Abstract
PURPOSE: To establish and validate a nomogram for predicting pathological complete response (pCR) after neoadjuvant therapy (NAT) in breast cancer (BC) patients, aiming to identify subgroups potentially suitable for non-surgical management. METHODS: Between 2010 and 2015, 4402 BC patients (3037 surgery, 1365 non-surgery) were extracted from the Surveillance, Epidemiology, and End Results (SEER) database, with external validation in 339 BC patients from our hospital. Logistic regression identified pCR predictors and a nomogram model was constructed. Propensity score matching (PSM) was applied to minimize the effect of the imbalance of the prognostic factors between the surgery group and the non-surgery group. RESULTS: Univariable and multivariable analyses revealed that age, marital status, T stage, N stage, differentiation grade, hormone receptor (HR) status, human epidermal growth factor receptor 2 (HER2) status and chemotherapy were significant predictors of pCR in the surgery group (all p < 0.05). The area under the receiver operating characteristic curve (AUC) for predicting pCR was 0.756 (95% CI: 0.736-0.776), 0.717 (95% CI: 0.681-0.754), and 0.744 (95% CI: 0.687-0.800) in the training, internal validation, and external validation sets, respectively. Non-surgery patients were stratified into high (> 375), medium (162.5-375), and low (< 162.5) nomogram score groups, with 5-year OS rates of 70.7%, 49.2%, and 29.2% (p < 0.05). After PSM, 358 pairs of patients were included to compare 5-year OS between the surgery group and the non-surgery group, and the results showed that the 5-year OS of patients stratified by high-score group, medium-score group and low-score group between the surgery group and the non-surgery group were 85.4% vs. 72.8%, 78.3% vs. 59.8% and 79.3% vs. 20.0% (all p < 0.05). CONCLUSION: We successfully established a nomogram for pCR in BC patients. Based on this predictive model, patients with higher scores may represent potential candidates for non-surgical therapeutic approaches, warranting further investigation in future studies.