Development of a nomogram to predict the clinical impact of a postexcision preirradiation mammogram

Abstract

We aimed to better quantify the impact of a postexcision preirradiation mammogram (PPM), first by identifying factors associated with abnormal results and then incorporating these findings into a nomogram. Beginning February 2011, our institution made a practice change to obtain a PPM on all patients with any calcifications identified. A total of 530 patients underwent a PPM. Suspicious abnormalities were reported in 61 patients (11.5%), with the PPM leading to a change in management in 47 instances (8.9%). A nomogram was created based on patient and tumor characteristics to identify patients most likely to have an abnormal PPM.