The Value Of Postoperative Adjuvant Radiotherapy And Prognostic Analysis In Patients With Local Advanced Upper Rectal Cancer

BackgroundColorectal cancer is the most common malignant tumor of the digestive system worldwide.With the rapid development of economy and transformation of society,the incidence and mortality of colorectal cancer in China are on the rise.Due to anatomical location,intestinal microbiota,immune microenvironment,molecular gene expression,etc.,the prognosis and treatment of colon cancer and rectal cancer are not the same.Compared with colon cancer,radiotherapy is more important in the treatment of rectal cancer.Rectal cancer is divided into upper rectal cancer,middle and lower rectal cancer according to tumor location.The prognosis of upper rectal cancers is significantly better than that of middle and lower rectal cancer,which is closer to the prognosis of colon cancer.In recent years,with the promotion and popularization of total mesorectal excision and conformal intensity-modulated radiation therapy,the therapeutic effect of rectal cancer has been further improved,and the local recurrence rate has been significantly reduced.In the era of precise surgical and radiotherapy techniques,the roles of postoperative adjuvant radiotherapy in the upper rectal cancer has been challenged.ObjectiveTo specify whether patients with locally advanced upper rectal cancer could benefit from postoperative adjuvant radiotherapy,and to identify the risk factors affecting the prognosis of patients with upper rectal cancer.MethodsPatients with locally advanced upper rectal cancer after radical surgery from January 2013 to December 2017 in Shandong Provincial Cancer Hospital were enrolled in the retrospective analysis.OS and DFS were compared in patients with postoperative adjuvant radiotherapy and those without adjuvant radiotherapy.Survival analysis was performed to determine the role of clinical factors such as gende^and pathological differentiation to the prognosis of patients with upper rectal cancer.Results1.This study enrolled 123 patients with locally advanced upper rectal cancer.They all xunderwent radical surgery.The median follow-up is 26 months?range:4-67 months?.In the 52 patients receiving postoperative radiotherapy,16?30%?were involved in disease progress and 3?6%?patients died.In the 71 patients not receiving postoperative radiotherapy,23?32%?were involved in disease progress,and 8?12%?died.2.The patients with postoperative radiotherapy had no significantly benefit in OS compared the patients without postoperative radiotherapy?88.3%vs 89.5%,P=0.5557;HR 0.5096,95%CI:0.1541-1.685?.There was no significant difference in 3-year DFS,either?60.3%vs 12.6%,P=0.8925;HR 0.9899,95%CI:0.5233-1.873?.3.Univariate analysis for OS revealed a statistically significant effect for gender?P=0.091?,pathological differentiation?P=0.000?,neurological invasion?P=0.001?,paracancerous nodule?P=0.001?,lymph node metastasis rate?P=0.007?,N stage?P=0₀01?and TNM stage?P=0.003?.Multivariate analysis for OS showed a statistically significant effect for paracancerous nodules and N stage.Univariate analysis for DFS revealed a statistically significant effect for gender?P=0.059?,gross type?P=0.084?,pathological differentiation?P=0.000?,neurological invasion?P= 0.000?,paracancerous nodule?P = 0.000?,lymph node metastasis rate?P= 0.020?,N stage?P = 0.015?and TNM stage?P = 0.008?.Multivariate analysis identified four independent risk factors for DFS:gross type,pathological differentiation,neurological invasion,and paracancerous nodule.3.In the 52 patients receiving postoperative radiotherapy,4?8%?had grade 3 lower gastrointestinal acute radiation injury.Among them,2 patients discontinued radiotherapy,and were finally performed 11 and 13 fractions respectively.No patients had grade 4 lower gastrointestinal acute radiation injury.4.Multivariate analysis indicated that start time of radiotherapy and paracancerous nodules were independent risk factors for DFS in patients receiving radiotherapy.Those patients with radiotherapy delays longer than half a year after surgery had a high risk in disease progression?HR = 6.836,95%CI:2.113-22.118;P=0.001?.Conclusions1.In the era of total mesorectal excision of rectal cancer,some patients with upper rectal cancer could omit postoperative adjuvant radiotherapy.2.In patients with locally advanced upper rectal cancer,paracancerous nodule and N stage are independent prognostic factors for OS.Meanwhile,gross type,pathological differentiation,neurological invasion,and paracancerous nodule are independent risk factors for DFS.3.In the era of conformal intensity-modulated radiotherapy,the treatment in upper rectal cancer leads less radiation damage and most patients are well tolerated to radiotherapy.4.For patients needing postoperative radiotherapy,the time to start radiotherapy should not be delayed longer than six months after surgery...