exogenous estrogens lowered the observed breast cancer risk in women with atypical hyperplasia ( rr = 3.0 versus 4.5 ) , proliferative disease without atypia ( rr = 0.92 versus 1.9 ) , and in women without proliferative disease ( rr = 0.69 versus 0.91 ) .
C0333977
atypical hyperplasia
C0741302
atypia