Idiopathic gynecomastia, unilateral or bilateral, is a common physical find
ing in normal men. Successful treatment using tamoxifen (antiestrogen) and
danazol (antiandrogen) has recently been reported. We compared the efficacy
of tamoxifen and danazol in the treatment of idiopathic gynecomastia. We r
eviewed the clinical records of patients with idiopathic gynecomastia prese
nting to the Department of Surgery, University of Hong Kong, between August
1990 and September 1995. Medical treatment with either tamoxifen (20 mg/d)
or danazol (400 mg/d) was offered and continued until a static response wa
s achieved. The treatment response was compared. Sixty-eight patients with
idiopathic gynecomastia were seen in the Breast Clinic. The median age was
39.5 years (range, 13-82), with a median duration of symptoms of 3 months (
range, 1-90). The median size was 3 cm (range, 1-7). Twenty-three patients
were treated with tamoxifen ansi 20 with danazol. Complete resolution of th
e gynecomastia was recorded in 18 patients (78.2%) treated with tamoxifen,
whereas only 8 patients (40%) in the danazol group had complete resolution.
Five patients, all from the tamoxifen group, developed recurrence of breas
t mass. In conclusion, hormonal manipulation is effective in the treatment
of patients with idiopathic gynecomastia. Although the effect is more marke
d for tamoxifen compared with danazol, the relapse rate is higher for tamox
ifen. Further prospective randomized studies would be useful in defining th
e role of these drugs in the management of patients with idiopathic gynecom
astia.