Mammography screening matters for young women with breast carcinoma: evidence of downstaging among 42-49-year-old women with a history of previous mammography screening.

BACKGROUND: Breast carcinoma is the leading cause of death for women between the ages of 40 and 49 years, yet questions linger regarding the effectiveness of screening mammography in reducing mortality rates among women of this age. In the current study, the authors report on the association between cancer stage at diagnosis and a history of mammography screening in a clinical setting that has emphasized informed choice regarding mammography screening for women in this age group.
METHODS: Previous mammographic screening for 247 breast cancer patients 42-49 years of age who were diagnosed at Kaiser Permanente Colorado during 1994-2000 was evaluated relative to cancer stage. Cancer stage was dichotomized into early (American Joint Committee on Cancer [AJCC] Stages 0 and I) and late (AJCC Stages II-IV) and previous screening was defined as at least one normal screening mammogram within 24 months before the breast carcinoma diagnosis.
RESULTS: Women who were screened were less likely to be diagnosed at a late stage than were women who were not screened (40% vs. 52% late stage, respectively). Adjusted for age, year of diagnosis, and family history, screened women were 0.56 (95% confidence interval = 0.32-0.97) times as likely as unscreened women to be diagnosed at a late stage.
CONCLUSIONS: Women 42-49 of years with breast carcinoma who undergo regular screening mammography have a more favorable cancer stage than do women with breast carcinoma who do not undergo regular screening. This downstaging of breast carcinoma is likely to translate into improved breast carcinoma survival resulting from screening mammography for women 40-49 years of age. Copyright 2003 American Cancer Society