Objective: Population-wide mammographic screening programs aim to reduce breast cancer mortality. However, a broad view of the harms and benefits of these programs is necessary to favor informed decisions, especially in the earliest stages of the disease. Here, we compare the outcomes of patients diagnosed with breast ductal carcinoma in situ in participants and non-participants of a population-based mammographic screening program. Methods: A retrospective cohort study of all patients diagnosed with breast ductal carcinoma in situ between 2000 and 2010 within a single hospital. A total of 211 patients were included, and the median follow-up was 8.4 years. The effect of detection mode (screen-detected and non-screen-detected) on breast cancer recurrences, readmissions, and complications was evaluated through multivariate logistic regression analysis. Results: In the majority of women, breast ductal carcinoma in situ was screen-detected (63.5%). Screen-detected breast ductal carcinoma in situ was smaller in size compared to those non-screen-detected (57.53% < 20 mm versus 78.03%, p = 0.002). Overall, breast-conserving surgery was the most frequent surgery (86.26%); however, mastectomy was higher in non-screen-detected breast ductal carcinoma in situ (20.78% versus 9.7%, p = 0.024). Readmissions for mastectomy were more frequent in non-screen-detected breast ductal carcinoma in situ. Psychological complications, such as fatigue, anxiety, and depression, had a prevalence of 15% within our cohort. Risk of readmissions and complications was higher within the non-screen-detected group, as evidenced by an odds ratio = 6.25 (95% confidence interval = 1.95–19.99) for readmissions and an odds ratio = 2.41 (95% confidence interval = 1.95–4.86) for complications. Conclusions: Our findings indicate that women with breast ductal carcinoma in situ breast cancer diagnosed through population-based breast cancer screening program experience a lower risk of readmissions and complications than those diagnosed outside these programs. These findings can help aid women and health professionals make informed decisions regarding screening.
Subsequent risk of ipsilateral and contralateral invasive breast cancer after treatment for ductal carcinoma in situ: incidence and the effect of radiotherapy in a population-based cohort of 10,090 women
