RESUMEN
Large-scale epidemiologic studies have consistently demonstrated the effectiveness of mammographic screening programs, however the benefits are still subject to debate. We estimated the effect of the Dutch screening program on breast cancer mortality. In a large multi-region case-referent study, we identified all breast cancer deaths in 2004 and 2005 in women aged 50-75 who had been invited for screening (cases). Cases were individually matched to referents from the population invited to screening. Conditional logistic regression was used to estimate the odds ratio (OR) of breast cancer death according to individual screening history. The OR was adjusted for self-selection bias using regional correction factors for the difference in baseline risk for breast cancer death between screened and unscreened women. A total of 1233 cases and 2090 referents were included in this study. We found a 58% reduction in breast cancer mortality in screened versus unscreened women (adjusted OR = 0.42, 95% CI 0.33-0.53). Screening, i.e. early detection and treatment, has resulted in a substantial reduction in breast cancer mortality, indicating that the Dutch breast cancer screening program is highly effective.
Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/mortalidad , Detección Precoz del Cáncer/mortalidad , Mamografía , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , Persona de Mediana EdadRESUMEN
We retrospectively determined the effect of analogue two-view mammography versus single-view mammography at subsequent screens on breast cancer detection and determined financial consequences for a current digital mammography setting. Two screening radiologists reviewed the mammograms of 536 screen detected cancers (SDCs) and 171 interval cancers (ICs) with single-view mammography (medio-lateral-oblique view) at the last but one screen (SDCs) or latest screen (ICs). They determined whether two-view mammography at the last (but one) screen could have increased the cancer detection rate at that screening round. For subsequent screens, the radiologists also assessed the percentage of SDCs and ICs that had been missed at previous two-view screening mammography (SDC) or latest two-view screening (IC), respectively. Additional personnel and digital storage costs for standard two-view mammography at subsequent screening were calculated for digital screening. Two-view mammography could have facilitated earlier cancer detection in 40.9% (219/536) of SDCs and 39.8% (68/171) of ICs. For two-view screens, 24.4% of SDCs (213/871) were missed at previous two-view screening and 29.3% of ICs (110/375) were missed at the latest screen. Overall costs increase 1.03/screen after implementation of digital two-view mammography. Standard two-view mammography at subsequent screening may modestly increase cancer detection at an earlier stage, whereas additional screening costs are limited.