Comparison of breast ductal carcinoma in situ and ductal carcinoma in situ with microinvasion, and analysis of axillary lymph node metastasis

To compare the clinicopathologic features and long-term outcomes for women with ductal carcinoma in situ (DCIS) vs DCIS with microinvasion (DCISM), to assess the impact of microinvasion on tumor size and determine relationships between the number of microinvasive lesions and clinicopathological factors. A total of 493 patients with DCIS or DCISM from our database were analyzed to assess differences in clinicopathologic features and outcomes between the 2 cohorts. The median follow-up was 3.9 years, 229 patients had DCIS and 264 had DCISM, and the mean age was 46.8 years for the entire group. A total of 208 patients underwent axillary operation in the DCIS cohort vs 246 in the DCISM cohort, and the number of lymph node metastasis cases was 0 vs 13 for the 2 groups. For the lymph node-positive cases, the proportion of patients with no less than 3 microinvasive legions was 61.5% (8/13), while in the lymph node-negative group, the proportion of patients was 31.1% (78/251) (P