Impact of Mammography Detection on the Course of Breast Cancer in Women Aged 40–49 Years
Menée sur 1 997 femmes âgées de 40 à 49 ans et ayant été diagnostiquées avec un cancer du sein entre 1990 et 2008, cette étude analyse l'évolution des méthodes de détection du cancer et évalue notamment l'effet de la mammographie sur le stade au diagnostic
Purpose: To analyze trends in detection method related to breast cancer stage at diagnosis, treatments, and outcomes over time among 40–49-year-old women.Materials and Methods: i This study was institutional review board approved, with a waiver of informed consent, and HIPAA compliant. A longitudinal prospective cohort study was conducted of women aged 40–49 years who had primary breast cancer, during 1990–2008, and were identified and tracked by a dedicated registry database (n = 1977). Method of detection—patient detected (PtD), physician detected (PhysD), or mammography detected (MamD)—was chart abstracted. Disease-specific survival and relapse-free survival statistics were calculated by using the Kaplan-Meier method for stage I–IV breast cancer.Results: A significant increase in the percentage of MamD breast cancer over time (28%–58%) and a concurrent decline in patient and physician detected (Pt/PhysD) breast cancer (73%–42%) (Pearson x2 = 72.72, P < .001) were observed over time from 1990 to 2008, with an overall increase in lower-stage disease detection and a decrease in higher-stage disease. MamD breast cancer patients were more likely to undergo lumpectomy (67% vs 48% of Pt/PhysD breast cancer patients) and less likely to undergo modified radical mastectomy (25% vs 47% of the Pt/PhysD breast cancer patients) (P < .001). Uncorrected for stage, 13% of MamD breast cancer patients underwent surgery and chemotherapy versus 22% of Pt/PhysD breast cancer patients (P < .001), and 31% of MamD breast cancer patients underwent surgery, radiation therapy, and chemotherapy versus 59% of Pt/PhysD breast cancer patients (x2 = 305.13, P < .001). Analyzing invasive cancers only, 5-year relapse-free survival for MamD breast cancer patients was 92% versus 88% for Pt/PhysD patients (log-rank test, 12.47; P < .001).Conclusion: Increased mammography-detected breast cancer over time coincided with lower–stage disease detection resulting in reduced treatment and lower rates of recurrence, adding factors to consider when evaluating the benefits of mammography screening of women aged 40–49 years.© RSNA, 2012Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11111734/-/DC1
Radiology , résumé, 2012