Purpose: This study aimed to identify clinical factors that are of prognostic significance or that predict for subsequent treatment outcome in patients with large operable breast cancer treated with primary chemotherapy (PCT) at our institution.
Methods: One hundred eighty-five patients received the following regimens: CMF or MMM (76 patients), ECF (75 patients), AC or FEC (34 patients), followed by surgery, with radiotherapy (RT) given to those with breast conservation. A number of common clinical variables were assessed in relation to local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS).
Results: Clinical responders had improved DFS (P = .009) and OS (P = .08) compared with nonresponders. There was no association between clinical or pathologic complete remission (CR) and survival. Pretreatment clinical axillary node positivity was a significant predictor of worsened DFS (P = .0001), OS (P = .0001), and LRFS (P = .03). Patients remaining clinically node-positive postchemotherapy had an inferior outcome compared with those becoming node-negative (DFS, P = .03; OS, P = .03) but pathologic axillary node status was not shown to predict for survival. Twenty-nine patients in clinical CR following PCT who electively did not have surgery and were treated with RT alone had significantly increased local recurrence rate compared with partial responders having surgery and RT (P = .02). There were no differences in DFS or OS between these groups. On multivariate analysis, clinical axillary node status was the only independent predictor of OS and DFS, and LRFS.
Conclusion: Pretreatment and posttreatment clinical axillary node status is a major predictor of outcome following PCT. Complete clinical response does not define a more favorable subgroup compared with those not obtaining CR.