Breast cancer in women who undergo screening mammography: relationship of hormone replacement therapy to stage and detection method.

PURPOSE To compare the breast cancer stages and detection methods in screened women who receive hormone replacement therapy (HRT) with those in screened women who do not receive HRT to determine whether HRT affects the stage or mammographic detection of malignancy. MATERIALS AND METHODS One hundred fifteen cases of breast cancer in women (age range, 55-65 years) in whom at least one screening mammogram had been obtained at least 24 months before diagnosis and in whom the history regarding HRT could be determined were reviewed retrospectively. Statistical analysis was performed with CHI-2 analysis and the Fischer exact test. RESULTS The cancer stages in the 58 women who received HRT were stage 0 in 15 (26%), stage I in 28 (48%), stage II in 13 (22%), and stage III in two (3%) women. The stages in the 57 women who did not receive HRT were stage 0 in 19 (33%), stage I in 24 (42%), stage II in 11 (19%), stage III in two (4%), and stage IV in one (2%) woman. Cancers in 38 (67%) of the women who did not receive HRT and in 38 (66%) of those who did receive HRT were detected with mammography alone; false-negative mammograms were obtained in five (9%) women in the non-HRT group and in four (7%) women in the HRT group (P = .89). CONCLUSION Among screened women who developed breast cancer, there were no significant differences in cancer stages or in the number of mammographically detected cancers or false-negative mammograms between the HRT group and the non-HRT group.