Use of tamoxifen in advanced male breast cancer.

Tamoxifen citrate has been administered continuously at various dosages to 31 males with evaluable advanced breast cancer in 16 different centers. There were 15 complete or partial responders (48%) and five patients who were assessed to have achieved disease stabilization. In this series, there were responses in visceral-dominant (five of ten), bone-dominant (two of five), and soft tissue-dominant (eight of 15) disease. Response to tamoxifen appeared to be related to estrogen receptor status and to response to prior or subsequent endocrine therapy, although no firm conclusions can be drawn from such small numbers.