For example , mammography screening does not seem to create anxiety in women who are given a clear result after a mammogram .
The incidence of breast cancer and mortality increases with age , and the GDG extrapolated that the absolute health benefits are greater in women aged 45 to 49 than those aged 40 to 44 years .
However , for the 45- to 49-year age group , the higher breast cancer incidence and mortality compared with women between the ages of 40 and 44 , as well as observational evidence showing a greater benefit in this age group ( 33 ) , led the GDG to judge that the balance of health effects probably favors screening , although the required re sources for screening likely differ across setting s ( 34 , 35 ) .
Other EtD criteria also were generally in favor of implementing organized mammography screening in this age group .
Despite intensified efforts by the European Council since 2003 , the implementation of organized , population -based mammography screening is not uniform across Europe and depends greatly on the policies in place in different countries , the organization of health care , and available re sources ( 1 ) .
Since the last edition of the European Guidelines on Breast Cancer Screening and Diagnosis was published in 2006 ( 2 ) , new evidence regarding breast cancer and innovation in guideline methodology prompted the European Commission Initiative on Breast Cancer ( ECIBC ) to develop new evidence -based recommendations ( in short , the European Breast Guidelines ) .
These guidelines inform women , health professionals , and policymakers about important questions related to organized mammography screening and breast cancer diagnosis , but recommendations may apply in context s in which organized screening programs are not in place .
Women generally consider these undesirable effects acceptable ( low certainty of evidence ) , and a systematic review suggested that women place a relatively low value on the psychosocial and physical effects of false-positive results and overdiagnosis ; however , some studies raised concerns about whether women fully underst and the result ing implication s ( 15 ) .
How Often Should Women Attend an Organized Mammography Screening Program ?
Breast Tumor Prognostic Characteristics and Biennial vs Annual Mammography, Age, and Menopausal Status.
IMPORTANCE Screening mammography intervals remain under debate in the United States . OBJECTIVE To compare 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 . DESIGN , SETTING , AND PARTICIPANTS This was a study of a prospect i ve cohort from 1996 to 2012 at Breast Cancer Surveillance Consortium facilities . A total of 15,440 women ages 40 to 85 years with breast cancer diagnosed within 1 year of an annual or within 2 years of a biennial screening mammogram .  EXPOSURES We up date d previous analyses by using narrower intervals for defining annual ( 11 - 14 months ) and biennial ( 23 - 26 months ) screening . MAIN OUTCOMES AND MEASURES We defined less favorable prognostic characteristics as tumors that were stage IIB or higher , size greater than 15 mm , positive nodes , and any 1 or more of these characteristics . We used 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 . RESULTS Among 15,440 women with breast cancer , most were 50 years or older ( 13,182 [ 85.4 % ] ) , white ( 12,063 [ 78.1 % ] ) , and postmenopausal ( 9823 [ 63.6 % ] ) . Among 2027 premenopausal women ( 13.1 % ) , biennial screeners had higher proportions of tumors that were stage IIB or higher ( relative risk [ RR ] , 1.28 [ 95 % CI , 1.01 - 1.63 ] ; P=.04 ) , size greater than 15 mm ( RR , 1.21 [ 95 % CI , 1.07 - 1.37 ] ; P=.002 ) , and with any less favorable prognostic characteristic ( RR , 1.11 [ 95 % CI , 1.00 - 1.22 ] ; P=.047 ) compared with annual screeners . Among women currently taking postmenopausal HT , biennial screeners tended to have tumors with less favorable prognostic characteristics compared with annual screeners ; however , 95 % CIs were wide , and differences were not statistically significant ( for stage 2B+ , RR , 1.14 [ 95 % CI , 0.89 - 1.47 ] , P=.29 ; size>15 mm , RR , 1.13 [ 95 % CI , 0.98 - 1.31 ] , P=.09 ; node positive , RR , 1.18 [ 95 % CI , 0.98 - 1.42 ] , P=.09 ; any less favorable characteristic , RR , 1.12 [ 95 % CI , 1.00 - 1.25 ] , P=.053 ) . The proportions of tumors with less favorable prognostic characteristics were not significantly larger for biennial vs annual screeners among postmenopausal women not taking HT  ( eg , any characteristic : RR , 1.03 [ 95 % CI , 0.95 - 1.12 ] ; P=.45 ) , postmenopausal HT users after subdividing by type of hormone use ( eg , any characteristic : estrogen+progestogen users , RR , 1.16 [ 95 % CI , 0.91 - 1.47 ] ; P=.22 ; estrogen-only users , RR , 1.14 [ 95 % CI , 0.94 - 1.37 ] ; P=.18 ) , or any 10-year age group ( eg , any characteristic : ages 40 - 49 years , RR , .1.04 [ 95 % CI , 0.94 - 1.14 ] ; P=.48 ; ages 50 - 59 years , RR , 1.03 [ 95 % CI , 0.94 - 1.12 ] ; P=.58 ; ages 60 - 69 years , RR , 1.07 [ 95 % CI , 0.97 - 1.19 ] ; P=.18 ; ages 70 - 85 years , RR , 1.05 [ 95 % CI , 0.94 - 1.18 ] ; P=.35 ) . CONCLUSIONS AND RELEVANCE Premenopausal women diagnosed as having breast cancer following biennial vs annual screening mammography are more likely to have tumors with less favorable prognostic characteristics . Postmenopausal women not using HT who are diagnosed as having breast cancer following a biennial or annual screen have similar proportions of tumors with less favorable prognostic characteristics
For example , mammography screening does not seem to create anxiety in women who are given a clear result after a mammogram .
The incidence of breast cancer and mortality increases with age , and the GDG extrapolated that the absolute health benefits are greater in women aged 45 to 49 than those aged 40 to 44 years .
However , for the 45- to 49-year age group , the higher breast cancer incidence and mortality compared with women between the ages of 40 and 44 , as well as observational evidence showing a greater benefit in this age group ( 33 ) , led the GDG to judge that the balance of health effects probably favors screening , although the required re sources for screening likely differ across setting s ( 34 , 35 ) .
Other EtD criteria also were generally in favor of implementing organized mammography screening in this age group .
Despite intensified efforts by the European Council since 2003 , the implementation of organized , population -based mammography screening is not uniform across Europe and depends greatly on the policies in place in different countries , the organization of health care , and available re sources ( 1 ) .
Since the last edition of the European Guidelines on Breast Cancer Screening and Diagnosis was published in 2006 ( 2 ) , new evidence regarding breast cancer and innovation in guideline methodology prompted the European Commission Initiative on Breast Cancer ( ECIBC ) to develop new evidence -based recommendations ( in short , the European Breast Guidelines ) .
These guidelines inform women , health professionals , and policymakers about important questions related to organized mammography screening and breast cancer diagnosis , but recommendations may apply in context s in which organized screening programs are not in place .
Women generally consider these undesirable effects acceptable ( low certainty of evidence ) , and a systematic review suggested that women place a relatively low value on the psychosocial and physical effects of false-positive results and overdiagnosis ; however , some studies raised concerns about whether women fully underst and the result ing implication s ( 15 ) .
How Often Should Women Attend an Organized Mammography Screening Program ?