A nomogram for predicting survival of patients with locally advanced pancreatic cancer treated with chemoradiotherapy

Background: We developed a nomogram for predicting survival of patients with locally advanced pancreatic cancer (LAPC) after concurrent chemoradiotherapy (CRT) using ¹⁸F-flurodeoxyglucose-positron emission tomography (FDG-PET) parameters and CA 19-9 levels. Methods: Based on 426 patients with LAPC who received concurrent CRT between 2004 and 2015, we investigated significant prognostic factors for survival to build a nomogram, including the maximum standardized uptake value (SUV_max) and CA 19-9 levels. Predictive accuracy and discriminative ability were then measured. Results: Median progression-free survival and overall survival (OS) were 9.4 and 15.4 months, respectively, at a median 15-month follow-up. High-dose radiation (EQD2, ≥61 Gy), initial SUV_max <3.5 and CA 19-9 ≤400 U/mL, and surgical resection after CRT were significantly related to prolonged OS by multivariate analysis (p < 0.05). A nomogram model for OS was established and showed good calibration and acceptable discrimination (c-index 0.656). Using the nomogram, 3 different prognosis groups could be identified with a median OS of 25, 15, and 11 months (p < 0.001). Conclusion: A nomogram was developed with high-dose radiation (EQD2, ≥61 Gy), initial SUV_max <3.5, CA 19-9 ≤400 U/mL, and surgical resection after CRT for patients with LAPC. This will help in clinical decision-making and in selecting patients for CRT.