Use of preoperative MR imaging in the management of endometrial carcinoma: cost analysis

PURPOSE: To compare the cost of magnetic resonance (MR) imaging and its ability to direct the use of lymph node dissection with the cost and ability of conventional surgery for the staging of endometrial carcinoma. MATERIALS AND METHODS: Preoperative MR images of 25 patients who underwent hysterectomy for endometrial carcinoma were retrospectively evaluated. MR imaging results were compared with those of intraoperative gross dissection of the uterus and final histopathologic examination. Medicare reimbursements for two scenarios were compared in each patient. In the MR imaging scenario, the necessity for lymph node dissection was based on MR imaging results and histologic findings at biopsy. In the actual scenario, lymph node dissection was performed at the surgeon's discretion on the basis of findings at gross dissection of the uterus and histologic examination at biopsy. RESULTS: The cost of the MR imaging scenario, as defined by Medicare reimbursements, was 1% ($1, 265/$148,500) less than that of the actual scenario. In the MR imaging scenario, all patients who required lymph node dissection received it, and 86% of the lymph node dissections performed were necessary. In the actual scenario, one necessary lymph node dissection was not performed, and only 31% of the lymph node dissections performed were necessary. CONCLUSION: Staging with MR imaging has costs and accuracy similar to those of the current method of staging with intraoperative gross dissection of the uterus. In addition, MR imaging decreases the number of unnecessary lymph node dissections.     

Differentiation of metastatic versus non-metastatic mediastinal lymph nodes in patients with non-small cell lung cancer using respiratory-triggered short inversion time inversion recovery (STIR) turbo spin-echo MR imaging

OBJECTIVES: To differentiate between metastatic and non-metastatic lymph nodes in patients with non-small cell lung cancer using respiratory-triggered short inversion time inversion recovery (STIR) turbo spin-echo (SE) MR imaging. METHODS AND PATIENTS: One hundred and forty mediastinal lymph nodes were detected in 25 patients with non-small cell lung cancer who underwent respiratory-triggered STIR turbo SE imaging. Ratios of signal intensity of lymph nodes to 0.9% saline phantoms (lymph node-saline ratio) were compared by Student's t-test using the pathological diagnosis as the gold standard. The threshold value of the lymph node-saline ratio was determined for a positive test, and tested for its capability to provide a differential diagnosis. RESULTS: One hundred and forty lymph nodes were diagnosed and classified into two groups: metastatic lymph node (n=21) and non-metastatic lymph node (n=119). The mean lymph node-saline ratio in the non-metastatic lymph node group (0.42+/-0.01; mean+/-standard error) was significantly lower than that of the metastatic lymph node group (0.77+/-0.02, P<0.0001). When 0.6 was adapted as the threshold for a positive test, sensitivity, specificity, and accuracy for differentiating metastatic lymph node from non-metastatic lymph node per lymph nodes were 100, 96, and 96%, and sensitivity, specificity, and accuracy for differentiating metastatic lymph node from non-metastatic lymph node per patients were 100, 75, and 88%, respectively. CONCLUSIONS: Both metastatic and non-metastatic lymph nodes in patients with non-small cell lung cancer were well differentiated using respiratory-triggered STIR turbo SE imaging.     

定量MRI诊断直肠癌淋巴结转移的研究进展

评估直肠癌淋巴结转移对治疗和预后至关重要。常规MRI诊断直肠癌淋巴结转移主要依据淋巴结的短径和形态学特征,诊断效能较低。定量MRI包括动态增强MRI（DCE-MRI）、动态磁敏感增强MRI（DSC-MRI）、单指数模型扩散加权成像（DWI）、扩散峰度成像（DKI）、体素内不相干运动扩散加权成像（IVIM-DWI）等,可以对直肠癌淋巴结及原发灶进行定量分析,从而有助于诊断淋巴结转移。就常规MRI及定量MRI诊断直肠癌淋巴结转移的研究进展予以综述。     

Imaging axillary lymph nodes in patients with newly diagnosed breast cancer

The presence of axillary lymph node metastasis in patients newly diagnosed with breast cancer carries significant prognostic and management implications. As a result, there is increasing interest to stage accurately the axilla with preoperative imaging to facilitate treatment planning. Currently, the most widespread imaging techniques for the evaluation of the axilla include ultrasound and magnetic resonance imaging. In many settings, the ability to detect axillary lymph nodes containing metastases with imaging and image-guided biopsy can allow surgeons to bypass sentinel lymph node dissection and proceed with full axillary lymph node dissection. However, no imaging modality currently has sufficient negative-predictive value to obviate surgical staging of the axilla if no abnormal lymph nodes are detected. Promising advanced imaging technologies, such as diffusion-weighted imaging and magnetic resonance lymphangiography, hold the potential to improve the accuracy of axillary staging and thereby transform management of the axilla in patients newly diagnosed with breast cancer.     

99Tcm-MIBI显像对乳腺癌腋窝转移淋巴结的诊断

目的 评价＾９９Ｔｃ＾ｍ－甲氧基异丁基异腈（ＭＩＢＩ）显像要诊断乳腺癌腋窝转移淋巴结中的价值,方法 １８例病理检查证实的乳腺癌病人,术前均行＾９９Ｔｃｍ－ＭＩＢＩ显像,１４例乳腺未触及肿块者作为对照组,静脉注射＾９９Ｔｃ＾ｍ－ＭＩＢＩ１１０ＭＢｑ后５,３０和６０ｍｉｎ进行早期及延迟显像,分别于左侧位,右侧位和前后位进行观察,患者均在显像扣１周内进行手术治疗,腋窝淋巴结清扫后行病理检查。结果 １８例     

MR imaging of infradiaphragmatic lymphadenopathy in children and adolescents with Hodgkin disease: Comparison with lymphography and CT

The ability of short-inversion-time inversion recovery (STIR) magnetic resonance imaging to depict infradiaphragmatic lymphadenopathy was evaluated in 25 consecutive patients with newly diagnosed Hodgkin disease. All patients underwent computed tomography (CT) and multiplanar STIR imaging prior to lymphography (LAG). The STIR and CT images were evaluated for paraaortic and parailiac node enlargement. Findings were compared with LAG findings, which showed the architectural pattern of the opacified lymph nodes. In the upper paraaortic region, STIR imaging showed more abnormal nodes than did CT or LAG. In the lower paraaortic and parailiac regions, lymph node enlargement was shown equally well with STIR and LAG, whereas CT showed fewer enlarged lymph nodes. LAG showed paraaortic or parailiac focal tumor infiltration in three patients with normal-size nodes, and hyperplasia in two patients with enlarged nodes. STIR imaging showed more abnormal infradiaphragmatic nodes than did CT because of improved lymph node conspicuity. STIR imaging may be a useful addition to CT for staging pediatric Hodgkin disease.     

胰腺癌胰周淋巴结转移分布特征的螺旋CT表现

目的:胰腺癌胰周淋巴结转移的分布特征及螺旋CT影像表现。方法:搜集经手术病理诊断为原发性胰腺癌45例,所有病例均经手术病理或影像标准诊断有胰周淋巴结转移。根据本组45例病例CT所反映的肿大淋巴结的分布情况,将胰周淋巴结分为8组。设定淋巴结的短径≥1.0cm为淋巴结转移阳性的影像表现。统计阳性淋巴结的出现率,重点观察淋巴结转移的部位、大小、数目、形态、密度、强化情况。结果:本组45例胰腺癌中,共计89个部位观察到淋巴结转移胰周转移淋巴结以腹腔动脉干组46.7%(21例),肠系膜根部组46.7%(21例),腹主动脉周围组35.6%(16例)为最多,胃周11.1%(5例)及脾动脉-脾门组13.3%(6例)最少。结论:胰腺癌转移所致肿大淋巴结主要分布在腹腔干、肠系膜根部以及腹主动脉周围。螺旋CT扫描检查可以较准确显示胰腺癌胰周淋巴结的转移情况。     

Detection of pelvic lymph node metastases in gynecologic malignancy: a comparison of CT, MR imaging, and positron emission tomography.

OBJECTIVE: Accurate assessment of lymph node status before treatment is critical in the treatment of gynecologic cancers because the 5-year survival and treatment of women is influenced by lymph node involvement. The aims of this study were to investigate the ability of X-ray CT, MR imaging, and (18)F-FDG positron emission tomography (PET) to detect pelvic lymph node metastases by comparing imaging with histopathologic findings after lymph node dissection. MATERIALS AND METHODS: Eighteen patients with gynecologic cancers were studied by all three imaging methods before surgery. The images were initially reviewed with routine diagnostic conditions and then, subsequently, by two observers who were unaware of the clinical and histopathologic findings of the patients. The nodal sites were split into upper (aortic to common iliac bifurcations) and lower (common iliac bifurcations to inguinal ligament) iliac chains. All observers' results were statistically analyzed with specificity, sensitivity, positive and negative predictive values, Fisher's exact test (individual observers) or chi-square test (combined observers), and Cohen's kappa test. RESULTS: Eight of 18 patients had lymph node metastases at histology. Findings of all three modalities agreed in full in only one patient. CT correctly revealed 10 node-negative patients, whereas MR imaging was correct in eight of these patients. (18)F-FDG PET correctly depicted one patient with lymph nodes negative for tumor. CT was the most specific imaging modality (97.0%), with MR imaging and PET rendering values of 90.7% and 77.3%, respectively, but sensitivity of all modalities was low (CT, 48.1%; MR imaging, 53.7%; PET, 24.5%). Observer agreement for each modality was good; kappa values among all observers were 0.88 for CT, 0.85 for MR imaging, and 0.72 for PET. CONCLUSION: CT is the most specific modality for detecting lymph nodes positive for tumor in gynecologic cancers, whereas MR imaging is the most sensitive. The poor results of PET in the pelvis are attributed to urinary (18)F-FDG in the ureters or bladder, which may mask or imitate lymph node metastases.     

False-negative cases of axillary ultrasonography: how much size?

PURPOSE/AIM: 1. To review the sonographic criteria of axillary lymph node status in breast cancer patients. 2. To understand imaging pathologic correlations that the false-negative cases of axillary ultrasonography. CONTENT ORGANIZATION: The sonographic criteria, the accuracy of sonographic axillary ultrasonography, imaging pathologic correlations in false-negative cases, measurement of largest malignant focus size in lymph node, classification of ratio of malignant focus size, ratio of micro metastasis. SUMMARY: 1. Recently, lymph node evaluation that using serial section and immunohistochemical stains makes it difficult to detect imaging modalities. 2. Ultrasonography is limited how to detect the example of sentinel lymph node biopsy non-indications.     

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.     

影像技术在乳腺癌内乳淋巴结转移检测方面的研究进展

在乳腺癌疾病研究中,内乳淋巴结转移是继研究腋窝淋巴结转移之外又一研究重点,运用影像学技术对其转移征象的检测仍处于初步探索中。目前淋巴结闪烁显像,X线技术,超声及其造影,CT及其核磁技术等各种影像技术已在该方面有所进展。     

新型特异性靶向前哨淋巴结示踪剂的研究进展

前哨淋巴结活检术（SLNB）广泛应用于乳腺癌、黑色素瘤等恶性肿瘤,其使用的示踪剂主要有放射性核素示踪剂和活性蓝染料,包括近年应用较多的荧光示踪剂,均为非特异性示踪剂,且存在次级淋巴结显影的问题。以B细胞表面的CD20抗原和巨噬细胞表面的甘露糖受体CD206为靶点的新型特异性靶向前哨淋巴结（SLN）示踪剂,通过放射性核素、荧光或两者共同对其进行标记,与常规示踪剂相比,其具有注射部位快速清除、SLN可快速、高摄取以及较少的远端淋巴结显影等特点,满足理想示踪剂的特性。此外,受体靶向荧光放射性药物可以实现术前放射性核素显像与术中荧光成像,研究应用于前列腺癌、结肠癌等肿瘤的SLN活检。笔者主要对新型特异性靶向SLN示踪剂的研究进展进行综述。     

68Ga-PSMA PET-CT与mpMRI显像对前列腺癌淋巴结转移的诊断价值比较

 目的 系统评价⁶⁸Ga-PSMA PET/CT与mpMRI显像对前列腺癌淋巴结转移的诊断价值。方法 通过检索国内外中英文数据库,纳入⁶⁸Ga-PSMA PET/CT与mpMRI显像诊断前列腺癌淋巴结转移的诊断性临床试验,并分别基于患者或病灶提取文献中的原始数据。通过软件将数据合并进行分析,分别合并⁶⁸Ga-PSMA PET/CT与mpMRI显像诊断前列腺癌淋巴结转移的敏感性(sensitivity,SEN)、特异性(specific,SPE)、阳性似然比(positive likelihood ratio,PLR)、阴性似然比(negative likelihood ratio,NLR)、诊断比值比(diagnostic odds ratio,DOR)以及SROC曲线下面积(area under curve,AUC)等。结果 共纳入13篇符合条件的文献,系统评价结果显示,基于患者的分析结果中,⁶⁸Ga-PSMA PET/CT与mpMRI对前列腺癌淋巴结转移的SEN、SPE、PLR 、NLR、DOR、AUC分别为0.44、 0.93、5.25、 0.61、 9.6、0.90及0.44、0.95、5.46、0.62、12.06、0.90。基于淋巴结的分析结果中,⁶⁸Ga-PSMA PET/CT与mpMRI对前列腺癌淋巴结转移的SEN、SPE、PLR 、NLR、DOR、AUC分别为0.58、0.99、61.22、0.24、 308.06、0.99及0.61、0.99、27.17、0.36、90.48、0.99。结论 ⁶⁸Ga-PSMA PET/CT与mpMRI显像诊断前列腺癌淋巴结转移的特异性均很高、敏感性欠佳, mpMRI对于PCa淋巴转移的诊断可能更具有临床价值。     

MR Lymphography with a Lymphotropic T1-Type MR Contrast Agent: Gd-DTPA-PGM

A model system of a paramagnetic lymphotropic MR contrast agent (Gd-DTPA labeled polyglucose associated macrocomplex, PGM) for T¹-weighted MR imaging of lymph nodes in rats and rabbits was evaluated. Pharmacokinetic (tissue accumulation) and MR imaging data (optimal dose and timing parameters) were obtained in normal rats (n = 88) after subcutaneous (SC) injection of paramagnetic, radiolabeled [111In]Gd-DTPA-PGM. A rabbit model of lymph node metastases (n = 8) was ultimately used to demonstrate the potential of MR imaging with Gd-DTPA-PGM for nodal tumor detection. Maximum concentrations of Gd-DTPA-PGM were found in popliteal and paraaortic lymph nodes within 24 h after SC administration, and highest lymph node SNR values were obtained by MR imaging at this time point. The optimum imaging dose was 6–12 μmol Gd/kg. Tumor-lymph node contrast increased from 0.0 ± 1.2 precontrast to 19.2 ± 6.5 (spoiled gradient echo sequence, TR 50/TE 7/flip angle 60°) postcontrast and conspicuity of nodal metastases was improved. Gd-DTPA-PGM accumulates in lymph nodes after SC administration and significantly enhances lymph node signal intensity of normal animals but not metastatic lymph nodes.     

Whole-body 18F dopa PET for detection of gastrointestinal carcinoid tumors

PURPOSE: To evaluate fluorine 18 (18F) dopa positron emission tomography (PET) in comparison with established imaging procedures in gastrointestinal carcinoid tumors. MATERIALS AND METHODS: After evaluation of the normal distribution of 18F dopa, 17 patients with histologically confirmed tumors were examined with 18F dopa PET. Results of 2-[fluorine 18]fluoro-2-deoxy-D-glucose (FDG) PET, somatostatin-receptor scintigraphy, and morphologic imaging (computed tomography and/or magnetic resonance imaging) were available for all patients. Results of the procedures were evaluated by two radiologists and two nuclear medicine specialists, whose consensus based on all available histologic, imaging, and follow-up findings was used as the reference standard. RESULTS: Ninety-two tumors were diagnosed: eight primary tumors, 47 lymph node metastases, and 37 organ metastases. 18F dopa PET led to 60 true-positive findings (seven primary tumors, 41 lymph node metastases, 12 organ metastases); FDG PET, 27 (two primary tumors, 14 lymph node metastases, 11 organ metastases); somatostatin-receptor scintigraphy, 52 (four primary tumors, 27 lymph node metastases, 21 organ metastases); and morphologic imaging, 67 (two primary tumors, 29 lymph node metastases, 36 organ metastases). This resulted in the following overall sensitivities: 18F dopa PET, 65% (60 of 92); FDG PET, 29% (27 of 92); somatostatin-receptor scintigraphy, 57% (52 of 92); morphologic procedures, 73% (67 of 92). Although the morphologic procedures were most sensitive for organ metastases, 18F dopa PET enabled best localization of primary tumors and lymph node staging. CONCLUSION: 18F dopa PET is a promising procedure and useful supplement to morphologic methods in diagnostic imaging of gastrointestinal carcinoid tumors.     

Comparison as a lymphoscintigraphic agent between 99Tcm dextran and 99Tcm antimony sulphide colloid

To determine its suitability as a lymph node imaging agent, 99Tcm dextran (99TcmDx) was compared with 99Tcm antimony sulphide colloid (99TcmSb2S3) in rabbits and dogs. In two groups of five rabbits each, absorption from the interstitial injection site, popliteal lymph node sequestration and total body uptake and distribution of both agents were determined. In three dogs, both agents were studied simultaneously, 99TcmDx and 99TcmSb2S3 being injected into the left and right hind feet respectively; therefore, only popliteal lymph node sequestration and image qualities were evaluated. Uptake curves in the rabbits indicated that total body uptake of 99TcmDx is faster and greater than that of 99TcmSb2S3. In spite of rapid lymph node uptake rates, total popliteal lymph node sequestration of 99TcmDx is significantly lower than that observed for 99TcmSb2S3. While lymph node uptake of 99TcmDx in dogs is higher than in rabbits, disparity between the two agents persists and is demonstrable in the image in both species. Reduced lymph node sequestration of 99TcmDx may result from its non-colloidal nature as well as its instability, both of which render this agent unsuitable for imaging pathological features of lymph nodes although its rapid absorption and distribution may be ideal characteristics for the study of lymphatic kinetics.     

Cervical lymph nodes

The lymph node staging is a very important prognostic parameter for patients with presenting with head neck cancer and is influencing the selection of the different therapeutic strategies including surgery, chemotherapy, radiotherapy or a combination of them. The accuracy of imaging techniques, such as US, MR imaging, and CT, depends on the appropriateness of radiological criteria used for diagnosing lymph node metastases. Size of nodes and evidence of necrosis are still the most important radiological criteria. However, the size shows great variability. A spherical lymph node larger than 10mm is an indicator for a malignant node, whereas an oval shape and/or a fatty hilus are more benign signs. But there are many limitations and different cut offs published in the literature, indicating that the size of a lymph node is not a reliable criteria for the assessment of lymph nodes in the head and neck region. Today new high-resolution MRI sequences and the development of specific contrast agents are offering new possibilities in the diagnostic work-up of head and neck lymph nodes. Ultrasmall superparamagnetic iron oxide particles (USPIO's) are resulting after intravenous application in a reduction of the T2 relaxation time. This is causing a signal decrease on T2-weighted MR images in benign lymph nodes after administration of USPIO's, whereas malignant lymph nodes do not show a significant signal decrease. Some clinical studies presented already very promising results. Based on the fact, that the size evaluation of lymph nodes in the head and neck has not changed during the last decade, this paper will mainly focus on MRI with new contrast agents and new techniques as diffusion weighted imaging (DWI).     

Study of the lymph flow of the cardia by endoscopic RI-lymphography with SPECT

Endoscopic RI-lymphography was performed in 29 patients, with single photon emission computed tomography (SPECT) also performed in 19 of them. The lymph flow from the cardia was directly evaluated in lymphograms and compared with the RI uptake of each lymph node and the incidence of lymph node metastasis of previously resected carcinoma of the cardia in patients according to the location of the lymph node. Endoscopic RI-lymphography performed in combination with SPECT was considered to be highly useful for imaging lymph flow of the cardiac region. SPECT and RI-lymphography indicated rich lymph flow from the cardia to the periaortic region, and this finding was consistent with the incidence of lymph node metastasis according to the location of the lymph node in patients who had previously undergone resection of cancer of the cardia. Careful examination for metastasis to lymph nodes around the abdominal aorta was considered to be necessary, especially in patients with carcinoma of the cardia.     

颈部肿大淋巴结的影像分析

目的探讨颈部肿大淋巴结影像表现特点,提高诊断的准确性。方法66例经临床和病理证实的颈部肿大淋巴结患者,均进行CT和/或MR I检查,对比分析他们的影像学表现。结果多发的转移性淋巴结与多发的结核性淋巴结在位置分布上有显著性差异(P=0.006)。转移性淋巴结环形强化20例,其薄壁环形强化19例,占95%,而淋巴结结核环形强化5例均为厚壁环形强化,两者具有显著差异性(P=0.000)。转移性淋巴结中心坏死占78%,而淋巴瘤仅占36%,两者有显著性差异(P=0.018)。结论根据颈部肿大淋巴结位置分布和影像表现特点,大部分可做出正确诊断。     

Prostate and lymph node proton magnetic resonance (MR) spectroscopic imaging with external array coils at 3 T to detect recurrent prostate cancer after radiation therapy

In a patient suspected of having recurrent prostate cancer after radiation therapy, we demonstrate the feasibility of noninvasive proton magnetic resonance spectroscopic (1H-MRS) imaging of the prostate and a lymph node at 3 T using a matrix of external surface coils. Written informed consent was obtained from the patient. With 1H-MRS imaging, high choline with low citrate signal was observed in the prostate, and in the lymph node a signal of choline-containing compounds was identified. The tissue level of the compounds in the enlarged lymph node was estimated to be 8.1 mmol/kg water. Subsequent histopathological analysis of systematic transrectal ultrasound-guided prostate biopsy and computed tomography-guided biopsy of the lymph node confirmed the presence of prostate cancer in both.