Cancer Neoadjuvant Treatment And Transfer Of Related Genes

Objective:To verify the accuracy of endoscopic ultrasonography(EUS) in restaging rectal cancer after neoadjuvant therapy,evaluate the efficacy of neoadjuvant therapy on locally advanced rectal cancer,and study the features of expression and correlation between VEGF and CTHRCl in rectal cancer.Methods:Sixty-one patients with T₃/T₄ tumors located in less than 12cm from the anal verge,without distant metastases according to clinical staging were adimitted to neoadjuvant therapy.Surgery was performed after 2 to 4 weeks following completion the therapy under the rule of total mesorectal excision for curative resection.EUS staging was used before and after neoadjuvant therapy in all patients,and the results were compared with the pathologic staging.The expression of VEGF and CTHRCl were tested by immunohistochemistry in another 98 patients of rectal cancer.Results:Sixty-one patients were enrolled in our study.After neoadjuvant therapy,all of them were perfromed curative resection,including Dixon in 59 patients and Miles in 2 patients.The overall sphincter preservation was 96.72%and the complete response rate was 3.28%.The pathologic staging was decreased in 93.44%of the patients after neoadjuvant therapy.Follow-up was taken in all patients.Liver metastases occurred in one patient.After chemoradiation,the total accuracy for T staging by EUS was 59%and the accuracy for N-stage by EUS was 68.9%.VEGF was distributed mainly in the tumor cells,and its expression was correlated with the clinical stages,tumor differentiation and lymph metastasis,statistically(P＜0.05).The expression of CTRHCl was related with the clinical stages and tumor differentiation (P＜0.05),both of them have no correlation with age and gender of patients.Moreover, a positive correlation was showed between VEGF and CTHRCI by correlative analysis(r=0.629,P＜0.001). Conclusion:Neoadjuvant therapy is highly effective and safe.Down-staging occurred in most of patients.Preoperative radiochemotherapy significantly increased curative respectability and sphincter preservation,with an apparent improvement in local control and overall long-term survival.The accuracy of EUS restaging rectal cancer after neoadjuvant therapy is decreased.There are higher expression of VEGF and CTHRCl in rectal cancer,and both of them may play important roles in invasion and metastasis in rectal cancer.The two biomarkers may be applied to assess the malignancy of rectal cancer.