No Excess Mortality in Patients Aged 50 Years and Older Who Received Treatment for Ductal Carcinoma In Situ of the Breast

Background. The incidence of ductal carcinoma in situ (DCIS) has increased at a fast rate.The aim of this study was to assess the incidence and treatment in the Netherlands and estimate the excess mortality risk of DCIS. Methods. From the Netherlands Cancer Registry, adult female patients (diagnosed 1997-2005) with DCIS were selected. Treatment was described according to age. Relative mortality at 10 years of follow-up was calculated by dividing observed mortality over expected mortality. Expected mortality was calculated using the matched Dutch general population. Results. Overall, 8421 patients were included in this study. For patients aged 50-64, and 65-74 an increase in breast-conserving surgery was observed over time (P < 0.001). For patients over 75 years of age, 8.0% did not undergo surgery; this percentage remained stable over time (P = 0.07). Overall, treated patients aged >50 years experienced no excess mortality regardless of treatment (relative mortality 1.0). Conclusion. The present population-based study of almost 8500 patients showed no excess mortality in surgically treated women over 50 years with DCIS.