Digitized assessment of mammographic breast density--effects of continuous combined hormone therapy, tibolone and black cohosh compared to placebo.

Abstract Objectives To determine the effects of continuous combined hormone therapy, tibolone, black cohosh, and placebo on digitized mammographic breast density in postmenopausal women. Study design A prospective, double-blind, placebo-controlled study of 154 postmenopausal women randomized to estradiol 2 mg/norethisterone acetate 1 mg (E2/NETA), tibolone 2.5 mg or placebo and a prospective, open, uncontrolled drug safety study, of which 65 postmenopausal women were treated with black cohosh. Mammograms, at baseline and after six months of treatment, were previously classified according to visual quantification scales. Main outcome measures Reanalysis of assessable mammograms by digitized quantification of breast density. Results Treatment groups were comparable at baseline. During treatment, both E2/NETA and tibolone significantly increased breast density (mean increase 14.3%, p p p Conclusions Digitized mammographic breast density is a highly sensitive method confirming significant increase in density by standard E2/NETA treatment and to a lesser extent by tibolone, whereas black cohosh does not influence mammographic breast density during six months treatment. Digitized assessment also yields data on individual variation and small increases left undetectable by visual classification.