Comparison of screening mammography in the United States and the United kingdom.
BACKGROUND
Screening mammography differs between the United States and the United Kingdom; a direct comparison may suggest methods to improve the practice.


OBJECTIVE
To compare screening mammography performance between the United States and the United Kingdom among similar-aged women.


METHODS
Women aged 50 years or older were identified who underwent 5.5 million mammograms from January 1, 1996, to December 31, 1999, within 3 large-scale mammography registries or screening programs: the Breast Cancer Surveillance Consortium (BCSC, n = 978 591) and National Breast and Cervical Cancer Early Detection Program (NBCCEDP, n = 613 388) in the United States; and the National Health Service Breast Screening Program (NHSBSP, n = 3.94 million) in the United Kingdom. A total of 27 612 women were diagnosed with breast cancer (invasive or ductal carcinoma in situ) within 12 months of screening among the 3 groups.


METHODS
Recall rates (recommendation for further evaluation including diagnostic imaging, ultrasound, clinical examination, or biopsy) and cancer detection rates were calculated for first and subsequent mammograms, and within 5-year age groups.


RESULTS
Recall rates were approximately twice as high in the United States than in the United Kingdom for all age groups; however, cancer rates were similar. Among women aged 50 to 54 years who underwent a first screening mammogram, 14.4% in the BCSC and 12.5% in the NBCCEDP were recalled for further evaluation vs only 7.6% in the NHSBSP. Cancer detection rates per 1000 mammogram screens were 5.8, 5.9, and 6.3, in the BCSC, NBCCEDP, and NHSBSP, respectively. Recall rates were lower for subsequent examinations in all 3 settings but remained twice as high in the United States. A similar percentage of women underwent biopsy in each setting, but rates of percutaneous biopsy were lower and open surgical biopsy higher in the United States. Open surgical biopsies not resulting in a diagnosis of cancer (negative biopsies) were twice as high in the United States than in the United Kingdom. Based on a 10-year period of screening 1000 women aged 50 to 59 years, 477, 433, and 175 women in the BCSC, NBCCEDP, and NHSBSP, respectively, would be recalled; and for women aged 60 to 69 years, 396, 334, and 133 women, respectively. The estimated cancer detection rates per 1000 women aged 50 to 59 years were 24.5, 23.8, and 19.4, respectively, and for women aged 60 to 69 years, 31.5, 26.6, and 27.9, respectively.


CONCLUSIONS
Recall and negative open surgical biopsy rates are twice as high in US settings than in the United Kingdom but cancer detection rates are similar. Efforts to improve US mammographic screening should target lowering the recall rate without reducing the cancer detection rate.
Department of Radiology, University of California, San Francisco 94115, USA. rebecca.smith-bindman@radiology.ucsf.edu
Rebecca
R
Smith-Bindman
Philip W
PW
Chu
Diana L
DL
Miglioretti
Edward A
EA
Sickles
Roger
R
Blanks
Rachel
R
Ballard-Barbash
Janet K
JK
Bobo
Nancy C
NC
Lee
Matthew G
MG
Wallis
Julietta
J
Patnick
Karla
K
Kerlikowske
D000368:Aged; D001706:Biopsy / Q000706:statistics & numerical data; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008327:Mammography / Q000706:statistics & numerical data*; D008403:Mass Screening / Q000706:statistics & numerical data*; D008875:Middle Aged; D006113:United Kingdom / Q000453:epidemiology; D014481:United States / Q000453:epidemiology