Objective: The purpose of this study was to investigate the prognostic implications of post-neoadjuvant chemotherapy on the survival outcomes of breast cancer patients with persistent positive axillary lymph nodes by performing a stage-to-stage comparison between neoadjuvant chemotherapy and initial surgery.
Methods: Retrospective analysis was performed on 813 breast cancer patients with positive axillary lymph node after surgery, who were treated between 2001 and 2006. Of these, 269 patients received neoadjuvant chemotherapy, and 544 patients were treated with surgery followed by adjuvant chemotherapy. The median follow-up time was 5.9 years.
Results: The 5-year disease-free survival rates for patients in the neoadjuvant chemotherapy and adjuvant chemotherapy groups were 73 and 88%, respectively (P<0.001). The 5- and 9-year disease-free survival rates for ypStage II (82 and 76%) were significantly worse than those for pStage II (93 and 80%, P=0.002), and the rates for ypStage III (64 and 50%) were worse than those for pStage III (74 and 66%, P=0.04). The disease-free survival of ypStage II was similar to that of pStage III (P=0.16). Similar results were seen when comparing distant metastasis-free survival rates. Using multivariate analyses, grade, age, hormonal receptor status, final pathological stage and neoadjuvant chemotherapy itself were found to be independent negative prognostic factors for disease-free survival.
Conclusions: Stage-to-stage comparison of pathologically node-positive patients revealed that the survival outcome at each ypStage after neoadjuvant chemotherapy was worse than that for the comparable pStage. These data may help to formulate more accurate prognoses for patients with residual positive nodes after neoadjuvant chemotherapy.