Establishment And Validation Of Prognostic Nomogram Model For Advanced Gastric Cancer

Study 1 Establishment and Validation of Prognostic Model for Patients with Stage Ⅱ/Ⅲ Gastric Cancer after Radical SurgeryBackground and PurposesGastric cancer(GC)is one of the most common gastrointestinal malignancies,with increasing morbidity and mortality year by year.Gastric cancer has a high incidence in China,and its morbidity and mortality are second only to lung cancer,which seriously endangers people’s life and health and is the focus of cancer prevention and treatment in China.In China,the majority of patients are usually in advanced stage when diagnosed,and the prognosis of advanced gastric cancer is mostly poor.The comprehensive treatment based on surgical resection is the main treatment method for advanced gastric cancer,but the survival rate is still not optimistic,and many patients often die because of unexpected recurrence and metastasis after treatment.Therefore,the prediction of individual prognosis is particularly important.At present,the prognosis of patients is mainly monitored according to the 8th edition of UICC/AJCC-TNM staging system,hematological indexes and pathological features.However,the prognosis of advanced gastric cancer varies greatly,even if the patients are in the same clinical stage or have similar levels of hematological indicators,the prognosis still varies greatly.ln recent years,the nomogram model has shown excellent performance in predicting the individual prognosis of tumor patients.the nomogram model can integrate various prognostic indexes of tumor patients and make up for the prediction limitation of a single index.It can accurately predict the prognosis of individual patients.At present,there is still a lack of effective prognostic tools for advanced gastric cancer,so the nomogram model can help to predict the prognosis and recurrence of patients with advanced gastric cancer.We aim to build and validate a novel individualized nomogram based on inflammation index and tumor markers for stage Ⅱ/ⅢGC.MethodsA total of 755 individuals with stage Ⅱ/Ⅲ GC who had undergone radical gastrectomy at the First Affiliated Hospital of Zhengzhou University between January 2012 and December 2017 were included in this retrospective study.The patients were randomly divided into a training cohort(n=503)and a validation cohort(n=252)according to the ratio of 2:1.Univariate and multivariate Cox analyses were used to determine independent prognostic factors for overall survival(OS)and disease-free survival(DFS).Nomogram models were developed based on these independent factors.The concordance index(C-index)and calibration curves were used to evaluate the predictive accuracy of the nomogram,and finally validate by the internal validation cohort.ResultsUnivariate and multivariate analyses demonstrated that age(>60 years),histological grade(G3-4),T stage(T3-4),N stage(N2-3),neutrophil lymphocyte ratio(NLR>3.1),hemoglobin(≤146.5g/L),carcinoembryonic antigen(CEA>5.1 ng/mL)and carbohydrate antigen 19-9(CA19-9>13.9U/mL)were significantly associated with inferior OS and DFS,and were independent prognostic factors for stage Ⅱ/Ⅲ GC.The nomogram model developed based on these factors in the training cohort showed excellent calibration and discrimination(C-index=0.739,95%CI=0.706-0.772).By comparing the area under the ROC curve(AUC),the results showed that tumor markers and inflammatory parameters were important prognostic factors for predicting OS and DFS,and the prediction accuracy of the prognostic model was higher than that of a single indicator.In the internal validation cohort,the nomogram model was also well-calibrated for prediction of OS and DFS;it was superior to the 8th edition UICC/AJCC-TNM staging system(OS:C-index=0.746 vs.0.679;DFS:C-index= 0.743 vs.0.677,P<0.001).ConclusionWe established and validated a novel nomogram model to predict OS and DFS for stage Ⅱ/Ⅲ GC patients with radical gastrectomy.The nomogram showed good predictive performance and may be helpful for clinical decision guidance and individual prognostic evaluation.Study 2 Prognostic Predictors Analysis of M1 Gastric Cancer and Establishment of Nomogram ModelBackground and PurposesGastric cancer(Gastric Cancer,GC))is the fifth most common cancer in the world and the second most common cause of cancer death in China.Gastric cancer has a poor prognosis,especially for M1 gastric cancer(M1GC),with a median survival of less than 1 year.M1 gastric cancer is associated with distant metastasis,including distant lymph node(non-regional lymph node)metastasis,peritoneal metastasis,and blood-derived metastasis.At present,few studies have systematically described the effect of metastatic patterns on patient survival.In recent years,histograms have been widely used in oncology,such as esophageal cancer,breast cancer,etc.,but rarely involved in M1 gastric cancer.Compared with other stages,patients with M1 gastric cancer have a poor prognosis and unpredictable survival time.The nomogram model can integrate the pathological parameters and prognostic factors of M1 gastric cancer patients,improve the accuracy of individualized survival prediction of M1 gastric cancer patients,and provide help for clinic.Our aim was to evaluate the influence of clinicopathological features on overall survival(OS)in patients with M1 gastric cancer and to construct a novel nomogram to predict overall survival(OS).MethodsThe information of M1GC patients from 2012 to 2018 was derived from the First Affiliated Hospital of Zhengzhou University.Clinicopathological features were compared between LTS(long-term survivals:≥1 year)and STS(short-term survivals:<1 year).Multivariate cox regression analysis was used to determine the independent prognostic factors.A nomogram was constructed based on these factors to predict 1-and 2-year OS in patients with M1GC.Survival curves were drawn by the Kaplan-Meier method to compare the survival of different metastatic patterns.The concordance index(C-index)was used to evaluate the accuracy of model.Calibration curves were used to evaluate the discrimination of the nomogram.ResultsA total of 278 patients diagnosed with distant metastasis at first admission were included in this study.Univariate and multivariate analysis showed that gender,histological grade,chemotherapy and the number of metastatic pattern(NMP)were independent risk factors for OS·in patients with M1GC.By comparing LTS and STS,we confirmed that NMP at initial diagnosis was significantly associated with OS.A prognostic nomogram was constructed based on these independent factors,with a C-index of 0.60(0.573-0.626).The calibration curves showed a good discrimination.ConclusionMetastatic pattern was closely related to the prognosis of M1GC.We established a prognostic model with good predictive performance to predict 1-and 2-year OS in patients with M1GC,which can provide assistance for clinical decision.