A prognostic nomogram based on risk assessment for invasive micropapillary carcinoma of the breast after surgery

Invasive micropapillary carcinoma (IMPC) is one of the rare subtypes of breast cancer. A total of 1855 IMPC patients diagnosed after surgery between 2004 and 2014 were identified from the Surveillance, Epidemiology and End Results (SEER) database to build a nomogram. Cox regression analysis indicated that age ≥ 62 at diagnosis, negative ER status, and tumor stage were considered adverse independent factors for overall survival (OS), while patients who were married, white or of other races, received chemotherapy or radiotherapy, had a better postoperative prognosis. The nomogram accurately predicted OS with high internal and external validation consistency index (C index) (0.756 and 0.742, respectively). The areas under the receiver operating characteristic (ROC) curves (AUCs) of the training group were 0.787, 0.774 and 0.764 for 3 years, 5 years and 10 years, respectively, while those of the validation group were 0.756, 0.766 and 0.762, respectively. The results of both decision curve analyses (DCA) and calibration curves demonstrated the good performance of the model. This study constructed a novel nomogram for IMPC of the breast patients after surgery, which has good accuracy and consistency in predicting prognosis and has clinical application value.