Effect of screening and adjuvant therapy on mortality from breast cancer.
BACKGROUND
We used modeling techniques to assess the relative and absolute contributions of screening mammography and adjuvant treatment to the reduction in breast-cancer mortality in the United States from 1975 to 2000.


METHODS
A consortium of investigators developed seven independent statistical models of breast-cancer incidence and mortality. All seven groups used the same sources to obtain data on the use of screening mammography, adjuvant treatment, and benefits of treatment with respect to the rate of death from breast cancer.


RESULTS
The proportion of the total reduction in the rate of death from breast cancer attributed to screening varied in the seven models from 28 to 65 percent (median, 46 percent), with adjuvant treatment contributing the rest. The variability across models in the absolute contribution of screening was larger than it was for treatment, reflecting the greater uncertainty associated with estimating the benefit of screening.


CONCLUSIONS
Seven statistical models showed that both screening mammography and treatment have helped reduce the rate of death from breast cancer in the United States.
Berry
Donald A
DA
Department of Biostatistics and Applied Mathematics, M.D. Anderson Cancer Center, Houston, TX 77030, USA. dberry@mdanderson.org
Cronin
Kathleen A
KA
Plevritis
Sylvia K
SK
Fryback
Dennis G
DG
Clarke
Lauren
L
Zelen
Marvin
M
Mandelblatt
Jeanne S
JS
Yakovlev
Andrei Y
AY
Habbema
J Dik F
JD
Feuer
Eric J
EJ
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000401:mortality*; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D015994:Incidence; D008327:Mammography / Q000706:statistics & numerical data; D008403:Mass Screening; D008875:Middle Aged; D015233:Models, Statistical; D009367:Neoplasm Staging; D018426:SEER Program; D016019:Survival Analysis; D013629:Tamoxifen / Q000627:therapeutic use; D014481:United States / Q000453:epidemiology
D000970:Antineoplastic Agents; D013629:Tamoxifen