直肠癌局部浸润3.0 T磁共振征象与病理学T分期的对照研究

目的:探讨直肠癌局部浸润的MRI征象与病理T分期的关系.材料和方法:经病理证实的62例直肠癌患者,术前接受MR检查.使用3.0T MRI对直肠癌局部浸润征象进行分析、归类、做出分期诊断,并与术后病理组织学肿瘤T分期进行对照.结果:62例直肠癌MRI T分期总的诊断准确性为77.4%,≤T2~T4期MRI诊断准确性分别为88.71%、77.42%和88.71%.直肠癌局部浸润的MRI征象与病理T分期间相关性较强(r= 0.725,P<0.001).直肠癌侵犯肠周径程度与病理T分期呈中等正相关(r= 0.699,P<0.001).结论:MRI征象的正确识别和肿瘤对肠管周径侵犯程度的评价对直肠癌T分期诊断有一定帮助.体外相控阵线圈3.0T MRI技术可较准确地显示直肠癌的T分期,有助于计划手术方案以确保对病灶的完整切除,降低复发率.     

薄层MRI直肠癌T3期征象与病理对照研究

目的 探讨薄层MRI直肠癌T分期征象对直肠癌术前分期价值.方法 58例患者行薄层MRI,由两位高年资诊断医师进行T分期及征象评估,最终结果与病理结果对照研究.结果 薄层MRI T分期与病理结果一致性好,Kappa值0.82.直肠癌MRI T分期各级征象与病理分期呈正向线性相关,相关性强(rs =0.874,P＜0.01).壁外索条影、肌层信号中断、肿瘤结节样外凸、系膜脂肪间隙模糊等征象对T3期的准确性分别为67.2％、93.1％、84.5％、72.4％;敏感性分别为64.5％、93.5％、70.9％、77.4％;特异性分别为70.4％、92.6％、100％、66.7％.结论 薄层MRI直肠癌T分期征象用于直肠癌术前T分期有一定的价值.     

MRI常规序列结合DWI对盆腔内结直肠癌术前临床分期的价值

目的 :探讨MRI常规序列结合DWI对盆腔内结直肠癌术前T-N分期的价值。方法 :53例经病理证实结直肠癌患者,术前对其行MRI常规序列及DWI检查。并根据AJCC 2010版癌症分期手册制订影像学分期标准,进行术前T分期和局部N分期,与术后病理T分期(pathological T stages,p T)和局部的N分期(pathological N stages,p N)比较。结果:MRI对p T1~2期的诊断准确率88.7%,p T3期83.0%,p T4期94.3%,对T分期总诊断准确率83.0%,与病理分期一致性好(K=0.582,P0.01)。MRI对N分期诊断准确率81.1%,特异性89.2%,敏感性62.5%,阳性预测值71.4%,阴性预测值84.6%,与病理分期一致性好(K=0.536,P0.001)。结论:MRI常规序列结合DWI对盆腔内结直肠癌术前T-N分期具有重要价值。     

薄层MRI联合MR扩散加权成像对直肠癌术前局部分期的价值

目的 以病理分期作为金标准,探讨薄层MRI联合MR扩散加权成像(DWI)对直肠癌术前局部分期的价值.资料与方法 对首诊直肠癌的40例患者进行前瞻性研究.40例均行常规MRI、薄层MRI和DWI后手术治疗并行病理分期.结果 薄层MRI较常规MRI能更好地显示肠壁的各层解剖结构及肿瘤对肠壁及邻近结构的侵犯范围和程度.常规MRI、薄层MRI联合DWI两种检查方法行IN分期的准确性分别为45％和67.5％,差异有统计学意义(P =0.044);T分期的准确性分别为65％和85％,差异有统计学意义(P=0.040);N分期的准确性分别为65％和75％,差异无统计学意义(P=0.332).结论 薄层MRI联合DWI在直肠癌术前局部分期(TN分期)方面优于常规MRI,特别是在T分期方面,薄层MRI联合DWI更具优势,准确性提高到85％;在N分期方面,薄层MRI联合DWI与常规MRI相比无明显差别.     

3.0T MRI平扫联合DWI在直肠癌诊断分期中的应用价值

目的分析3.0T磁共振平扫联合扩散加权成像在直肠癌分期诊断中使用价值。方法选取我院2018年2月～2019年10月经病理诊断为直肠癌的患者40例,术前均使用3.0T磁共振平扫联合DWI扫描,对图像进行分析,评估病变的临床分期。结果 3.0T HR-MRI T_2WI、DWI扫描T期诊断准确率为95.00%(38/40),T1期灵敏度准确度66.67%、T2期50.00%、T3期100.00%、T4期100.00%;在40例直肠癌患者之中,3.0T磁共振平扫、扩散加权成像诊断出36例,准确率90.00%,其N0期准确率为92.00%、N1期81.82%、N2期100.00%。结论 3.0T MRI平扫联合DWI,在直肠癌诊断分期中准确率较高,有助于临床手术评估及治疗的选择。     

动态增强MRI在中下段直肠癌T3分期中的应用研究

目的探讨动态增强 MRI 在中下段直肠癌 T3分期中的价值.方法本研究共纳入84例中下段直肠癌病人,包括经病理证实为 T3期直肠癌的66例.所有病人术前均接受动态增强 MRI 检查.分析 T3期直肠癌局部浸润的 MRI 征象,进行影像-病理对照,计算动态增强 MRI 诊断 T3分期的准确度、敏感度、特异度、阳性预测值和阴性预测值.对直肠系膜内癌性与非癌性索条影在边缘和强化形式上的差异进行统计学分析.结果 MRI 对中下段直肠癌 T3分期的诊断准确度、敏感度、特异度、阳性预测值和阴性预测值分别为86.90%、90.91%、72.22%、92.31%和68.42%.直肠系膜内癌性与非癌性索条影在边缘和强化形式上的差异均有统计学意义(P<0.05).在判断 T3期直肠癌局部浸润深度时,将直肠系膜内癌性索条影误判为非癌性索条影是导致分期不足的主要原因.结论通过分析直肠系膜内异常索条影的边缘及强化形式有助于提高中下段直肠癌 T3分期的准确性.     

直肠癌T分期高分辨MRI技术应用及其病理对照研究

目的:探讨高分辨磁共振成像(HR-MRI)TSE T2WI在直肠癌术前T分期中的临床应用价值.方法:67例经病理证实的直肠癌患者行MRI检查.常规行横断面及矢状面TSE T2WI,斜横断面T2WI HR-MRI检查,并将MRI检查结果与手术病理结果进行对照分析.结果:MRI判断直肠癌T分期总的诊断符合率为85.1%,MRI判断≤T2期直肠癌的敏感度、特异度及诊断符合率分别为70%、97.9%和89.6%,T3期分别为90.5%、76%和85.1%,而T4期分别为100%、95.2%和95.5%.结论:HR-MRI能较准确地对直肠癌进行术前分期,有助于术前手术和治疗方案的制定.     

3.0T MRI在直肠癌术前评估中的应用研究

目的 探讨3.0T MRI在直肠癌术前评估中的应用价值.方法 对41例经病理活检证实为直肠癌的患者进行常规MRI、高分辨MRI及扩散加权成像(DWI)扫描,测量肿瘤最下缘离肛缘的距离及累及环周百分比,评估肿瘤的TN分期、环周切缘(CRM)、系膜血管受侵(EMVI)的状态,与肠镜和手术结果比较.结果 MRI对判断肿瘤下缘距肛缘的距离具有很好的预测价值(P>0.05);T1~T2期、T3期肿瘤累及环周百分比的平均值分别是61%、83%(P>0.05);T、N分期诊断的总准确率分别为80.5%、75.6%,与病理诊断的一致性较好(Kappa值=0.564、0.634);CRM、EMVI诊断的总准确性分别是90.2%、73.2%,与病理诊断的一致性分别是较好、中度一致(Kappa值=0.765、0.461).     

MRI在直肠癌术前T分期中的误判分析

目的:探讨MRI在直肠癌术前T分期中的常见误判原因。方法:选择32例经手术病理证实的直肠癌患者,术前均行MRI检查,MRI序列包括常规T1WI、T2WI及STIR。分析直肠癌患者MRI分期,并对照患者术后病理学分期,评估其一致性。结果:直肠癌的术前MRI分期与术后病理学分期的一致性较好(Kappa=0.64,P<0.001)。MRI术前分期误判率为25%,其中,4例pT2期(病理分期为T2期)过度分期为T3期;3例pT3期(病理分期为T3期)低分期为T2期,1例pT3期过度分期为T4期。结论:在直肠癌MRI术前T分期中,正确认识常见误判原因有利于临床治疗方案的制定。     

全身磁共振背景抑制扩散成像在直肠癌术前分期中的应用价值

目的探讨全身磁共振背景抑制扩散加权成像(DWIBS)对直肠癌术前分期的应用价值。资料与方法对39例经肠镜证实的直肠癌患者,术前行全身磁共振DWIBS检查,以直肠癌原发灶病理结果为标准将本组资料分为T2、T3、T4三组,分析原发灶DWIBS上肿瘤信号强度、表观扩散系数(ADC)值、肠壁病变厚度、肠壁受累长度、肿瘤侵犯肠周径的情况五个指标在各组间的差异,及其与T分期的相关性。通过全身DWIBS图像作出术前NM分期,然后与术后NM病理分期结果进行对照,判断DWIBS对直肠癌NM分期的准确性、特异性及敏感性。结果全身DWIBS对直肠癌原发灶检出的敏感性为100%,准确性为100%,DWIBS上所显示的肠壁病变厚度和肠周径侵犯程度在各分期间有显著差异(P<0.05),且两者与T分期均有显著相关性(rs=0.427,P<0.05;rs=0.384,P<0.05);原发灶肿瘤信号强度、ADC值、肠壁受累长度在各分期间均无显著差异(P>0.05)。DWIBS对N分期诊断的总体准确性为84.61%;对N0期诊断的敏感性为85.71%,特异性为83.33%,N1期诊断的敏感性为70.00%,特异性为89.66%,N2期诊断的敏感性为100%,特异性为80.65%。对M期诊断的敏感性及准确性均为100%。结论全身DWIBS对直肠癌NM分期的诊断敏感性较高,是显示转移性淋巴结及远处转移病灶的一种有效检查方法。全身DWIBS对直肠癌原发灶检出的准确性及敏感性很高,但在T分期中的应用有一定的限度,结合常规MRI序列有助于提高T分期的准确性。     

MR-endoscopic US correlation for loco-regional staging of rectal carcinoma

INTRODUCTION: To correlate findings at high-resolution MR and endoscopic US (EUS) for preoperative loco-regional staging of rectal carcinoma. PATIENTS AND METHODS: Fifty-two patients with rectal carcinoma underwent high-resolution MR imaging. Only 43 of these patients underwent EUS due to technical limitations and stenosing carcinomas. Morphological imaging features and TNM staging were evaluated for both imaging modalities. The degree of correlation and accuracy were calculated for both. RESULTS: The correlation between MR and EUS was good for tumor length and thickness (r=0.7 and 0.61) for for nodal (N) staging (k=0.53). Correlation was good for T1 and T2 stages (k=0.51) and T3 stage (k=0.43) and very poor for stage 4 (k= -0.09), because no T4 lesion was detected at EUS. 81.8% of patients where T stage was over-estimated on MRI and 100% of patients where T stage was over-estimated on EUS had received preoperative radiation therapy. Therefore, results should be interpreted with caution. The predictive evaluation of tumor resectability (absence of perirectal fascia invasion) with a circumferential margin on MR> or =5 mm was 93%. CONCLUSION: Correlation between MR and EUS was moderate for T staging, because of limitations of EUS for large tumors. Results confirm that high-resolution MRI is useful for loco-regional staging of rectal carcinoma, especially for large tumors. EUS should be limited to the valuation of superficial tumors of the rectum.     

Endorectal coil MRI in local staging of rectal cancer

PURPOSE: The choice of the therapeutic strategies in patients affected with rectal cancer is strictly dependent by the tumor stage. So, in order to obtain an improvement in preoperative staging accuracy, new imaging modalities are now under investigation. The aim of this work is the evaluation of endorectal-coil MRI in the local staging of rectal cancer. MATERIAL AND METHODS: Fourty-three patients affected with histologically proven rectal cancer, have been evaluated by an high-field strength magnet (1.5 T). In 14/43 patients neoadjuvant pre-operative chemotherapy had been previously performed. In all cases axial SE T1w and FSE T2w sequences and coronal or sagittal FSE T2w sequences, with and without fat suppression, were performed. Basing upon the TNM staging system and the previously reported MRI signs the local extent of the tumor was evaluated, focusing about the rectal wall infiltration and the perirectal lymph nodes involvement. All the patients underwent surgery and a comparative evaluation of MRI and pathological staging was done. RESULTS: At MRI the tumor was detected in 38/43 patients. In evaluating wall infiltration the MRI results agreed with pathological results in 89% of patients and showed 92% accuracy in T1-T2 stage and 94% in T3. In evaluating perirectal lymph nodes metastases MRI showed 69% accuracy, 82% sensitivity and 55%specificity. DISCUSSION AND CONCLUSIONS: The poor accuracy of CT and body-coil MRI in evaluating wall involvement in patients with rectal cancer is mainly related to their inability to demonstrate the single layers of the rectal wall. So transrectal ultrasound is now the first choice modalitiy in local staging of rectal cancer. However transrectal ultrasound showed low sensitivity in detecting perirectal lymph nodes metastases and low accuracy in evaluating the patients previously undergone to neoadjuvant chemotherapy or radiotherapy. On the other hand the improvement of MRI sequences and the availability of the endorectal coils allowed to visualize the single layers of the rectal wall so making the endorectal-coil MRI a reliable imaging technique to stage rectal cancer. The results of our work demonstrate a good diagnostic accuracy of endorectal-coil MRI in local staging of rectal cancer, in particular the degree of rectal wall infiltration was well demonstrated, while the perirectal lymph nodes metastases were demonstrated with less accuracy. The long examination time, the costs and the movement-related artefacts are the main limits of MRI. In particular the movement-related artifacts sometime do not allow the visualization of the wall layers so lowering the diagnostic accuracy in demonstrating the tumor wall infiltration. In conclusion, even though endorectal coil MRI proved to be a reliable imaging technique in local staging of rectal cancer, at present we are not able to state what may be its real role in diagnostic evaluation of the patients with rectal cancer, in particular if compared to endorectal ultrasound. Further, comparative studies, based upon larger patients series are probably needed to draw a definitive conclusion.     

Magnetic resonance with endorectal coil in the local staging of prostatic carcinoma. Comparison with histologic macrosections in 40 cases]

PURPOSE: Endorectal coil MRI is widely used in the diagnostic workup of prostate cancer, but diagnostic accuracy rates reported in the literature are quite variable. We report our personal experience with endorectal coil MRI in the local staging of prostate carcinoma. MATERIAL AND METHODS: Forty consecutive patients with histologically proved prostate carcinoma were examined with endorectal coil MRI at high field strength (1.5 T). All patients underwent a sagittal T1-weighted SE location sequence (TR 400, TE 20), an axial T1-weighted SE (TR 400, TE 20), two axial T2-weighted FSE sequences (TR 3000, TE 102, ETL 8) with and without fat suppression, and a coronal T2-weighted FSE sequence (TR 3000, TE 102, ETL 8); an axial Fast Multiplanar Spoiled Gradient Recalled (FMSPGR) dynamic sequence after Gd-DTPA injection was also performed in 18 patients. MR staging of local tumor spread was done according to the current literature criteria. All patients were submitted to radical prostatectomy, and histologic macrosections on the same plane as MR images were obtained from surgical specimens. MR and histologic staging were compared to assess MR accuracy in detecting capsular infiltration, seminal vesicles and apex involvement. The diagnostic yield of Gd-DTPA was also investigated. RESULTS: MRI correctly staged 31 of 40 cases (77.5%). MR accuracy was 80% in detecting capsular infiltration (85.7% sensitivity and 73.6% specificity), 90% in seminal vesicle involvement (91.6% sensitivity, 89.2% specificity) and 72.5% in apex involvement (79.1% sensitivity, 62.5% specificity). Dynamic studies with Gd-DTPA did not improve staging accuracy in any case. DISCUSSION AND CONCLUSIONS: In agreement with most of the current literature, MRI showed moderate overall accuracy in the local staging of prostate carcinoma. Particularly, MRI had good accuracy in detecting seminal vesicle involvement but moderate sensitivity and specificity in demonstrating capsular infiltration and apex involvement. Due to its high cost, MRI should not be routinely used in prostate cancer staging but should be reserved to the patients whose clinical and serological data suggest extraprostatic tumor spread, whose preoperative demonstration could avoid noncurative surgery.     

1.5.T和3.0T磁共振检查在直肠癌术前分期价值的比较

目的:探讨1.5T和3.0T磁共振检查在直肠癌诊断和术前分期中的作用,分析两者在直肠癌术前分期的应用价值.方法:选择经肠镜活检证实为直肠癌病人60例,随机盲法均分为两组.分别行1.5T和3.0T磁共振检查及术前直肠癌影像分期,并与病理分期对照.结果:1.5T MRIT分期总准确性为80%,N分期总准确率为67%,N0分...     

Preoperative local staging of rectal cancer with endorectal MR imaging: comparison with histopathologic findings

The purpose of this prospective study was to assess the accuracy of endorectal MR imaging in the preoperative local staging of rectal cancers. In 20 cases, we correlated endorectal MR imaging findings with postoperative histopathologic staging according to TNM classification. The accuracy of endorectal MR for determining the T stage of rectal cancer was 85%. The sensitivity and specificity for detecting lymph node metastases were 90.9% and 55.5%, respectively.     

MRI对中低位直肠癌TaTME术前分期及可切除性评估

目的探讨1.5T MRI对中低位直肠癌经肛全直肠系膜切除术(TaTME)术前分期及可切除性评估,以指导直肠癌的TaTME个体化治疗,提高患者的保肛率和长期生存率、降低局部复发率。方法选取我院62例经结肠镜证实的中低位直肠癌患者进行盆腔高分辨平扫、DWI检查,常规序列包括:失状位T₂WI、斜冠状位T₂WI、斜轴位T₂WI和DWI,所有T₂WI序列都采用小视野、薄层扫描。DWI的b值取1000 s/mm²。然后由两名腹部影像诊断医师共同阅片,矢状位测量病灶下缘距离肛门外括约肌下缘的距离、矢状位病灶最大长径、斜轴位病灶最大长径,综合所有序列对直肠癌病灶进行术前MRI-TN分期,评估直肠系膜筋膜(MRF)累及的情况,然后与手术病理结果进行对照。结果在手术病理证实的62例中低位直肠癌中,中段直肠癌38例,下段直肠癌24例。肿块下缘距肛缘的平均距离(5.2±2.5)cm,肿块矢状位最大长径(4.0±1.8)cm,肿块斜轴位最大横径(2.9±1.2)cm。MRI-T分期中正确诊断51例,错误诊断11例,正确率为82.2%。MRI-N分期中正确诊断41例,错误分期21例,正确率为66.1%。MRI判别MRF有无累及的准确率、敏感性、特异性、阳性预测值及阴性预测值分别为88.9%、88.6%、76.2%及95.1%。结论高分辨1.5T MRI可以对中低位直肠癌做出准确的术前局部分期,对手术切缘有无累及进行准确的预测,准确预判手术的可切除性,为直肠癌TaTME的临床个体化治疗提供影像依据及解剖学标记。     

高分辨率MRI扩散加权成像对直肠癌术前T、N分期及环周切缘判断的价值

目的探讨高分辨率MRI扩散加权成像(DWI)对直肠癌患者术前T、N分期与环周切缘的判断价值。方法对收治的直肠癌127例患者行MRI与DWI检查,根据术后病理结果,分析MRI与DWI对直肠癌术前T分期与N分期的诊断价值以及对环周切缘的判断价值。结果MRI诊断T1期敏感度92.00%、特异度99.02%;T2期敏感度92.31%、特异度97.03%、T3期92.68%、特异度98.84%;T4期敏感度91.43%、特异度100.0%。MRI对N0期诊断敏感度93.02%、特异度94.05%、N1期敏感度89.13%、特异度97.53%、N2期敏感度93.33%、特异度100.0%。经单因素方差分析显示,不同分期患者b=800 mm^2/s基线下ADC值,差异具有统计学意义(P<0.05);其中T1、T2、T3期ADC值显著高于T4期,T1期显著高于T2、T3期,差异具有统计学意义(P<0.05)。b=800 mm^2/s基线下ADC值对T1期直肠癌患者的AUC为0.834、对T2期0.651、T3期0.546、T4期0.837。经单因素方差分析显示不同N分期患者ADC值,差异具有统计学意义(P<0.05)。结论MRI诊断直肠癌患者术前T、N分期具有较高价值,而DWI检查中b值基线下ADC在一定程度上可反映肿瘤细胞分化程度。     

Staging of rectal cancer by double-contrast MR imaging using the rectally administered superparamagnetic iron oxide contrast agent ferristene and IV gadodiamide injection: results of a multicenter phase II trial

The aim of this study was to assess the accuracy of double-contrast magnetic resonance imaging (MRI) with rectal application of the superparamagnetic iron oxide contrast agent (SPIO) ferristene and IV gadodiamide for preoperative staging of rectal cancer. In a randomized phase II dose-ranging trial, 113 patients were studied preoperatively with one of four different formulations of ferristene (Abdoscan) as an enema before MRI. T1-weighted spin-echo (T1w SE) and T2w turbo spin-echo (TSE) single-contrast images were obtained as well as T1w SE and gradient-echo (GRE) double-contrast images after IV gadodiamide injection (Omniscan). Images were assessed qualitatively, and TNM tumor stage was compared with histopathology. High-viscosity ferristene formulations were superior to low-viscosity formulations in tumor staging (accuracy 90% vs 74%, P < 0.01). There was no significant difference between high and low iron content ferristene. MRI had a sensitivity of 97%, specificity of 50%, and accuracy of 82% for staging of rectal carcinoma higher than T2 stage. At receiver operator characteristic (ROC) analysis, MR differentiation between T1/T2 and T3/T4 tumor stages yielded a ROC index of 0.848. Double-contrast MRI is an accurate method for preoperative staging of rectal cancer.