Nomogram for predicting the overall survival of patients with inflammatory breast cancer: A SEER-based study.

OBJECTIVES: Inflammatory breast cancer (IBC) is a rare malignancy that is a unique biologic subtype of breast cancer. A nomogram to predict the overall survival (OS) of IBC patients is lacking. The aim of the study was to construct and validate a nomogram to predict the OS of IBC patients based on the Surveillance, Epidemiology, and End Results (SEER) Program.

METHODS: Patients diagnosed with IBC between 2010 and 2016 were selected from the SEER database. Univariate and multivariate Cox regression analyses were used to identify independent prognostic factors. A nomogram was constructed to predict the 1-, 3- and 5-year OS of these patients. The nomogram was internally and externally validated by Harrell's C-indexes and calibration plots.

RESULTS: Patients were randomly divided into a training set (n = 2464) and a validation set (n = 1052). The training set was used to establish a nomogram. Multivariate analysis identified that race, age at diagnosis, breast cancer subtype, grade, N stage, M stage, radiation, chemotherapy, and surgery were significant prognostic factors for the OS. The internally and externally validated Harrell's C-indexes were 0.763 and 0.786, respectively. The calibration plots for predictions of the 1-, 3-, and 5-year OS were in excellent agreement.

CONCLUSIONS: A nomogram was constructed to predict the OS for IBC patients based on the SEER database and to provide accurate and individualised survival predictions.