Efficacy Analysis Of Neoadjuvant Chemotherapy Combined With Laparoscopic Radical Resection Of Colon Cancer For Locally Advanced Colon Cancer

Objectives:To study the feasibility and safety of neoadjuvant chemotherapy combined with laparoscopic radical resection of colon cancer for locally advanced colon cancer(LACC),and toexplore the potential value of neoadjuvant chemotherapy(n CT)in the treatment of LACC.Methods:Medical records were retrospectivelyretrived for LACCpatients who underwent laparoscopic radical resectionat the Fujian Provincial Hospital January2012 to December 2015.Inclusion criteria were endoscopic biopsycomfirmed,XELOX(oxaliplatin + capecitabine)chemotherapy regimen,CT verified colon cancer at clinical stage T4 or T3 with extramural depth ≥5mm.Patients with any metastasisesor history of malignant tumors were excluded.A total of 444 patients were included in this retrospective cohort study.Patientswere divided intoneoadjuvant chemotherapy group(n=42)and adjuvant chemotherapy group(n=402)according to whether the treatment plan containing neoadjuvant chemotherapy.Patients in the neoadjuvant chemotherapy group received four cycles of the XELOX regimen before laparoscopic radical resection of colon cancer.Patients in the adjuvant chemotherapy group underwent radical surgery directly.After using propensity score matching(PSM),there was no significant difference in baseline data between the neoadjuvant chemotherapy group and adjuvant chemotherapy group.The χ2 test or Fisher exact probability method was used to compare the perioperative data and pathological data of the two groups,and the Kaplan-Meier method and Log-rank test were used to compare the disease-free survival and overall survival of the two groups.Results: There were no significant differences in baseline characteristics between two groups after applying propensity score-matching at a ratio of 1:2 for neoadjuvant chemotherapy(n=42)andadjuvant chemotherapy(n=84)groups.After receiving the 4-cycle XELOX regimen,2 patients(4.8%)got a CR(complete response)evaluation,and there were 34 patients(81.0%)got a PR(partial response)evaluation and 6 patients(14.2%)got a SD(stable disease)evaluationbased on RECIST.No progression was found and no emergency surgery occurred during neoadjuvant chemotherapyperiod.Operation time,estimated blood loss,time to bowel movement,time to liquid diet,time to soft diet,and length of hospital stay,incidence of postoperative complications(incision infection,intestinal obstruction,anastomotic leakage)were similar between the two groups(P > 0.05).The postoperative T0-T2 T,T3and T4 stages of the neoadjuvant chemotherapy group were 34.5%(12/42),54.8%(23/42),and 16.6%(7/42)respectively and the postoperative T3 and T4 stages of the adjuvant chemotherapy group were34.5%(29/84)and 65.5%(55/84).The postoperative pathological T stage of theneoadjuvant chemotherapy group was earlier than that of theadjuvant chemotherapy group(P > 0.05).Neoadjuvant chemotherapy group achieved significant smaller tumor size than adjuvant chemotherapy group(3.1±2.1 vs.5.8±2.5cm,P= 0.000),but there’s nosignificant difference for N stage,vascular invasionandinvasion,perineural invasion(P > 0.05).Neoadjuvant chemotherapy group has a lower incidence of grade 3 or 4 toxic effects than AC group(10.0% vs.25.9%,P =0.041).The 1-year,3-year,and 5-year survival rates in the neoadjuvant chemotherapy group were 97.6%,90.5% and 88.1%,respectively.The 1-year,3-year,and 5-year survival rates in the adjuvant chemotherapy group were 96.4%,77.8%and 68.1%,respectively.The 1-year,3-year and 5-year disease-free survival rates of the n CTgroup were 97.6%,90.5% and 75.1%,respectively,and the non-n CT group’s1-year,3-year and 5-year disease-free survival rates were 85.7%,65.6% and51.3%.However,there was no significant difference between the two groups in overall survivaland disease-free survival(P = 0.206 &P = 0.111).The 5-year cumulative incidence of distal recurrences was 8.9% in neoadjuvant chemotherapy group and 26.2% in adjuvant chemotherapy group.The distal recurrence rate in neoadjuvant chemotherapy group was significantly lower than in adjuvant chemotherapy group(P=0.022).There was no significant difference in the incidence of 5-year local recurrences betweenneoadjuvant chemotherapy and adjuvant chemotherapy groups(17.5% vs.12.8%;P=0.861).Conclusion:Neoadjuvant chemotherapycombined with laparoscopic radical resection is safe and reliable in the treatment of locally advanced colon cancer.Neoadjuvant chemotherapy with laparoscopic radical resection of colon cancerreduces distant recurrence rate and has better tolerance to the toxic effects of chemotherapy compared with direct laparoscopic radical resection in the treatment of locally advanced colon cancer,but it does not show the advantages of reducing local recurrence rateor improving survival rate.