazol on discrete benign breast lumps

Surgical biopsy of benign breast lumps produces a significant surgical workload, morbidity and cost. A double-blind placebo-controlled trial of danazol 200 mg daily was carried out with the aim of reducing the size of solid discrete breast lumps, thereby avoiding surgical biopsy in benign cases. Twenty-two women with lumps diagnosed as benign by clinical examination, mammography and cytology were randomized to take danazol and 26 placebo. The patients were assessed monthly by two clinicians until surgical biopsy. Twenty patients in each treatment group were evaluated and five patients discontinued treatment (two on danazol, three on placebo) and three (all on placebo) were found to be malignant. There was no difference in the number of lumps which responded to treatment with danazol or placebo. There was a reduction in the number of lumps which subsequently developed in the breasts treated with danazol during the 12-month follow-up period, but this failed to achieve statistical significance. Danazol does not promote resolution of solid discrete benign breast lumps. Careful selection of women over 25 years for surgery with solid discrete breast lumps is required, utilizing a dedicated breast cytologist with a multidisciplinary approach, to avoid missing breast cancers.