A new study published in October of 2015 compared the proportion of breast cancers with less vs. more favorable prognostic characteristics in women screening annually vs. biennially by age, menopausal status, and postmenopausal hormone therapy (HT) use. Using a log-binomial regression to model the proportion of breast cancers with less favorable characteristics following a biennial vs. annual screen by 10-year age groups and by menopausal status and current postmenopausal HT use, researchers found that premenopausal women diagnosed as having breast cancer following biennial vs. annual screening mammography were more likely to have tumors with less favorable prognostic characteristics. Also, postmenopausal women not using HT who were diagnosed as having breast cancer following a biennial or annual screen were found to have similar proportions of tumors with less favorable prognostic characteristics.
To read more, see the following article on the JAMA Oncology website: Breast Tumor Prognostic Characteristics and Biennial vs. Annual Mammography, Age, and Menopausal Status