Risk factor analysis of low anterior resection syndrome after anal sphincter preserving surgery for rectal carcinoma

目的 探索直肠癌保肛手术后患者低位前切除综合征(LARS)的相关危险因素.方法 选取2010年1月至2014年6月在北京大学人民医院胃肠外科接受保肛手术患者的临床病理学资料进行回顾性分析,排除永久造瘘和局部切除者.并于2014年10月至2015年3月,对入选患者采用专为LARS设计的量表通过面对面访谈或电话询问方式,按照手术先后顺序依次进行随访.根据调查量表得分情况(0~20分为"无LARS",21~29分为"轻度LARS",30~42分为"重度LARS")将患者按照LARS轻重程度分为3组,比较每组患者的人口学和临床病理学资料,并采用Logistic回归分析重度LARS的发病相关危险因素.结果 共有100例患者完成调查,男性61例,女性39例,接受手术时平均年龄66.2(41~86)岁,其中年龄<60岁与≥60岁者分别为33例和67例,未观察到年龄分布的差异(P=0.204).自手术日至随访日间隔时间超过1年者70例,中位随访间隔23月.其中无LARS组37例,轻度LARS组18例,重度LARS组45例.3组临床病理学资料的比较,除有无放疗史(P=0.025)、肿瘤位置(P=0.000)和吻合口距肛缘距离(P=0.008)差异有统计学意义外,其余差异均无统计学意义(均P>0.05).将无LARS和轻度LARS组合并后与重度LARS组进行重度LARS发病危险因素分析结果显示,有无放疗史(RR:5.608,95%CI:1.457~21.584,P=0.006)、肿瘤下缘距离(RR:0.125,95%CI:0.042~0.372,P=0.000)、吻合口距肛缘距离(RR:0.255,95%CI:0.098~0.665,P=0.004)以及回肠造口与否(RR:3.643,95%CI:1.058~12.548,P=0.032)与重度LARS有关;潜在的危险因素为女性患者(RR:2.138,95%CI:0.944~4.844,P=0.078).多因素分析结果显示,女性(RR:2.654,95%CI:1.005~7.014,P=0.049)、放疗史(RR:10.422,95%CI:2.394~45.368,P=0.002)和肿瘤下缘距离≤7 cm(RR:8.935,95%CI:2.827~28.243,P=0.000)是发生重度LARS症状的独立危险因素.结论 直肠癌保肛术后患者发生LARS较为普遍.女性、放疗和低位肿瘤患者行保肛术会增加发生重度LARS的风险,对这类患者行保肛术应注意采取预防措施.Objecive To investigate the risk factors of low anterior resection syndrome (LARS) after anal sphincter preserving surgery (SPS) for rectal cancer patients. Methods Clinicopathological and follow-up data of rectal cancer patients who underwent SPS from January 2010 to June 2014 in Department of Gastroenterological Surgery, Peking University People' s Hospital, were retrospectively analyzed. Patients receiving permanent colostomy and local resection were excluded. Meanwhile, during October 2014 and March 2015, the enrolled patients were asked to fill out a specially designed questionnaire for LARS through face-to-face interview or telephone inquiry, according to the chronological order of operation. Based on the score of questionnaire, patients were divided into three groups: 0-20 points: non LARS; 21-29: minor LARS; 30-42: major LARS. The demographic and clinicopathologic features were compared among groups and the risk factors of major LARS were tested by logistic regression analysis. Results A total of 100 patients (61 males, 39 females) completed the bowel function survey, with an average age of 66.2 (41-86) years, 33 patients < 60 years versus 67 patients≥60 years. No significant difference was observed in age distribution (P=0.204). Interval from operation to first follow-up was more than 1 year in 70 patients, and the median follow-up was 23 months. Thirty-seven patients were non LARS, 18 were minor LARS and 45 were major LARS. No significant differences in clinicopathological data (all P> 0.05) were observed among three groups except radiotherapy history (P=0.025), tumor location (P=0.000) and distance from anastomotic site to anal verge(P=0.008). After comparison of non LARS group combined with minor LARS group versus major LARS, re-analysis of risk factors showed that radiotherapy history (RR=5.608, 95%CI:1.457 to 21.584, P=0.006), distance from tumor lower margin to anal verge (RR=0.125, 95%CI: 0.042 to 0.372, P=0.000), distance from anastomotic site to anal verge (RR=0.255, 95%CI: 0.098 to 0.665, P=0.004) and preventive ileostomy history (RR=3.643, 95%CI:1.058 to 12.548, P=0.032) were associated with major LARS. One potential risk factor detected in combined analysis was female (RR=2.138, 95%CI: 0.944 to 4.844, P=0.078). Multivariate analysis revealed that female (RR=2.654, 95%CI:1.005 to 7.014, P=0.049), radiotherapy history (RR=10.422, 95%CI:2.394 to 45.368, P=0.002) and distance from tumor lower margin to anal verge ≤ 7 cm (RR = 8.935, 95%CI:2.827 to 28.243, P=0.000) were independent risk factors of major LARS. Comclusioms LARS is a significant problem in most rectal cancer patients after SPS. The risk of major LARS increases on condition of radiotherapy, low tumor position and female. When dealing with these patients, preventive measures should be taken into consideration during SPS.教育部高等学校博士学科点专项科研基金资助项目(2109000069)The ministry of education by the specialized research fund for the doctoral program of higher education project中国科学引文数据库(CSCD)3289-2942