Personalized nomograms for predicting survival outcomes of operable triple negative breast cancer (TNBC) are scarce. The aim of this study is to develop and validate an effective nomogram to predict disease-free and overall survival for women with early TNBC in China.
The nomogram was based on a retrospectively analysis on 296 invasive operable TNBC women treated at Sun Yat-sen Memorial Hospital from 2002 to 2014. The predictive accuracy and discriminative ability of nomogram were determined by concordance index (C-index) and calibration curve and compared with the seventh American Joint Committee on Cancer (AJCC) staging system. The model was subjected to bootstrap internal validation and to external validation with a separate cohort of 108 patients from the second Xiangya Hospital and Peking University Shenzhen Hospital.
On multivariate analysis of the training cohort, independent factors for outcomes were stromal tumor-infiltrating lymphocytes (TILs), tumor size, node status, and Ki67 index, which were selected into the nomogram. The calibration curves for probability of disease-free survival (DFS) and overall survival (OS) showed optimal agreement between nomogram prediction and actual observation. The C-index of the nomogram was higher than that of the seventh AJCC staging system for predicting DFS (training cohort: 0.730 vs 0.668, respectively, P = 0.026; validation cohort: 0.750 vs 0.676, respectively, P = 0.051) and OS (training cohort: 0.745 vs 0.676, respectively, P = 0.049; validation cohort: 0.810 vs 0.659, respectively, P = 0.278). The stratification into different risk groups allowed significant distinction between survival curves within respective TNM categories.
We developed a novel well-calibrated nomogram that can provide individual prediction of DFS and OS for operable TNBC based on Chinese breast cancer data. This practical prognostic model can help clinicians in decision making and surveillance recommendation.
Jieqiong Liu
The National Natural Science Foundation of China
All authors have declared no conflicts of interest.