Nomograms for pre-and postoperative prediction of long-term survival among proximal gastric cancer patients: A large-scale,single-center retrospective study

BACKGROUND The incidence of proximal gastric cancer(GC) is increasing, and methods for the prediction of the long-term survival of proximal GC patients have not been well established.AIM To develop nomograms for the prediction of long-term survival among proximal GC patients.METHODS Between January 2007 and June 2013, we prospectively collected and retrospectively analyzed the medical records of 746 patients with proximal GC,who were divided into a training set(n = 560, 75%) and a validation set(n = 186,25%).A Cox regression analysis was used to identify the preoperative and postoperative risk factors for overall survival(OS).RESULTS Among the 746 patients examined, the 3-and 5-year OS rates were 66.1% and58.4%, respectively.In the training set, preoperative T stage(cT), N stage(cN),CA19-9, tumor size, ASA core, and 3-to 6-mo weight loss were incorporated into the preoperative nomogram to predict the OS.In addition to these variables,lymphatic vascular infiltration(LVI), postoperative tumor size, T stage, N stage,blood transfusions, and complications were incorporated into the postoperative nomogram.All calibration curves used to determine the OS probability fit well.In the training set, the preoperative nomogram achieved a C-index of 0.751 [95%confidence interval(CI): 0.732-0.770] in predicting OS and accurately stratified the patients into four prognostic subgroups(5-year OS rates: 86.8%, 73.0%,43.72%, and 20.9%, P < 0.001).The postoperative nomogram had a C-index of0.758 in predicting OS and accurately stratified the patients into four prognostic subgroups(5-year OS rates: 82.6%, 74.3%, 45.9%, and 18.9%, P < 0.001).CONCLUSION The nomograms accurately predicted the pre-and postoperative long-term survival of proximal GC patients.