基于高分辨MRI预测中低位直肠癌根治术后局部复发风险

Predicting the Risk of Local Recurrence after Radical Surgery for Mid-low Rectal Cancer Based on High-Resolution MRI

目的探讨基于高分辨MRI测量直肠周围脂肪含量联合临床及病理因素对中低位直肠癌术后局部复发(local recurrence,LR)的预测价值。方法回顾性分析205例中低位直肠癌患者的临床及术前影像学资料,根据术后是否发生LR将患者分为复发组(n=32)和非复发组(n=173),运用独立样本t检验比较两组患者的直肠周围脂肪含量特征间差异,采用单因素及多因素Cox回归分析方法筛选患者术后LR的独立危险因素。结果独立样本t检验比较结果显示,复发组患者的直肠系膜脂肪面积(mesenteric fat area,MFA)、直肠后系膜厚度(posterior mesorectal thickness,PMT)及直肠系膜筋膜包裹体积(mesenteric fascia envelopment volume,MFEV)均小于非复发组(P均<0.05)。根据单因素Cox分析结果显示,术前糖类抗原199(CA19-9)、肿瘤病理T分期、N分期、mrN分期、肿瘤是否侵犯周围结构、MFA、PMT、MFEV均与术后局部复发相关(P均<0.05)。多因素Cox分析结果表明,肿瘤病理N分期(P=0.001)、肿瘤是否侵犯周围结构(P=0.000001)、PMT(P=0.038)均可独立预测中低位直肠癌术后LR。结论肿瘤病理N1及N2期、肿瘤侵犯周围结构、PMT为术后LR的独立危险因素,有望成为预测中低位直肠癌根治术后复发的有效生物标志物。

Objective To investigate the predictive value of measuring perirectal fat content based on high-resolution MRI in combination with clinical and pathological factors for predicting local recurrence(LR)after surgery for mid-low rectal cancer.Methods A retrospective analysis of clinical and preoperative imaging data from 205 patients with mid-low rectal cancer was conducted.Patients were divided into a recurrence group(n=32)and a non-recurrence group(n=173)based on whether LR occurred after surgery.Independent sample t-tests were used to compare differences in perirectal fat content characteristics between the two groups.Univariate and multivariate Cox regression analysis methods were used to identify independent risk factors for postoperative LR in patients.Results The results of independent sample t-tests showed that patients in the recurrence group had smaller mesenteric fat area(MFA),posterior mesorectal thickness(PMT),and mesenteric fascia envelopment volume(MFEV)compared to the non-recurrence group(all P<0.05).According to the results of univariate Cox analysis,preoperative CA19-9,tumor pathological T stage,N stage,mrN stage,tumor invasion of surrounding structures,MFA,PMT,and MFEV were all associated with postoperative LR(all P<0.05).The results of multivariate Cox analysis indicated that tumor pathological N stage(P=0.001),tumor invasion of surrounding structures(P=0.000001),and PMT(P=0.038)could independently predict LR after surgery for mid-low rectal cancer.Conclusion Tumor pathological N1-2 stage,tumor invasion of surrounding structures,and smaller PMT are independent risk factors for LR after surgery for mid-low rectal cancer,and may serve as effective biomarkers for predicting postoperative recurrence.