Prognostic Value Of Lymph Node Ratio-Based Staging System In Gallbladder Carcinoma With Less Than 6 Lymph Nodes Dissected

Objective:To investigate the prognostic value of TNM staging system based on lymph node ratio(LNR)in patients with gallbladder cancer with less than 6 lymph nodes dissected.Methods:A retrospective study was performed to analyze the clinical and pathological data of GBC patients who have underwent radical surgery from January 2010 to June 2021 in the Affiliated Hospital of North Sichuan Medical College.Finally,153 GBC patients were included,of which 97 were female,with an average age of 60.7±11.0 years.According to the number of lymph nodes dissected,they were divided into inadequate lymph node dissection group(ILND group,n=117)and adequate lymph node dissection group(ALND group,n=36).Calculate LNR optimal cutoffs and construct LNR staging.The TNrM staging system and the 8th edition TNM staging system were used to stage the two groups of patients respectively,and the Kaplan-Meier method was used for survival analysis.Prognostic factors were analyzed for gallbladder cancer with less than 6 lymph nodes dissected.Results:1.Among 153 GBC patients,the majority of patients had fewer than 6 lymph nodes dissected(n=117,76.5%).The average number of lymph nodes dissected was 3.4±1.9,and the average number of dissected lymph nodes in the ILND group was 2.9 ± 1.4,which was significantly lower than that in the ALND group(6.9±1.5),and the difference between the two groups was statistically significant(t=-12.061,P＜0.001).Compared with the ALND group,the ILND group had a higher proportion of poorly differentiated tumors(94.4%vs.72.3%),shorter operative time(248±92 vs.315±64),less postoperative adjuvant therapy(18.8%vs.44.4%),and less intraoperative blood transfusion(21.4%vs.38.9%),the difference was statistically significant(all P<0.05).2.The optimal cutoff value for LNR was 0.56(χ2=46.838,P<0.0001).3.The median survival time of all patients included in this study was 18.0 months,and the 1-,3-,and 5-year survival rates were 65.1%,38.1%,and 24.1%,respectively.4.The prognostic accuracy of TNrM staging system for GBC and gallbladder adenocarcinoma with less than 6 lymph nodes dissected was 0.742(95%CI:0.695-0.789)and 0.756(95%CI:0.707-0.805),respectively.The prognostic accuracy of the eighth edition of TNM staging system for GBC and gallbladder adenocarcinoma with less than 6 lymph nodes dissected was 0.706(95%CI:0.661-0.751)and 0.736(95%CI:0.687-0.785),respectively.5.The prognostic accuracy of TNrM staging system for GBC and gallbladder adenocarcinoma patients with ≥6 lymph nodes dissected was 0.786(95%CI:0.702-0.870)and 0.804(95%CI:0.761-0.867),respectively.The prognostic accuracy of the eighth edition TNM staging system for GBC and gallbladder adenocarcinoma patients with ≥6 lymph nodes dissected was 0.807(95%CI:0.731-0.883)and 0.826(95%CI:0.758-0.894),respectively.6.CEA,intraoperative blood transfusion,T staging,N staging,LNR staging,liver invasion,vascular invasion,histological differentiation,and surgical margin status are prognostic factors for GBC with less than 6 lymph node dissection;T staging,LNR staging,vascular Invasion and surgical margin status were independent risk factors for GBC with less than 6 lymph node dissection.Conclusion:1.The best cutoff value for LNR is 0.56.2.For GBC patients with less than 6 lymph nodes dissected,the prognostic stratification ability of the TNrM staging system may be better than that of the eighth edition of the TNM staging system.The TNrM staging system can be used as a supplement or alternative to the eighth edition of the TNM staging system to achieve more effective prognostic assessment and treatment.3.T staging,LNR staging,vascular invasion,and surgical margin status were independent risk factors for GBC with less than 6 lymph node dissection.