Analysis Of Factors Influencing The Efficacy Of Neoadjuvant Chemoradiotherapy In Rectal Cancer

Background:At present,colorectal cancer(CRC)is the fourth most common cancer in China.Because of the economic development,diet framework,environment and social aging,the incidence rate of colorectal cancer has obviously increased.[2 and 3],and showed an obvious trend of aging.In addition,the incidence of colorectal cancer is higher than that of colon cancer.In the treatment of rectal cancer,preoperative neoadjuvant chemoradiotherapy combined with total mesorectal excision is now the representative treatment mode of locally advanced rectal cancer.However,according to the research of relevant scholars,because the preoperative neoadjuvant therapy takes a long time,usually takes about 3 months,the compliance rate has been very low.In addition,the sensitivity of different patients in the performance of neoadjuvant chemoradiotherapy is quite different,some patients after neoadjuvant chemoradiotherapy can get pathological complete remission,while some patients with rectal tumor is further developed.Therefore,it is of great significance to explore the relationship between the rate of down grading after neoadjuvant therapy and age,gender,tumor location,size,clinical stage before neoadjuvant therapy,and operation interval after neoadjuvant therapy.Objective: To investigate the mechanism of the diseaseThe purpose of this paper is to study the related factors of whether the patients with locally advanced rectal cancer after neoadjuvant therapy are in remission stage.Methods: The clinical data of patients with locally advanced rectal cancer admitted to the second Department of surgery,the fourth hospital of Hebei Medical University from 2014 to 2020 were retrospectively analyzed,and 79 patients who met the inclusion criteria after neoadjuvant treatment were collected.Univariate analysis of variance(ANOVA)and chi square test were used to study the influencing factors of patients with locally advanced rectal cancer after neoadjuvant therapy.Result: A total of 79 patients with locally advanced stage II and III were included in this study.Among them,52 patients(65.8%)reached the stage of decline after neoadjuvant therapy,and 27 patients(36.2%)did not reach the stage of decline.Eight factors were included in this study: gender,age,the distance between the lower pole of the tumor and the anal margin,the length of the tumor,the thickness of the tumor,the ratio of the circumference of the involved bowel,the tumor stage before neoadjuvant therapy,and the operation interval after neoadjuvant therapy.The analysis showed that: Patients with low rectal cancer(P = 0.014),patients with small tumor size(0.018),patients with less than half of the circumference ratio of the bowel(P = 0.041),patients with stage III(i.e.with lymph node metastasis)(0.003)locally advanced rectal cancer were more likely to get the effect of down-stage after neoadjuvant therapy.Conclusions:1.In locally advanced rectal cancer patients,the distance between the lower pole of tumor and the anal margin,the size of tumor loss,the ratio of tumor involved intestinal circumference and lymph node metastasis are the influencing factors of neoadjuvant therapy.2.Whether neoadjuvant therapy can reduce the stage has no significant relationship with gender,age and tumor thickness,but the relationship between the operation interval after neoadjuvant therapy and neoadjuvant concurrent chemotherapy and the stage needs to be further studied.