Abstract P2-07-12: A prognostic prediction nomogram (PDIDC) for breast Paget's disease with infiltrating ductal carcinoma patients: A SEER cohort analysis

Purpose The aim of the study was to develop a specific nomogram for prediction of prognosis for breast Paget9s disease with infiltrating ductal carcinoma (PD-IDC) patients. Patients and Methods Patients data were obtained by the Surveillance, Epidemiology, and End Results (SEER) program (N=2502). Study outcome was Breast Cancer Specific Survival (BCSS). Cox proportional hazards model was applied to identify risk factors and develop predictive model. For internal validation, discrimination was calculated with the concordance index (C-index) using the bootstrap method and calibration assessed. Results NPI classification, skin symptom, tumor site and age showed significant association with BCSS(table.1)and were used to build the PDIDC nomogram and to calculate risk score. PDIDC nomogram9s C-index (0.791, 95%CI 0.783-0.818) showed better discrimination power than NPI classification (0.691, 95%CI, 0.650-0.735, P= 0.000) and AJCC staging (0.718, 95%CI, 0.695-0.741, P=0.000). Patients were divided into high-risk (1882/2502, 75.21%) and low-risk (620/2502, 24.78%) subgroups with the optimal cut-off of risk scores (4.28). The total BCSS of low-risk subgroup was 77.8% (95%CI 74.4%-81.4%) vs. 31.1% (95%CI 19.4-49.8) of high-risk group (P=0.000). Bootstrap internal validation demonstrated an average C-index of 0.739 (95% CI, 0.692-0.746). The nomogram calibration was validated to be accurate in predicting 5-year and 10-year survival. Conclusion Utilizing NPI classification, skin symptom, tumor site and age, we developed the PDIDC nomogram to predict the 5-year and 10-year BCSS of breast PD-IDC patients. Citation Format: Tan L, Chen K, Jiang WG, You N, Wang Y, Sanders A, Liang G, Liu Z, Ling Y, Zhong W, Tian Z, Gong C. A prognostic prediction nomogram (PDIDC) for breast Paget9s disease with infiltrating ductal carcinoma patients: A SEER cohort analysis [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-07-12.