Application Of Pull-through Conformal Resection In Low Rectal Cancer And The Analysis Of Related Factors

Pull-through conformal resection(PTCR) is an ultimate sphincter preservation surgery based on modern colorectal theory and developed technology. We analyze and compare the clinical pathology characteristics of the patients undergo the PTCR、LAR or APR to provide theoretical support for PTCR.Objective: 1. To investigate the safe distant resection margin for low rectal cancer and evaluate wether the DRM<1cm is safe for the formalin-fixed specimen. 2. Analyze the clinical pathology characteristics of the patients undergo the PTCR、LAR or APR,to compare the advantages and disadvantages of these three surgery.To evaluate the anal control and bowel function of PTCR through the follow up.3. Analyze the risk factors associate with lymph node metastasis of T1、T2a and T2 b rectal cancer to evaluate the indications of PTCR for low rectal cancer patients.Methods: 1.From January 1999 to December 2009 a total of 286 patients with rectal cancer who underwent curative resection in changhai hospital were enrolled in this study. The situations of local recurrence, distant metastasis and survival of the three group(DRM≤0.5cm,0.5<DRM≤1cm,DRM>1cm) were analyzed retrospectively.2. From January 2010 to December 2013 a total of 228 patients with rectal cancer who underwent PTCR,APR or LAR in changhai hospital were enrolled in this study. The clinicopathological factors and the follow-up datas were analyzed retrospectively.3. From January 1999 to December 2013 a total of 576 patients with rectal cancer who underwent curative resection in changhai hospital were enrolled in this study. The relationship between clinicopathological factors and lymph node metastasis was analyzed retrospectively.Results:1. The local recurrence rate(P = 0.158), distant metastasis rate(P = 0.999), five-year overall survival(P = 0.394), five-year disease-free survival(P = 0.621) of three groups of patients have no significance. Deeper infiltrating, poorer differentiated, lymph node metastasis, CEA>5(ng/ml) and CA199>37(U/ml) were risk factors affecting patient survival. Lymph node metastasis and CEA>5(ng/ml) were risk factors affecting local recurrence. Factors for postoperative metastasis were gender, lymph node metastasis, and CA199>37U/ml.2. The age, sex ratio, whether neoadjuvant therapy before the surgery, the number of lymph nodes and M stage of three groups of patients detected no significance. The distance from the anal tumor,PTCR and APR were significantly less than the LAR(P <0.001). Blood loss, operative time and postoperative hospital stay PTCR,LAR have no significance, and were less than APR(P = 0.007, P <0.001, P = 0.009). The PTCR in tumor differentiation, T stage, N stage was significantly better than the LAR group and APR group(P = 0.004, P = 0.004, P = 0.003). Distant resection margin, PTCR group also significantly less than LAR group(P <0.001). The local recurrence rate LAR, PTCR and APR were 2.38%, 3.45%, 5.47%, which have no significance(P = 0.517) between the three groups. The daily average number of bowel movements after surgery(P = 0.662), Wexner score(P = 0.245), then rate of satisfactory fecal continence(P = 0.785) were not statistically different. 3. The overall rate of lymph node metastasis was 20.3%(T1:9.7%; T2a:22.0%; T2b:23.4%). Single factor and multi factor analysis showed: tumor differentiation(OR=1.54, P=0.007), preoperative peripheral blood CA199 level(OR=2.14, P=0.012), gross pathology type(OR=1.60, P=0.024), depth of invasion(OR=2.08,P=0.021) were independent risk factors of lymph node metastasis.Conclusion:1. To ensure distant resection margin negatively, the DRM will not affect postoperative local recurrence,rate of distant metastasis and 5-year over-all survival rate. 2. PTCR in the case of selecting the appropriate patients is safe and feasible. But this study is relatively small number of cases of treatment and the follow-up time is not long enough, so we need to continue to observe the long-term follow-up results of oncology. 3. Tumor differentiation, concentration of CA199, gross pathology type, depth of invasion(mucosa or muscularis propria) but not the muscularis propria infiltration levels(circular muscle or longitudinal muscle) were risk factors for lymph node metastasis in patients with T1, T2 a,T2b stage rectal cancer.