Objective:To investigate the clinicopathological characteristics and prognosis of non-specific invasive breast cancer (BIC-NST) patients with and without ductal carcinoma in situ (DCIS).Methods:A retrospective cohort study was conducted. A total of 9 490 female BIC-NST patients who underwent surgery in the Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College and the Yuncheng Central Hospital in Shanxi Province from January 2009 to December 2017 were collected. Among them, 4 248 cases (44.8%) had DCIS and 5 242 cases (55.2%) did not have DCIS. The clinicopathological characteristics and prognosis of BIC-NST patients with and without DCIS were compared. Cox proportional hazards model was used to make univariate and multivariate analysis on the influencing factors of overall survival (OS) and disease-free survival (DFS) in BIC-NST patients.Results:Compared with patients without DCIS, patients with DCIS were younger [(51±11) years vs. (53±11) years, t = -8.75, P < 0.001], had a lower proportion of breast conserving surgery [19.2% (815/4 248) vs. 21.2% (1 113/5 242), χ2 = 6.07, P = 0.010], a higher proportion of pathological T 1 stage [60.2% (2 558/4 248) vs. 57.5% (3 016/5 242), χ2 = 6.96, P = 0.008], a lower histological grade, a lower Ki-67 positivity index [(28±19)% vs. (31±22)%, χ2 = -5.84, P < 0.001], a higher proportion of lymphatic vessel invasion [18.3% (777/4 248) vs. 15.9% (831/ 5 242), χ2 = 9.91, P = 0.002], higher positivity rates of hormone receptor (HR) [78.9% (3 278/4 248) vs. 76.2% (3 907/5 242), χ2 = 9.02, P = 0.003] and human epidermal growth factor receptor 2 (HER2) [31.3% (1 236/4 248) vs. 21.2% (1 029/5 242), χ2 = 117.64, P < 0.001], a lower proportion of patients with HR - HER2 - [9.0% (353/ 4 248) vs. 16.5% (800/5 242), χ2 = 138.68, P < 0.001] and HR + HER2 - [59.8% (2 354/4 248) vs. 62.4% (3 026/5 242), χ2 = 8.50, P = 0.004]. Survival analysis showed that there were no statistically significant differences in OS and DFS between patients with and without DCIS ( χ2 = 1.05, P = 0.310; χ2 = 0.42, P = 0.520). Univariate analysis showed that DCIS had no effect on the OS ( HR = 0.926, 95% CI: 0.799-1.073, P = 0.306) and DFS ( HR = 1.040, 95% CI: 0.924-1.170, P = 0.518) of BIC-NST patients. Conclusions:The clinicopathological characteristics of BIC-NST patients with and without DCIS are different, while the presence of DCIS does not affect the prognosis of BIC-NST patients.

Objective:To investigate the clinicopathological characteristics and prognosis of non-specific invasive breast cancer (BIC-NST) patients with and without ductal carcinoma in situ (DCIS).Methods:A retrospective cohort study was conducted. A total of 9 490 female BIC-NST patients who underwent surgery in the Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College and the Yuncheng Central Hospital in Shanxi Province from January 2009 to December 2017 were collected. Among them, 4 248 cases (44.8%) had DCIS and 5 242 cases (55.2%) did not have DCIS. The clinicopathological characteristics and prognosis of BIC-NST patients with and without DCIS were compared. Cox proportional hazards model was used to make univariate and multivariate analysis on the influencing factors of overall survival (OS) and disease-free survival (DFS) in BIC-NST patients.Results:Compared with patients without DCIS, patients with DCIS were younger [(51±11) years vs. (53±11) years, t = -8.75, P < 0.001], had a lower proportion of breast conserving surgery [19.2% (815/4 248) vs. 21.2% (1 113/5 242), χ2 = 6.07, P = 0.010], a higher proportion of pathological T 1 stage [60.2% (2 558/4 248) vs. 57.5% (3 016/5 242), χ2 = 6.96, P = 0.008], a lower histological grade, a lower Ki-67 positivity index [(28±19)% vs. (31±22)%, χ2 = -5.84, P < 0.001], a higher proportion of lymphatic vessel invasion [18.3% (777/4 248) vs. 15.9% (831/ 5 242), χ2 = 9.91, P = 0.002], higher positivity rates of hormone receptor (HR) [78.9% (3 278/4 248) vs. 76.2% (3 907/5 242), χ2 = 9.02, P = 0.003] and human epidermal growth factor receptor 2 (HER2) [31.3% (1 236/4 248) vs. 21.2% (1 029/5 242), χ2 = 117.64, P < 0.001], a lower proportion of patients with HR - HER2 - [9.0% (353/ 4 248) vs. 16.5% (800/5 242), χ2 = 138.68, P < 0.001] and HR + HER2 - [59.8% (2 354/4 248) vs. 62.4% (3 026/5 242), χ2 = 8.50, P = 0.004]. Survival analysis showed that there were no statistically significant differences in OS and DFS between patients with and without DCIS ( χ2 = 1.05, P = 0.310; χ2 = 0.42, P = 0.520). Univariate analysis showed that DCIS had no effect on the OS ( HR = 0.926, 95% CI: 0.799-1.073, P = 0.306) and DFS ( HR = 1.040, 95% CI: 0.924-1.170, P = 0.518) of BIC-NST patients. Conclusions:The clinicopathological characteristics of BIC-NST patients with and without DCIS are different, while the presence of DCIS does not affect the prognosis of BIC-NST patients.