ABSTRACT
Objective To explore the long-term outcomes and prognostic factors of laparoscopic gastrectomy for stage T4a gastric cancer.Methods The retrospective case-control study was conducted.The clinicopathological data of 224 patients who underwent laparoscopic gastrectomy of gastric cancer and D2 lymph node dissection in the Ruijin Hospital of Shanghai Jiaotong University School of Medicine between February 2004 and December 2014 were collected.Lymph node dissection followed the Japanese Gastric Cancer Treatment Guidelines (13th edition).Anastomotic methods included Billroth Ⅰ,Billroth Ⅱ and Roux-en-Y gastrojejunostomy or esophagojejunostomy.Patients who were diagnosed in stage T4a by postoperative pathological examination underwent 5-fluorouracil chemotherapy.Observation indicators:(1) treatment;(2) postoperative pathological examination;(3) follow-up;(4) prognostic factors analysis.Follow-up using outpatient examination and telephone interview was performed to detect the postoperative tumor recurrence or metastases up to death (end of follow-up) or July 31,2016.Measurement data with normal distribution were represented as x±s and comparison between groups was analyzed using Student-t test.Measurement data with skewed distribution were described as M (Q).Comparisons of count data were analyzed using the chi-square test.The overall and disease-free survival curves,overall and disease-free survival rates were respectively drawn and calculated using the Kaplan-Meier method.The survival analysis was done by the Log-rank method.The univariate analysis was done by the chisquare test,and COX regression model which included affecting factors (P＜0.10) in the univariate analysis was used for the multivariate analysis.Results (1) Treatment:all the 244 patients underwent successful operation,without conversion to open surgery.Surgical method:laparoscopic-assisted distal gastrectomy (4 combined with cholecystectomy,1 with splenectomy and 1 with transverse colectomy) were detected in 125 patients and laparoscopic-assisted total gastrectomy in 99 patients (3 combined with cholecystectomy and 2 with splenectomy).Anastomotic method:Billroth Ⅰ,Billroth Ⅱ and Roux-en-Y gastrojejunostomy or esophago-jejunostomy were respectively applied to 85,29 and 110 patients.Operation time and volume of intraoperative blood loss were (229±50)minutes and (229 ± 146)mL.All patients underwent 6 or 8 cycles 5-fluorouracil chemotherapy.(2)Postoperative pathological examination:numbers of lymph node dissected and positive lymph nodes were 25± 11 per case and 13 (8,25),with R0 resection.Tumor pathological diagnosis of 224 patients:tumor diameter was (4.5±2.3)cm.Tumors in 29,64,122 and 9 patients respectively located in 1/3 proximal stomach,1/3 middle segment of stomach,1/3 distal stomach and involving 2/3 or total stomach.Tumor differentiation:moderate-and high-differentiated tumors and low-and un-differentiated tumors were detected in 82 and 142 patients,respectively.Postoperative N staging:53,46,55 and 70 patients were detected in staging N0,N1,N2 and N3,respectively.Lymph node metastasis rates of 51,58,53 and 62 patients were 0,1％-15％,16％-40％ and ＞40％,respectively.Postoperative staging was T4a staging.(3) Follow-up:212 of 224 patients were followed up for 7-120 months,with a median time of 32 months.Of 212 follow-up patients,118 were survived and 94 died.Of 118 survived patients,13 and 105 were respectively survived with tumors and without tumor.Of 94 deaths,causes of 8 and 86 were respectively non-tumor and tumor-related deaths.The 5-year overall and disease-free survival rates of 224 patients were respectively 47.2％ and 43.6％.(4) Prognostic factors analysis:results of univariate analysis showed that tumor location,tumor diameter,N staging and lymph node metastasis rate were related factors affecting the postoperative 5-year overall and disease-free survival rates of patients undergoing laparoscopic gastrectomy of stage T4a gastric cancer (x2 =6.365,3.740,32.232,48.977,P＜0.10;x2 =9.919,8.818,34.277,45.612,P＜ 0.10).Results of multivariate analysis showed that lymph node metastasis rate was an independent factor affecting the postoperative 5-year overall and disease-free survival rates of patients undergoing laparoscopic gastrectomy of stage T4a gastric cancer (HR =1.828,1.197,95％ confidence interval:1.353-2.469,0.945-1.516,P＜0.05).Postoperative 5-year overall and disease-free survival rates were respectively 72.5％,57.0％,41.6％,23.3％ and 70.0％,53.9％,37.0％,32.4％in staging N0,N1,N2 and N3 patients,with statistically significant differences in different staging (x2 =32.232,34.277,P＜0.05).Conclusion There are good long-term outcomes in laparoscopic gastrectomy for stage T4a gastric cancer,and lymph node metastasis rate is an independent factor affecting postoperative overall and disease-free survival of patients.