Risk of breast cancer after false-positive test results in screening mammography

TY - JOUR

T1 - Risk of breast cancer after false-positive test results in screening mammography

AU - von Euler-Chelpin, My Catarina

AU - Risør, Louise Madeleine

AU - Thorsted, Brian Larsen

AU - Vejborg, Ilse

PY - 2012/5/2

Y1 - 2012/5/2

N2 - Background: Screening for disease in healthy people inevitably leads to some false-positive tests in disease-free individuals. Normally, women with false-positive screening tests for breast cancer are referred back to routine screening. However, the long-term outcome for women with false-positive tests is unknown. Methods: We used data from a long-standing population-based screening mammography program in Copenhagen, Denmark, to determine the long-term risk of breast cancer in women with false-positive tests. The age-adjusted relative risk (RR) of breast cancer for women with a false-positive test compared with women with only negative tests was estimated with Poisson regression, adjusted for age, and stratified by screening round and technology period. All statistical tests were two-sided. Results: A total of 58 003 women, aged 50-69 years, were included in the analysis. Women with negative tests had an absolute cancer rate of 339/100 000 person-years at risk, whereas women with a false-positive test had an absolute rate of 583/100 000 person-years at risk. The adjusted relative risk of breast cancer after a false-positive test was 1.67 (95% confidence interval [CI] 1.45 to 1.88). The relative risk remained statistically significantly increased 6 or more years after the false-positive test, with point estimates varying between 1.58 and 2.30. When stratified by assessment technology phase and using equal follow-up time, the false-positive group from the mid 1990s had a statistically significantly higher risk of breast cancer (RR = 1.65, 95% CI = 1.22 to 2.24) than the group with negative tests, whereas the false-positive group from the early 2000s was not statistically significantly different from the group testing negative. Conclusions: The implementation of new assessment technology coincided with a decrease in the size of excess risk of breast cancer for women with false-positive screening results. However, it may be beneficial to actively encourage women with false-positive tests to continue to attend regular screening.

AB - Background: Screening for disease in healthy people inevitably leads to some false-positive tests in disease-free individuals. Normally, women with false-positive screening tests for breast cancer are referred back to routine screening. However, the long-term outcome for women with false-positive tests is unknown. Methods: We used data from a long-standing population-based screening mammography program in Copenhagen, Denmark, to determine the long-term risk of breast cancer in women with false-positive tests. The age-adjusted relative risk (RR) of breast cancer for women with a false-positive test compared with women with only negative tests was estimated with Poisson regression, adjusted for age, and stratified by screening round and technology period. All statistical tests were two-sided. Results: A total of 58 003 women, aged 50-69 years, were included in the analysis. Women with negative tests had an absolute cancer rate of 339/100 000 person-years at risk, whereas women with a false-positive test had an absolute rate of 583/100 000 person-years at risk. The adjusted relative risk of breast cancer after a false-positive test was 1.67 (95% confidence interval [CI] 1.45 to 1.88). The relative risk remained statistically significantly increased 6 or more years after the false-positive test, with point estimates varying between 1.58 and 2.30. When stratified by assessment technology phase and using equal follow-up time, the false-positive group from the mid 1990s had a statistically significantly higher risk of breast cancer (RR = 1.65, 95% CI = 1.22 to 2.24) than the group with negative tests, whereas the false-positive group from the early 2000s was not statistically significantly different from the group testing negative. Conclusions: The implementation of new assessment technology coincided with a decrease in the size of excess risk of breast cancer for women with false-positive screening results. However, it may be beneficial to actively encourage women with false-positive tests to continue to attend regular screening.

KW - Age Distribution

KW - Age Factors

KW - Aged

KW - Aged, 80 and over

KW - Breast Neoplasms

KW - Denmark

KW - Early Detection of Cancer

KW - False Positive Reactions

KW - Female

KW - Humans

KW - Incidence

KW - Mammography

KW - Middle Aged

KW - Time Factors

U2 - 10.1093/jnci/djs176

DO - 10.1093/jnci/djs176

M3 - Journal article

C2 - 22491228

SN - 1460-2105

VL - 104

SP - 682

EP - 689

JO - National Cancer Institute. Journal (Online)

JF - National Cancer Institute. Journal (Online)

IS - 9

ER -