P2-12-18: A Prognostic Model Based on Node Status, Cathpesin-D and Ki-67 Predict the Outcome of Patients Failing To Achieve Pathological Complete Response after Anthracycline-Based Neoadjuvant Chemotherapy for Breast Cancer.

Abstract

Abstract Background Aim of this study was to evaluate factors which could possibly affect the outcome of patients failing to achieve pathological complete response (pCR) after anthracycline-based neoadjuvant chemotherapy (NCT) for breast cancer, and built a prognostic model to predict disease free survival (DFS) and overall survival (OS). Material and Methods: We retrospectively collected data of 199 stage II-III breast cancer patients who had failed to achieve pathological complete response after neoadjuvant chemotherapy in Shanghai Cancer Hospital. The NCT regimens were NE (navelbine 25mg/m2, day 1, 8 and epirubicin 60mg/m2, day 1; every three weeks) or CEF (cyclophosphamide 600 mg/m2, day 1; epirubicin 60 mg/m2, day 1 and 5-fluorouracil 600 mg/m2, day 1; every three weeks) for a median treatment course of 3 cycles. To develop the prognostic model, variables at baseline(age, menopausal status, tumor size, node status, ER, PR, and HER-2) and at surgery(tumor size, grade, histotype, node status, vascular invasion, ER, PR, HER-2, Cathpesin-D, P53, Topo-IIα, Nm-23, Bcl-2, BAX, MDR, GSTn, PS2, P27, Cyclin D1 and Ki-67) were investigated. Multivariate Cox regression model and Kaplan-Meier method was used to build the model, and show the discrimination of DFS and OS in different risk groups. Results: By multivariate analysis, ≥4 lymph node metastasis (HR=1.9, P=0.009), Cath-D positive (HR=2.5, P=0.006), and Ki-67 index≥20% (HR=1.9, P=0.001) at surgery were independent predictors for lower DFS and OS rate among non-pCR responders. We built a prognostic scoring model on the basis of these variables, in which ≥4+ nodes, Cath-D + or Ki-67 index≥20% would contribute 1 point separately to the risk score. The 5-year DFS rates in low(0 point), intermediate-low(1 point), intermediate-high(2 points) and high risk groups(3 points) were 94%, 65%, 43%, and 28%, respectively (Log-rank teat p<0.001). The 5-year OS rates in these four groups were 94%, 84%, 66% and 34%, respectively (Log-rank test p<0.001). Conclusion: Post-NCT node status, Cathpesin-D and Ki-67 were used to develop a prognostic model which could simply discriminate patients with poor prognosis among non-pCR responders after anthracycline-based neoadjuvant chemotherapy, and might help to tailor further individualized treatment strategies. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-12-18.