Clinicopathologic characteristics of ductal carcinoma in situ and risk of subsequent invasive breast cancer: a multicenter, population-based cohort study

Purpose: To study the association between clinicopathologic characteristics of ductal carcinoma in situ (DCIS) and risk of subsequent invasive breast cancer (IBC). Methods: We conducted a case–control study nested in a multicenter, population-based cohort of 8175 women aged ≥ 18 years with DCIS diagnosed between 1987 and 2016 and followed for a median duration of 83 months. Cases (n = 497) were women with a first diagnosis of DCIS who developed a subsequent IBC ≥ 6 months later; controls (2/case; n = 959) were matched to cases on age at and calendar year of DCIS diagnosis. Univariable and multivariable conditional logistic regression models were used to examine the associations between the DCIS characteristics of interest (non-screen detection of DCIS, tumor size, positive margins, grade of DCIS, necrosis, architectural pattern, microcalcification, and estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status) and risk of IBC. Results: In the total study population, the associations were largely null. In subgroup analyses, there were strong position associations with punctate necrosis (pre/perimenopausal women), detection by physical exam (postmenopausal women), architectural patterns other than the main types (breast-conserving surgery [BCS]), and DCIS margins (ipsilateral cases), and inverse associations with HER2 positivity (BCS) and microcalcification (mastectomy); however, the associated confidence intervals were mostly very wide. Conclusion: The results of this study provide limited support for associations of the DCIS clinicopathologic characteristics studied here and risk of IBC.