Abstract P4-08-14: Invasive micropapillary carcinoma had no difference in prognosis compared with invasive ductal carcinoma: A propensity-matched analysis

Abstract

Abstract Background: Invasive micropapillary carcinoma (IMPC) is a rare histopathological variant of breast carcinoma and usually performs poor clinical characteristics, such as high tendency of lymph nodes metastases. But whether it has worse prognosis than invasive ductal carcinoma (IDC) is still controversial nowadays. We conducted this retrospective study to figure out the prognostic difference between IMPC and IDC, then guide therapy of IMPC ultimately. Methods: In this study, we analyzed 327 cases of IMPC patients and 4979 cases of IDC who underwent primary resection in our institution during 2008 to 2012. By using propensity score matching, two groups were matched at a ratio of 1:1 by age, tumor size, nodal status, hormone and HER2 status to demonstrate the difference of prognosis assessed by Kaplan-Meier estimates and Cox regression analysis. Result: After a mean follow-up of 52 months, we established the IMPC group and figured out 324 IDC patients from the control group by propensity score matching (3 IMPC patients were canceled because of data missing). The result of survival analysis indicated that women diagnosed with IMPC had no significant reduced overall survival (OS) (p = 0.752) and disease-free survival (DFS) (p = 0.578) compared with women with IDC. Multivariate Cox regression analysis revealed that IMPC was not found as an independent prognostic factor for DFS (hazard ratio [HR] = 0.858; 95% confidential interval [CI], 0.419-1.757) or OS (HR = 0.720; 95%CI, 0.353-1.469). Conclusion: The consequence of survival analysis manifested that there was no statistically significant difference between 2 groups, and elucidated proactive or radical clinical therapy was unnecessary. Citation Format: Hao S, Zhao Y-Y, Peng J-J, Yang W-T, Ren F, Yu K-D, Shao Z-M. Invasive micropapillary carcinoma had no difference in prognosis compared with invasive ductal carcinoma: A propensity-matched analysis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-08-14.