| Objective:The survival rate of patients with stage ⅣB esophageal cancer has improved in recent years.In patients with an initial preoperative diagnosis of stage Ⅰ-Ⅲ and intraoperative pathologically confirmed stage ⅣB esophageal cancer,there are no guidelines suggesting whether lymph node dissection should be pursued.Also,it is unclear whether patients undergoing lymph node dissection for stage ⅣB esophageal cancer surgery will yield a superior survival prognosis.Therefore,we investigated the survival impact of lymph node dissection applied to patients undergoing esophagectomy for stage ⅣB esophageal cancer.Method:Patients with stage ⅣB esophageal cancer who had undergone esophagectomy from 2004-2015 in the SEER database were selected for retrospective analysis.Patients with esophageal cancer were divided into two groups:lymph node dissection and non-lymph node dissection,and analyzed to compare whether there were differences in overall survival(OS)and cancer-specific survival(CSS)between the two groups,with a focus on comparing favorable survival factors for each subgroup in the two groups.Univariate cox regression and multiple cox regression analysis were established to analyze independent prognostic risk factors,and these factors were used to construct nomogram models.Two sets of validation models were established by adding lymph node dissection or not as a prognostic factor,and the C-index evaluated the differentiation of the model,the calibration curve evaluated the calibration of the model,and the Bootstrap method validated the model.Then a decision-making model was built,and the net income levels of these models were compared in different threshold ranges..Result:A total of 372 patients who underwent surgery for stage ⅣB esophageal cancer were included in the study.Of these,161 cases underwent lymph node dissection and 211 cases did not.There was no significant difference in OS(HR:0.90,95%CI:0.72-1.13,p=0.37)and CSS(HR:0.90,95%CI:0.71-1.14,p=0.38)between the two groups.Multivariate regression analysis showed that 60-75 years old,year of diagnosis in 2012-2015,stage N3 in TNM staging,were independent risk factors affecting patients’ CCS and OS.The nomogram model was constructed based on the above independent prognostic factors.Two validation models with or without lymph node dissection were constructed,and the Area Under Curve(AUC)value of Receiver Operating Characteristic Curve(ROC)obtained by validation was 0.736,and the concordance index(C-index)value of the models was 0.653.The AUC value of ROC curve excluding lymph node dissection as a prognostic factor was 0.714,and the C-index value of the models was 0.648,suggesting that the nomogram with lymph node dissection as a prognostic factor had better prognostic prediction on the patients with stage ⅣB esophageal cancer.The calibration curve is in good agreement with the 45° diagonal,suggesting that the model has a good fit.The decision-making curve of the nomographic model was superior to the traditional empirical model in the threshold range of 0.3～0.8,and the model had good net benefit in clinical application.Conclusion:Lymph node dissection does not significantly improve OS and CSS in patients undergoing esophagectomy for stage ⅣB esophageal cancer.Multivariate regression analysis showed that 60-75 years old,year of diagnosis in 2012-2015,stage N3 in TNM staging,and stage G2 in differentiation were independent risk factors for CCS and OS in patients.We also constructed and validated a nomogram model for predicting patients undergoing esophagectomy for stage ⅣB esophageal cancer.The validation results showed that the model had better prognostic value,and also verified that the model with lymph node dissection had better predictive effect than the model without lymph node dissection.This model can well help clinicians to better individualize the risk of death in patients undergoing esophagectomy for stage ⅣB esophageal cancer.The findings may provide some insight into the management of lymph nodes in patients with surgically treated advanced esophageal cancer and provide guidance to clinicians in their practice. |
PDF Full Text Request