Comparative Study Of Neoadjuvant Chemotherapy And Neoadjuvant Chemoradiotherapy Clinical Efficacy On Mid-set And Low-set Locally Advanced Rectal Cancer

Objective (s):Through retrospective comparative study of neoadjuvant chemoth erapy group and neoadjuvant chemoradiotherapy group of cT3-4/N+mid-set a nd low-set locally advanced rectal cancer patients, we intend to observe the sh ort-term efficacy and clinical feasibility of neoadjuvant chemotherapy of mid-set and low-set locally advanced rectal cancer.Methods:Collecting clinical data of 46 mid-set and low-set locally advanced rectal cancer patients from January 2013 to December 2015, we divided them i nto 2 groups:neoadjuvant chemotherapy(NCT) group and neoadjuvant chemora diotherapy(NCRT) group,23 for each.For NCT group patients recieved 4 cycles preoperative chemotherapy of mFOLFOX6 or XELOX first andthen,after preop erotive analysis they received operation.For NCRT, patients recieved preoperativ e3 fields radiotherapy(45-50Gy/25-28 times) accompanied with Capecitabine che motherapy(825mg/m2, twice a day)and after 5-12 weeks of intermission(8 wee ks generally) with or without chemotherapy they recieved operation. We intend to observe the clinical remission rate (RR), degrading rate of T and M, turn or regression grading(TRG),DFS,OS and recurrence rate.Results:1 After recieving neoadjuvant therapy, tumors of both teams regress obviously,NCRT group vs. NCT group(38% vs.28%,p>0.05); there is no statist ical differences in regression rate remission rate,NCRT group vs. NCT group(52. 2% vs.34.8%,p>0.05).2 For NCRT group, degrading rate of T is 60.9%, which is higher than NCT team of 30.4%, without any statistical differences; degrading rate of N is 85.7 %, which is higher than NCT team of 75%,without any statistical differences.3 The number of complete pathological regression (TRGO)is 4 for NCRT and 1 for NCT,without statistical differences;the number of moderate pathological re gression(TRG1) is 10 for NCRT and 3 for NCT,p-0.026; mild pathological regr ession(TRG2) is 6 for NCRT and 12 for NCT,p=0.047.4 The DFS of NCRT is 77.3%, which is low than NCT of 95.5%,and the O 5 of both teams is 95.7%, without any statistical differences,and during the fo llow-up the death toll of each team is 1. During the follow-up, there is no pat ients of recurrence in NCT,while there is 5 patients of recurrence(3 patients of pelvic or anastomotic recurrence).5 Grade≥3 blood system adverse events, NRCT group 8.7%higher than the NCT group 0%, P=0.47;Intestinal obstruction NRCT 8.7% higher than the N CT group 8.7%, P=0.55;Anastomotic bleeding NRCT 6.7% below the NCT g roup 14.3%, P=0.473;Anastomotic fistula NRCT 13.3% higher than the NCT group 9.5%, P=0.72;Preventive colostomy NRCT 80% higher than the NCT group 19%, P< 0.001).6 In T3 subgroup, there is no statistical differences of degrading rate in T3c o f both groups.The number of TRG1 is 5 in NCRT(71.4%)and 2 in NCT (18.2 %);the DFS is 71.43% in NCRT and 100% in NCT; the OS is 87.5% in NCR T and 100% in NRT,without statistical differences. There is no recurrence in N CT and 2 recurrence in NCRT.Conclusion(s):1 Both of neoadjuvant chemotherapy and neoadjuvant chemoradi otherapy will achieve degrading and regression effect of tumors in treatment of mid-set and low-set locally advanced rectal cancer.2 NCRT achieves more in pathological regression grading than NCT,especially in TRG0 and TRG1.3 There are no statistical differences in OS of both groups, but for the fact th at DFS of NCT is 95.5% which is higher than NCRT of 77.3%,that makes a 1 ittle sense in recurrence and metastasis treatment.4 There are no statistical differences of side effect rate in both groups, but the preventive neostomy rate is low in NCRT.5 In T3c subgroup analysis, NCRT achieves more in pathological regression gr ading than NCT, in DFS NCT is higher than NCRT group, without statistical differences.