Pathologic response as predictor of recurrence, metastasis, and survival in breast cancer patients receiving neoadjuvant chemotherapy and total mastectomy.

Abstract

To determine easy-to-use predictors of overall survival (OS), locoregional recurrence (LRR), and distant metastasis (DM) in breast invasive ductal carcinoma (IDC) patients receiving neoadjuvant chemotherapy (NACT) and total mastectomy (TM), we used the pathologic response (PR) of primary breast diseases (T stages), nodal diseases (N stages), and combined primary and nodal diseases (American Joint Committee on Cancer [AJCC] stages) based on existing clinical and pathologic reports as predictors. We enrolled patients with IDC who received NACT followed by TM. Cox regression analysis was used to calculate hazard ratios (HRs) and confidence intervals (CIs) of PR; other independent predictors were controlled for or stratified in the analysis. We analyzed 3654 IDC patients (1031, 1215, 1003, and 405 patients with clinical stages IIB, IIIA, IIIB, and IIIC, respectively) receiving NACT and TM. After multivariate Cox regression analyses, the adjusted HRs (aHRs) (95% CI) for all-cause mortality, LRR, and DM were noted to be 0.21 (0.13-0.34), 0.19 (0.08-0.48), and 0.33 (0.23-0.47), respectively, for pCR; 0.56 (0.48-0.65), 0.67 (0.51-0.89), and 0.61 (0.52-0.70), respectively, for AJCC downstaging; and 1.85 (1.56-2.18), 1.17 (0.84-1.62), and 1.61 (1.36-1.90), respectively, for AJCC upstaging. The PR parameters used in the study are easily applied because they are based on existing staging records, and they can strongly predict OS, LRR, and DM in IDC patients receiving NACT and TM, regardless of clinical stage. The results can be used to guide adjuvant treatment.