CT能谱曲线对非小细胞肺癌胸内淋巴结转移诊断价值

目的评价能谱CT成像技术中能谱曲线在判断术前非小细胞肺癌胸内淋巴结转移的诊断价值。方法回顾性分析2013年1-12月在解放军第一一七医院诊治的53例非小细胞肺癌患者的术前胸部CT中胸内淋巴结的能谱曲线,计算曲线斜率,与原发病灶作比较。以手术病理为确诊标准,判断能谱曲线的诊断价值。结果应用能谱曲线分析126组淋巴结。其中,转移性淋巴结31组(斜率为1.19±0.14),非转移性淋巴结95组(斜率为1.87±0.23);两组结果相符合共115组,不符合有11组。其中,病理结果为转移性淋巴结,而能谱分析为非转移有4组;病理结果为非转移性淋巴结,而能谱曲线为转移性淋巴结有7组。灵敏度为87.1%;特异度为92.6%;误诊率为7.4%;漏诊率为12.9%;阳性预测值为79.4%;阴性预测值为95.7%;准确度为91.3%;正确指数为79.7%。结论能谱CT成像技术中的能谱曲线,在术前评估淋巴结转移时具有较高的参考价值,能够为手术方案的制定提供依据。     

结直肠癌双层探测器光谱CT成像：转移性与非转移性淋巴结的对照研究

【摘要】目的：探讨双层探测器光谱CT（DLCT）成像技术对结直肠癌转移性与非转移性淋巴结的鉴别诊断价值。方法：回顾性分析2019年12月－2020年11月在本院行腹部DLCT检查且经病理证实为结直肠癌的41例患者的病例资料。41例患者共纳入113枚局部淋巴结,其中经病理检查证实为转移性淋巴结40枚,非转移性淋巴结73枚。由两位放射科医师共同分析每枚淋巴结的DLCT图像,分别在动脉期和静脉期图像上测量淋巴结的碘浓度、有效原子序数及能谱曲线（40~100keV）的斜率,比较转移性与非转移性淋巴结光谱参数值的差异,将有统计学差异的参数纳入Logistic回归方程,筛选出有鉴别诊断价值的参数,并采用ROC曲线分析其诊断效能。结果：转移性淋巴结的动、静脉双期碘浓度、有效原子序数及能谱曲线斜率均低于非转移性淋巴结（P＜0.05）。动脉期的碘浓度和能谱曲线斜率为转移性淋巴结的独立预测因子,预测淋巴结转移的AUC分别为0.795和0.809,敏感度分别为0.704和0.778,特异度均为0.722。结论：DLCT定量参数对结直肠癌患者转移性与非转移性淋巴结的鉴别诊断具有一定价值,其中以动脉期能谱曲线斜率的诊断效能最高。     

MRI-DWI技术对直肠癌及术前分期的诊断价值分析

目的探讨MRI增强扫描结合弥散加权成像对直肠癌诊断及术前评估的价值。方法选取2016年1月~2016年11月期间我院接收的58例直肠癌患者,均行MRI增强扫描结合弥散加权成像检查,观察诊断价值。结果 b=1200s/m2时,高分化、中分化、低分化组间比较有明显差异(P0.05);MRI结合DWI对于T期分期总诊断符合率为89.7%,与病理学T分期间一致性检验好(kappa=0.76);58例患者伴有39例淋巴结转移,MRI术前共检出可疑阳性淋巴结285枚,术后病理检查为223枚。转移性淋巴结ADC值显著高于良性淋巴结(P0.05)。结论 MRI-DWI对直肠癌进行诊断及分期有较高的价值,且有利于术前评估淋巴结的良恶性,以便于临床医师治疗方案的制定,具有推广价值。     

CT征象及能谱定量参数Nomogram模型鉴别直肠癌肠周脂肪癌性浸润与炎性浸润

【摘要】目的：联合CT征象及能谱定量参数建立基于Logistic回归的Nomogram预测模型鉴别有浸润征象的直肠癌肠周脂肪是癌性浸润还是炎性浸润。方法：搜集能谱增强CT检查肠周脂肪具有浸润征象的直肠癌患者62例,根据病理结果分为癌性浸润组32例,炎性浸润组30例。比较两组CT征象及能谱参数的差异,筛选鉴别诊断意义较大的特征建立Logistic回归模型,绘制Nomogram、ROC曲线图及校准曲线图。结果：鉴别意义较大的特征为肠周淋巴结增大（短径≥5mm）、动脉期水浓度差（Water差）和有效原子序数（Effective-Z）、静脉期Water差和碘浓度差（Iodine差）、延迟期Water差和标准化碘浓度差（NIC差）。上述七个特征纳入多因素Logistic回归模型绘制Nomogram,模型符合率为95.2%,ROC曲线下面积（AUC）为0.986,预测能力校准曲线示预测浸润和实际浸润一致性较高。结论：基于CT征象及能谱CT定量参数建立Nomogram预测模型在鉴别有浸润征象的直肠癌肠周脂肪是否伴随癌性浸润有重要价值。     

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。     

The Application Value of Background Suppression Diffusion Weighted Imaging (DWIBS) in Preoperative Staging of Rectal Cancer

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扩散加权成像对结直肠癌区域淋巴结转移的诊断价值

目的探讨MR扩散加权成像(DWI)诊断结直肠癌区域淋巴结转移的价值。方法 75例结直肠癌病人在接受常规MR及DWI检查后均接受肿瘤切除术,对照术后病理结果,确定区域转移性和非转移性淋巴结,测量淋巴结及原发肿瘤的ADC值,比较受试者操作特征(ROC)曲线下面积(AUC),评估淋巴结的ADC值及rADC值(淋巴结/原发肿瘤)对鉴别诊断转移性与非转移性淋巴结的价值。结果转移性淋巴结60个,非转移性淋巴结126个。转移性淋巴结与非转移性淋巴结的ADC值分别为(0.79±0.12)×10-3mm2/s和(0.98±0.23)×10-3mm2/s(P<0.01);转移性淋巴结的rADC值低于非转移性淋巴结(0.91±0.14︰1.21±0.28),差异有统计学意义(P<0.01)。两组淋巴结ADC值的ROC曲线的AUC为0.776,阈值1.11×10-3mm2/s,敏感度为61.9%,特异度为88.0%;rADC值的AUC为0.883,阈值为1.03,敏感度为78.6%,特异度为90%。结论 DWI对诊断结直肠癌区域淋巴结转移有一定价值,用rADC值诊断淋巴结转移的准确性高于ADC值。     

3.0T MR高分辨率成像对直肠癌局部浸润的术前影像学评价

目的 探讨3.0T MR高分辨率成像在直肠癌术前局部浸润的评估价值.方法 回顾性分析经手术病理证实的直肠癌患者168例,术前均行MRI常规盆腔、直肠高分辨成像.评价3.0T MR高分辨成像术前T分期的准确性;探讨T3期直肠癌局部浸润特征性影像学表现.结果 直肠癌累及肠周径程度与病理T分期呈中等正相关(rs=0.530, P=0.003).MRI直肠癌T分期与病理T分期比较,总体诊断准确度为84.52%,各分期MRI征象与病理T分期有较强的相关性(rs=0.837,P=0.001).MRI诊断T3期直肠癌中,各单一征象以肿瘤结节样外凸特异性最高(91.1%),肌层信号中断灵敏度最好(89.7%).而各叠加征象中则以肠壁索条影+肌层信号中断特异性最高(89.3%),灵敏度最好(78.0%).结论 3.0T MR高分辨成像能较好显示直肠癌局部浸润表现,对术前T分期有一定的临床应用价值.     

直肠癌的CT表现及其对术前分期的意义

目的分析直肠癌的CT特征,并评价其诊断意义。方法回顾性分析经手术、病理证实的18例直肠癌病例的临床与CT资料,并依据CT表现对18例直肠癌病变进行了术前CT分期。结果直肠癌的CT表现主要为肠壁增厚,肠腔内肿块,肠腔狭窄,肠周浸润,淋巴结转移。术前CT正确分期15例（83.3%）。结论直肠癌术前CT检查对病变的严重程度的判断,设计合理的治疗和手术计划以及预后的估计具有很高的临床应用价值。     

双能量CT在肺肿瘤诊断及治疗中的研究进展

双能量CT(DECT)成像相较于传统CT成像对肺肿瘤的诊治具有独特优势。DECT可以提供不同物质定量信息,并通过多参数和定量参数分析,可提高肺结节的良恶性鉴别及肺肿瘤分型诊断的准确率,评估肺肿瘤的分级、分期,对肺肿瘤放化疗后效果及治疗后复发率等提供有效信息。能谱CT参数与预测因子的相关性,可为临床的靶向治疗提供方向。就DECT对肺肿瘤的诊断及治疗的研究进展予以综述。     

Dual-energy CT can detect malignant lymph nodes in rectal cancer

BackgroundThere is a need for an accurate and operator independent method to assess the lymph node status to provide the most optimal personalized treatment for rectal cancer patients.This study evaluates whether Dual Energy Computed Tomography (DECT) could contribute to the preoperative lymph node assessment, and compared it to Magnetic Resonance Imaging (MRI).The objective of this prospective observational feasibility study was to determine the clinical value of the DECT for the detection of metastases in the pelvic lymph nodes of rectal cancer patients and compare the findings to MRI and histopathology.Materials and methodsThe patients were referred to total mesorectal excision (TME) without any neoadjuvant oncological treatment. After surgery the rectum specimen was scanned, and lymph nodes were matched to the pathology report.Fifty-four histology proven rectal cancer patients received a pelvic DECT scan and a standard MRI.The Dual Energy CT quantitative parameters were analyzed: Water and Iodine concentration, Dual-Energy Ratio, Dual Energy Index, and Effective Z value, for the benign and malignant lymph node differentiation.ResultsDECT scanning showed statistical difference between malignant and benign lymph nodes in the measurements of iodine concentration, Dual-Energy Ratio, Dual Energy Index, and Effective Z value.Dual energy CT classified 42% of the cases correctly according to N-stage compared to 40% for MRI.ConclusionThis study showed statistical difference in several quantitative parameters between benign and malignant lymph nodes. There were no difference in the accuracy of lymph node staging between DECT and MRI.     

“Rectal cancer survival: A retrospective analysis of MRI features and their association with prognosis”

PurposeTo assess rectal cancer aggressiveness using magnetic resonance (MR) imaging features and to investigate their relationship with patient prognosis.Materials and methodsClinical information and Pelvic MR scans of 106 consecutive patients with primary rectal cancer (RC) were analyzed. Clinical symptoms, age, sex, tumor location, and patient´s survival were recorded. The variables investigated by MR were: depth or mural/extramural tumor involvement, distance to mesorectal margin, lymph node involvement, vascular, peritoneal or sphincter complex infiltration. The association between imaging features and disease-free survival (DFS) was also assessed using a Kaplan-Meier model. Differences between survival curves were tested for significance using the Mantel-Cox LogRank test.ResultsThe final study population was 106 patients (65 males, 41 females). The median age was 69.5 years (range, 39-92 years). No significant differences were found between death risk and sex, age or tumor location (p>0,05). However, the relative risk (RR) of tumor mortality increased significantly with the presence of the variables: vascular infiltration (×5), T4 tumors (× 4.57), N2 lymph node involvement (more than 3 affected nodes × 4.11) and mesorectal fascia involvement (× 3,77).ConclusionTumor extension, number of pathological lymph nodes, mesorectal fascia involvement and vascular infiltration values obtained on initial MR imaging staging showed a significant difference for disease-free survival in RC at six years of control.     

PET/CT在指导直肠癌术后放疗中的意义

 目的回顾性探讨PET/CT在检测直肠癌术后患者的分期,分析PET/CT对直肠癌术后骶前软组织肿块的诊断准确率,以及对放射治疗的指导作用.方法选择手术后直肠癌29例,在行放射治疗前行PET/CT检查,其结果分别与同期的CT结果相比较.结果29例中发现7例11处高代谢灶,骶骨前间隙3例,髂骨+腰椎1例,盆腔淋巴结+肝脏2例,腹膜后淋巴结+锁骨上淋巴结1例.结论PET/CT能够更准确地反映手术后直肠癌患者的病变范围,能够指导治疗方案的选择.     

直肠周围间隙淋巴结转移的术前MSCT评估

目的:分析直肠周围间隙淋巴结转移的多层CT(MSCT)表现,探讨CT诊断直肠癌淋巴结转移(N分期)的价值.方法:术前行盆腔MSCT检查的154例直肠癌病例,均行全直肠系膜切除术,对直肠周围间隙淋巴结进行病理检查,采用双盲法,记录每枚淋巴结的CT表现,包括淋巴结短轴直径、边缘、密度、分布方式.结果:以手术病理为标准.直肠周围间隙淋巴结CT检出率为86.3%(471/546),病理共检出直肠周围间隙淋巴结546枚,CT检出481枚,其中471枚(阳性172枚,阴性299枚)淋巴结与病理相匹配.CT诊断直肠周围间隙淋巴结转移的各种判断标准(淋巴结大小、边缘、密度、分布方式)的敏感性分别为83.1%、72.2%、70.1%、73.5%,特异性分别为80.5%、85.1%、82.4%、75.1%.CT显示的淋巴结大小、边缘、密度、分布方式的差异与阳性率有显著相关性,P<0.005.结论:直肠周围间隙淋巴结有良性和恶性淋巴结,综合分析淋巴结大小、形态、密度及分布对诊断直肠周围间隙淋巴结转移有很大帮助.     

Rectal imaging: part 1, High-resolution MRI of carcinoma of the rectum at 3 T

OBJECTIVE: MRI is currently the imaging modality of choice for the detection, characterization, and staging of rectal cancer. A variety of examinations have been used for preoperative staging of rectal cancer, including digital rectal examination, endorectal (endoscopic) ultrasound, CT, and MRI. Endoscopic ultrasound is the imaging modality of choice for small and small superficial tumors. MRI is superior to CT for assessing invasion to adjacent organs and structures, especially low tumors that carry a high risk of recurrence. CONCLUSION: High-resolution MRI is an accurate and sensitive imaging method delineating tumoral margins, mesorectal involvement, nodes, and distant metastasis. In this article, we will review the utility of rectal MRI in local staging, preoperative evaluation, and surgical planning. MRI at 3 T can accurately delineate the mesorectal fascia involvement, which is one of the main decision points in planning treatment.     

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.     

Preoperative 3T MR imaging of rectal cancer: local staging accuracy using a two-dimensional and three-dimensional T2-weighted turbo spin echo sequence

PURPOSE: The purpose of our study was to evaluate the image quality and diagnostic performance of two-dimensional (D) turbo spin echo (TSE) and 3D T2-weighted TSE MR imaging in local staging of rectal cancer at 3T. MATERIALS AND METHODS: 3T phased-array MR imaging was performed in 36 consecutive patients with biopsy-proven rectal cancer. High-resolution 2D TSE images in three planes and 3D TSE images of the rectum were obtained. Two independent observers performed an image quality assessment using eight image quality characteristics. All 2D and 3D datasets were evaluated separately. MR images were prospectively evaluated by two experienced radiologists in consensus with regard to local disease. Total mesorectal excision was used as the standard of reference. The sensitivity, specificity, positive and negative predictive value, and overall accuracy were calculated. Areas under the receiver operating characteristic (ROC) curve (AUC) were determined. RESULTS: Twenty-two patients who underwent a total mesorectal excision were enrolled in this study. Significantly more motion artifacts were present with 3D TSE imaging (P=0.04). The overall sensitivity, specificity, and accuracy of muscularis propria invasion in rectal cancer using 2D T2-weighted images were 100%, 66%, and 95%, respectively. There was a statistical significant greater AUC using 2D T2-weighted images compared to 3D T2-weighted MR images (P=0.04). The ROC curves describing the results of the interpretation of 2D and 3D T2-weighted datasets regarding perirectal tissue invasion showed no statistical significant difference (P=0.41). CONCLUSIONS: In this study, high local staging accuracies with 3T 2D T2-weighted MR imaging were demonstrated. 3D T2-weighted MR imaging cannot replace 2D MR imaging for local staging of rectal cancer. However, 3D MR imaging can be used for visualization of the complex pelvic anatomy for treatment planning purposes.     

MR IVIM-DWI 及 DCE-MRI 对直肠癌系膜淋巴结良恶性的诊断价值

目的：探讨 MR 体素内不相干运动扩散加权成像(IVIM-DWI)及动态增强磁共振成像(DCE-MRI)在鉴别直肠癌直肠系膜淋巴结转移的应用价值。方法38例经病理确诊为直肠癌的患者,术前行 IVIM-DWI 及 DCE-MRI 检查。比较转移性淋巴结(n=28)与非转移性淋巴结(n=27)的短径、短径-长径比、IVIM-DWI 参数值[表观扩散系数(ADC)、单纯扩散系数(D)、伪扩散系数(D?)和灌注分数(f)]及 DCE-MRI 半定量参数值[曲线上升斜率(Slope)、最大上升斜率(Maxslope)、对比增强比(CER)、对比剂清除率(Washout)、达峰时间(TTP)、前90 s 增强曲线下面积(iAUC90)和前180 s 增强曲线下面积(iAUC180)]。结果转移性与非转移性淋巴结在平均短径(8.87 mm±2.829 mm vs 6.83 mm±1.075 mm)、D 值[(0.824±0.113)×10-3 mm2/s vs (1.033±0.244)×10-3 mm2/s)]、CER(1.588±0.664 vs 1.054±0.419)、iAUC90(22.89±9.83 vs 13.59±5.34)和 iAUC180(49.38±20.19 vs 30.31±11.67)上差异有统计学意义(P ≤0.001);在短径-长径比、ADC 值、D?值、f 值及 Slope、Maxslope、Washout、TTP 上无统计学差异(P >0.05)。鉴别转移性及非转移性淋巴结的最佳阈值(各自的曲线下面积、敏感性、特异性)分别为：短径=7.1 mm(0.744、64.2%、85.1%)、D=0.906×10-3 mm2/s (0.821、81.5%、75.0%)、CER=1.05(0.749、85.7%、62.9%)、iAUC90=13.42(0.780、85.7%、62.9%)及 iAUC180=49.65(0.770、50.0%、100%)。结论IVIM-DWI 及 DCE-MRI 在鉴别直肠癌直肠系膜转移性及非转移性淋巴结的诊断中具有一定的意义。     

Single-photon emission computed tomography/computed tomographyfor sentinel node mapping in breast cancer

Accurate lymph node staging is essential for the prognosis and treatment in patients with cancer. The sentinel lymph node is the first node to which lymphatic drainage and metastasis from the primary tumor occurs. In malignant melanoma and breast cancer, the sentinel lymph node detection and biopsy already have been implemented into clinical practice. Currently, 2 techniques are used to identify the sentinel lymph nodes: technetium-99m-labeled colloid and blue dye. After peritumoral injection, the material migrates through the lymphatics to the first lymph nodes draining the tumor. The precise anatomic localization of the sentinel lymph nodes is important for minimal invasive surgery and to avoid incomplete removal of the sentinel lymph nodes. All sentinel lymph nodes should be resected to achieve a complete nodal staging. In the inguinal or low-axillary nodal stations, planar scintigraphic images mostly are adequate for the localization of the sentinel lymph nodes. However, in the regions of the head and neck, the chest, and the pelvis, an imaging method for the more precise anatomic localization of the sentinel lymph nodes preoperatively is highly desired. Recently, integrated single-photon emission computed tomography and computed tomography (SPECT/CT) scanners have become available. Initial reports suggest that integrated SPECT/CT might have an additional value in sentinel lymph node scintigraphy in head and neck tumors and tumors draining to the pelvic lymph nodes. We evaluated the clinical use of integrated SPECT/CT in the identification of the sentinel lymph nodes in patients with operable breast cancer. In our experience, localization and identification of sentinel lymph nodes was more accurate by integrated SPECT/CT imaging in comparison with planar images and SPECT images, respectively. In this report, the experiences of sentinel lymph node imaging with SPECT/CT are summarized.     

Morphologic predictors of lymph node status in rectal cancer with use of high-spatial-resolution MR imaging with histopathologic comparison

PURPOSE: To evaluate signal intensity and border characteristics of lymph nodes at high-spatial-resolution magnetic resonance (MR) imaging in patients with rectal cancer and to compare these findings with size in prediction of nodal status. MATERIALS AND METHODS: Forty-two patients who underwent total mesorectal excision of the rectum to determine if they had rectal carcinoma were studied with preoperative thin-section MR imaging. Lymph nodes were harvested from 42 transversely sectioned surgical specimens. The slice of each lymph node was carefully matched with its location on the corresponding MR images. Nodal size, border contour, and signal intensity on MR images were characterized and related to histologic involvement with metastases. Differences in sensitivity and specificity with border or signal intensity were calculated with CIs by using method 10 of Newcombe. RESULTS: Of the 437 nodes harvested, 102 were too small (<3 mm) to be depicted on MR images, and only two of these contained metastases. In 15 (68%) of 22 patients with nodal metastases, the size of normal or reactive nodes was equal to or greater than that of positive nodes in the same specimen. Fifty-one nodes were above the area imaged, and seven of these contained metastases. The diameter of benign and malignant nodes was similar; therefore, size was a poor predictor of nodal status. If a node was defined as suspicious because of an irregular border or mixed signal intensity, a superior accuracy was obtained and resulted in a sensitivity of 51 (85%) of 60 (95% CI: 74%, 92%) and a specificity of 216 (97%) of 221 (95% CI: 95%, 99%). CONCLUSION: Prediction of nodal involvement in rectal cancer with MR imaging is improved by using the border contour and signal intensity characteristics of lymph nodes instead of size criteria.