Nomogram for predicting survival in triple-negative breast cancer patients with histology of infiltrating duct carcinoma: a population-based study.

Triple-negative breast cancer (TNBC) represents around 15%-20% of newly diagnosed breast cancer and is more aggressive than other breast cancer sub-types. Infiltrating duct carcinoma (IDC) is the most common type of TNBC. Nomogram is a valuable tool for prognosis prediction by integrating different biological and clinical variables. The purpose of current study was to evaluate the prognostic value of clinical factors of TNBC patients with IDC histology type and construct nomograms for their outcome prediction. The cohort was selected from Surveillance, Epidemiology, and End Results (SEER) program. Univariate and multivariate analyses were performed using Cox proportional hazards regression model to evaluate the prognostic value of involved variables. Nomogram was constructed from the multivariate logistic regression model to combine all the prognostic factors to predict the 1-year and 3-year prognosis of TNBC patients with histology of IDC. Internal validation of nomogram was tested by discrimination and calibration. We identified 14,538 patients with the median and max survival time was 28 months and 59 months, respectively. There were 1,592 deaths, accounting for 10.9% of the cohort. Multivariate analyses showed that grade, tumor stage, tumor size, regional nodes positive, marital status, experience of radiotherapy or chemotherapy were independent prognostic factors of IDC of TNBC. Eleven variables were combined to construct 1-year and 3-year nomograms. It was revealed that the C-index of the nomograms was 0.763 and the calibration curves showed good agreement between the nomogram prediction and actual observation. Current study was the first one to construct nomograms of TNBC patients with IDC histology, which could help physicians to identify patients at high risk for intensive treatment or follow-up.