Analysis Of Related Factors Of Pathological Complete Response After Neoadjuvant Therapy For Locally Advanced Rectal Cancer

Objective: There are individual differences in the efficacy of neoadjuvant therapy for locally advanced rectal cancer.Some patients may achieve clinical complete response(cCR)or even pathological complete response(pCR).This study aims to explore and analyze the related clinical factors affecting pCR after neoadjuvant therapy for locally advanced rectal cancer in order to better guide the follow-up individualized therapy.Subjects and Methods: A retrospective analysis of 79 cases of rectal cancer patients admitted to the Department of Colorectal and Anal Surgery,the First Affiliated Hospital of Guangxi Medical University from January 2013 to March2019.All patients underwent neoadjuvant therapy before surgery.Be operated on by 4~8 weeks after treatment,at the latest 12 weeks.Univariate analysis and Logistic multivariate regression analysis were used to study the related clinical factors affecting postoperative pCR.Results: Seventeen patients(17/79,21.5%)achieved pCR after neoadjuvant therapy.Univariate analysis showed that serum CEA levels(P=0.004)and circumferential resection margin(CRM)(P=0.016)before neoadjuvant therapywas associated with pCR rates after neoadjuvant therapy for rectal cancer.Multivariate regression analysis showed that CEA levels(OR=1.830,P=0.007),tumor T stage(OR=0.013,P=0.003),N stage(OR=26.442,P=0.015),CRM(OR=41.180,P=0.008),and maximum tumor diameter(OR=5.708,P=0.09)before neoadjuvant therapy were the important factors affecting pCR after neoadjuvant chemoradiotherapy for locally advanced rectal cancer.Conclusion: The clinical factors before neoadjuvant therapy such as low CEA level,low T,N stage and negative CRM and maximum tumor diameter(<5cm)may be important factors for obtaining pCR,which may be helpful to predict pCR after neoadjuvant therapy for locally advanced rectal cancer.