中文摘要：

目的 了解直肠癌术前VMAT同期化疗后肠壁残余癌细胞分布及关联因素.方法 搜集2011-2013年间本院术前VMAT同期化疗＋手术的178例直肠癌患者资料,其中男124例、女54例,年龄23 ～ 84岁;T1、T2、T3、T4期分别为l、2、73、102例.对所有手术标本肠壁残余癌细胞行病理评价.对各组间差异行Fisher＇s精确概率法检验,对临床T、N分期与ypT期及残余癌细胞分布的相关性行Spearman等级相关分析.结果 术后切除标本肠壁黏膜层、黏膜下层、固有肌层、浆膜层或外膜层残余癌细胞比例全组患者分别为15.2％、27.0％ 、46.6％、46.1％,120例ypT2～4期患者的分别为20.0％、36.7％、69.2％、68.3％.术后52例ypT0期、2例ypTis期、4例ypT1期、38例ypT2期、77例ypT3期、5例ypT4期.36例ypN（＋）期中ypT0期的比例低于140例ypN0期的（3％∶35.7％,P=0.000）,但其浆膜层或外膜层残存癌细胞比例远高于ypN0期的（83％∶36.4％,P=0.000）.73例T3期中ypT0期的比例高于102例T4期的（37％∶21.6％,P=0.025）.结论 VMAT同期化疗后肠壁残余癌细胞大部分位于固有肌层及以下,与ypT、ypN、T分期显著关联;但VMAT同期化疗后直肠原发病灶活检的临床价值可能有限.

英文摘要：

Objective To investigate the distribution of residual cancer cells （RCCs） in the bowel wall and its associated factors among patients with rectal cancer after preoperative volumetric modulated arc therapy （VMAT） with concurrent chemotherapy.Methods A retrospective analysis was performed on the clinical data of 178 patients with locally advanced rectal cancer who received VMAT with concurrent chemotherapy followed by surgery in our hospital from April 2011 to April 2013.There were 124 males and 54 females,and the age range was from 23 to 84 years.T1,T2,T3,and T4 rectal cancer was found in 1,2,73,and 102 patients,respectively.All the RCCs in surgical specimens from different layers of the bowel wall were evaluated pathologically.Between-group differences were evaluated by Fisher＇s exact test,and the associations of preoperative T and N stages with postoperative ypT and distribution of RCCs in the bowel wall were determined by Spearman rank correlation test.Results The rates of RCCs in the mucosa,submucosa,muscularis propria,and subserosa/perirectal fat surgical specimens were 15.2%,27.0%,46.6%,and 46.1%,respectively,for all patients,and were 20.0%,36.7%,69.2%,and 68.3%,respectively,for 120 patients with ypT2-4 disease.Of all patients surgically treated,52 had ypT0 disease,2 had ypTis disease,4 had ypT1 disease,38 had ypT2 disease,77 had ypT3 disease,and 5 had ypT4 disease.The rate of ypT0 in 36 ypN （＋） patients was significantly lower than that in 140 ypN0 patients （3% vs.35.7%,P =0.000）,yet its rate of RCCs in the subserosa/perirectal fat was significantly higher than that in ypN0 patients （83% vs.36.4%,P =0.000）.The rate of ypT0 was significantly higher in 73 T3 patients than in 102 T4 patients （37% vs.21.6%,P =0.025）.Conclusions Most RCCs in the bowel wall of patients treated with preoperative VMAT with concurrent chemotherapy are distributed within or below the muscularis propria,which are significantly associated with ypT,ypN,and T stages.The value of biopsy for primary rectal lesio