Radiation safety of the sentinel lymph node technique in breast cancer

Many publications attest to the potential of the sentinel lymph node technique in advancing the clinical management of melanoma and, more recently, breast cancer. Whilst not yet universally regarded as the standard of care, the technique is gaining wide acceptance. Use of a radiolabelled colloidal tracer is central to optimising sensitivity, and this brings with it the need to address radiation safety issues relating to the use of radioactive materials in the operating theatre and pathology laboratory, and the generation of radioactive waste. The radiation dose to the patient should also be determined if the professional is to reassure the patient by placing this in its proper context. For the purpose of this investigation, biodistribution data were obtained from patient studies to quantify the migration of tracer beyond the injection site, thereby permitting a detailed assessment of the internal dosimetry of the tracer and the resulting radiation dose to the patient. Uptake of tracer in the sentinel nodes, reticulo-endothelial system and circulating blood was investigated. The radiation dose to surgical staff was recorded using whole-body monitors and extremity dosimeters worn at the fingers. Clinical waste in the operating theatre was monitored and the radioactive content of significantly contaminated items determined. The radiation dose to pathology staff was estimated from knowledge of the radioactive content of the specimens obtained and a study of work practices. Migration of tracer was found to be minimal, with greater than 95% retention at the injection site. The effective dose resulting to the patient was 2.1×10^–2 mSv/MBq, with a mean breast dose of 7.2×10^–1 mGy/MBq. A mean whole-body dose of 0.34 μSv was received by surgical staff per procedure, with a mean finger dose of 0.09 mSv (90 μSv). Radiation doses received by pathology staff will be predominantly below measurable levels and are likely to be negligible unless primary specimens from a large number of studies are analysed promptly upon their excision. At operation, surgical swabs can become significantly contaminated and have been found to contain up to 22% of the administered activity, dependent upon the surgical procedure performed. It is concluded that moderate activities of technetium-99m labelled tracer are administered to the patient, and the radiation risk to the patient is consequently low relative to that from many other medical exposures. The radiation doses to staff groups involved in all aspects of the technique are low, and under normal circumstances and levels of workload, routine radiation monitoring will not be required. Standard biohazard precautions prevent direct intake of radioactive contamination. Radioactive waste is created in the operating theatre, and may be generated in the pathology laboratory if specimens are not routinely stored until fully decayed. This will require special handling if the disposal of radioactive material is not permitted. Received 4 November and in revised form 14 December 1999     

Axillary lymph node metastases in breast cancer: preoperative detection with US

The importance of axillary node status in the prognosis of breast cancer led the authors to conduct a prospective study comparing the value of clinical examination with ultrasound (US) performed by a transpectoral approach. All 60 patients examined underwent axillary dissection. Sensitivity was 45.4% for clinical examination versus 72.7% for US. US provides valuable information for breast cancers treated solely by irradiation, after insufficient dissection, and for large tumors not amenable to primary surgery. When the nodal region is treated by surgery and/or radiotherapy, local monitoring with US appears unnecessary owing to the low incidence of nodal recurrence.     

乳腺癌前哨淋巴结活检技术的临床应用

目的:探讨前哨淋巴结活检(Sentinel lymph node biopsy,SLNB)在乳腺癌外科中的应用,并评价其准确性及可行性.方法:对2002-01～2004-01我院收治的161例Ⅰ、Ⅱ期乳腺癌病例,在常规行乳腺癌手术前均进行SLNB,即肿瘤局部皮内联合注射99mTc-DX及美蓝,根据核素示踪及美蓝染色结果寻找SLN并摘除,行冰冻病理检查.将SLNB结果与术后腋窝淋巴结病理结果进行分析.结果:161例中149例发现SLN,检出率为92.5%(149/161);共检出SLN273个,平均1.83个/例.比较SLNB与术后病理结果,SLNB检出灵敏度为96.1%(49/51),准确性98.7%(147/149),假阴性率3.9%(2/51),假阳性率0。结论:SLN可比较准确地反映腋窝淋巴结状况,SLNB是乳腺癌治疗中的实用技术.     

Impact of axillary nodal metastases on lymphatic mapping and sentinel lymph node identification rate in patients with early stage breast cancer

Purpose The aim of this study was to define the impact of the presence of axillary nodal metastases on lymphatic mapping and sentinel lymph node (SLN) identification rate in patients with early breast cancer.Methods Two hundred and forty-six lymphatic mapping procedures were performed with both labelled nanocolloid and blue dye, followed by SLN biopsy and/or complete axillary dissection. The following parameters were recorded: patients age, tumour laterality and location, tumour size, tumour histology, tumour stage, tumour grade, lymphovascular invasion, radiotracer injection site (subdermal–peritumoural/peri-areolar), SLN visualisation at lymphoscintigraphy, SLN metastases (presence/absence, size) and other axillary metastases (presence/absence, number). Discriminant analysis was used to analyse the data.Results SLNs were identified by labelled nanocolloid alone in 94.7% of tumours, by blue dye alone in 93.5% and by the combined technique in 99.2%. Discriminant analysis showed the gamma probe SLN identification rate to be significantly limited by the presence of axillary nodal metastases. In particular, the size of SLN metastases and the number of other axillary metastases were the most important variables in reducing the gamma probe SLN identification rate (p=0.004 and p=0.002, respectively). On the other hand, high tumour grade was the only parameter limiting the blue dye SLN identification rate.Conclusion The accuracy of lymphatic mapping with labelled nanocolloid is limited by the presence of axillary nodal metastases, and particularly by the degree of SLN tumoural invasion and the presence and number of other axillary nodal metastases. Neither of these elements seems to interfere with the blue dye identification rate. The combination of the two tracers maximises the SLN identification rate.     

Sentinel node biopsy in breast cancer

In breast cancer, sentinel node biopsy (SNB) has replaced diagnostic axillary clearance (AC) in nodal staging in numerous breast surgery units all over the world. However, there is no international standard in imaging, harvesting, and histological examination of the sentinel nodes. SNB has been validated in nodal staging of small, unifocal, clinically axillary-node-negative tumors, with a false-negative rate of approximately 5% of all axillary-node-positive cases. Despite the false-negative results, the method is assumed to provide accurate nodal staging, revealing metastases that remain undetected in AC. Furthermore, clinically overt axillary metastases have been rare when omitting AC relying on tumor-negative sentinel node findings, at least during a short follow-up. SNB is associated with faster recovery and less long-term morbidity than AC. Although the results of the large randomized trials have still to come, SNB has become the standard of care in early breast cancer.     

Lymphatic mapping and retrieval of the sentinel lymph node in treatment of early breast cancer

Lymphatic mapping and sentinel lymph node biopsy is an important step to surgical individualization of breast cancer therapy. With lymphatic mapping and minimally invasive biopsy of one or two detected lymph nodes the method provides an exact evaluation of the nodal status. Using sentinel lymph node biopsy (SLNB), costs and morbidity of an axillary lymph node dissection (ALND) can be avoided in nodal negative patients, whereas nodal positive patients are chosen for ALND very selectively according to the detection of an increased percentage of micrometastases. While experienced centers are introducing this method into clinical practice for the benefit of patients with early-stage breast cancer in Europe, further research should focus on quality control, definition of standards considering the individual needs of the individual patient, and the evaluation of the impact of micrometastases. This article gives an overview of the current knowledge of SLNB and discusses critically current indications and methods as well as application techniques.     

Axillary lymph node metastases: a statistical analysis of various parameters in MRI with USPIO

PURPOSE: To assess the value of plain vs. iron oxide-enhanced MRI vs. the combined study (plain + postcontrast) based on qualitative and quantitative parameters of three pulse sequences. MATERIALS AND METHODS: Data from two sites were acquired using the same technique; therefore, this data could be pooled. T1W-SE, T2W-FSE, and 3D-PSIF were used before and 24-36 hours after MRI with ultra small particles of iron oxide (USPIO) was performed. A total of 52 lymph nodes (LNs) in nine patients (25 benign, 27 malignant) were evaluated by two readers who were visually and quantitatively blinded to the histology. Combinations of the following diagnostic parameters were compared using logistic regression analysis: the short-axis diameter of the LN, the signal distribution of the LN on postcontrast agent MRI (homogeneous or heterogeneous), and qualitatively and quantitatively determined signal changes of the LN following administration of contrast agent in the three evaluated sequences. RESULTS: Using pre- and postcontrast data, the optimized accuracy based on the statistically most significant parameters (LN diameter > 6 mm, visual assessment of signal change on T2W-SE) was 87% (81% sensitivity, 92% specificity). Precontrast data alone yielded 75% accuracy (63% sensitivity, 86% specificity). Postcontrast data alone yielded 75% accuracy (56% sensitivity, 96% specificity). CONCLUSION: Based on our results, USPIO-MRI improved the diagnosis of metastatic axillary LNs compared with precontrast MRI alone. Both pre- and postcontrast studies are needed. T1W-SE and T2W-PSIF did not yield significant additional information. This study may help to further improve the technique of USPIO imaging.     

基于CT增强图像的影像组学模型评估乳腺癌腋窝淋巴结转移

目的:探讨基于CT增强图像的影像组学在评估乳腺癌腋窝淋巴结转移方面的临床应用价值.方法:回顾性分析402例乳腺癌患者(共825枚短径≥5 mm腋窝淋巴结)的CT增强图像.在每个淋巴结的最大层面勾画ROI,使用AK软件提取淋巴结的纹理特征.对两位医师分别提取的100个淋巴结的纹理特征进行一致性分析.分别采用单因素方差分析...     

Detection of lymph node metastases by contrast-enhanced MRI in an experimental model.

Lymph node size, the accumulation of a nodal lymphotrophic contrast agent (LCDIO), and MRI were compared as methods for detecting nodal metastases in an experimental murine model. Lymph node metastases (B16-F1 melanoma expressing green fluorescent protein (GFP) and C57BL/6 mice) were generated to obtain a wide spectrum of nodes, including normal nodes and nodes bearing micrometastases, small metastases, or large metastases. Nodal uptake of LCDIO was measured using (111)Indium-labeled LCDIO and was found to be lower in micrometastastic nodes (4.20 +/- 1.4%ID/gm) than in normal nodes (8.60 +/- 0.22% ID dose/gram, P < 0.005). Nodal tumor burden was quantified from the amount of GFP present in nodes measured using the Western blot method, and was found to correlate with the decrease of LCDIO uptake. By MRI, nodes bearing small and large metastases contained regions of high signal intensity (SI) that corresponded to the visual pattern of tumor in nodes. Micrometastatic nodes were distinguishable from normal nodes based on a diffuse pattern of inhomogeneous SI. The signal-to-background ratio (SBR) of normal nodes (0.0112 +/- 0.0061) was different from micrometastatic nodes (0.179 +/- 0.080, P < 0.00046) and nodes bearing small metastases (0.723 +/- 0.269, P < 0.00013), with high degrees of significance.     

Ex vivo MRI of axillary lymph nodes in breast cancer

Purpose

To provide a strategy for precise co-localization of lymph nodes on axillary lymph-node dissection (ALND) specimens both on pathology and MR.To identify nodal features suggestive of metastatic involvement on a node-to-node basis.

Materials and methods

National Institutional review-board approved this prospective study of 18 patients with breast cancer referred for ALND. Ex vivo T1 and inversion recovery (IR) T2 WI of ALND specimens tightly positioned within scaled plastic cranes was performed immediately after surgery. The correspondence of MR-based or pathologically based nodes location was assessed. The MR size and morphological presentation of metastatic and normal nodes were compared (Student's t-test or Mann–Whitney test). Quantitative variables were compared using Pearson coefficient.

Results

207 nodes were retrieved on pathology and 165 on MR. MR–pathological correlation of nodes location was high regarding MR-identified nodes (r = 0.755). An MR short axis threshold of 4 mm yielded the best predictive value for metastatic nodal involvement (Se = 78.6%; Sp = 62.3%). Irregular contours (Se = 35.7%; Sp = 96.7%), central nodal hyper-intensity on IR T2 WI (Se = 57.1%; Sp = 91.4%), and a cortical thickness above 3 mm (Se = 63.6%; Sp = 83.2%) were significantly associated with metastatic involvement.

Conclusion

Ex vivo MR allows node-to-node correlation with pathology. Morphological MR criteria can suggest metastatic involvement.     

Cost-analysis of staging methods for lymph nodes in patients with prostate cancer: MRI with a lymph node-specific contrast agent compared to pelvic lymph node dissection or CT

The aim of this study was to compare the costs of three strategies in patients with prostate cancer in a specific setting: firstly, a strategy including MR lymphography (MRL) in which pelvic lymph node dissection (PLND) is foregone in case of a negative result. The second strategy involves computed tomography (CT) followed by a biopsy or PLND. The third strategy consists of PLND without imaging beforehand. A decision analytic model was constructed. This model represented the diagnostic process for patients with prostate cancer and intermediate or high risk for nodal metastases, comparing the costs of the three strategies. Cost analysis was done from the health care perspective. The model indicated that the expected costs for the MRL strategy were €2,527. The expected costs for the strategy using CT were €3,837 and for PLND €3,994. These results show that potential savings performing MRL instead of CT were €1,310 and €1,467 for PLND. Sensitivity analyses show that variation in costs of PLND was most influential on the costs of all strategies. However, the overall savings pattern did not alter. Average costs of MRL staging in our institution are less than for CT and PLND in staging lymph nodes of patients with prostate cancer and who are intermediate or high risk for nodal metastases.     

基于T2WI-FS的影像组学特征在术前预测乳腺癌腋窝淋巴结转移中的价值

目的：探讨基于T2加权成像压脂序列（T2-weighted imaging fat suppression,T2WI-FS）图像的影像组学特征所构建机器学习模型在术前预测乳腺癌患者腋窝淋巴结（axillary lymph nodes,ALN）转移中的价值。方法：回顾并分析经病理学检查证实的乳腺癌患者68例,共171枚ALN（转移101枚,非转移70枚）。在T2WI-FS图像上勾画每个目标淋巴结的三维容积感兴趣区（volume of interest,VOI）,并提取一阶统计量特征、几何形状及纹理特征等影像组学特征。随机将两组ALN分为训练集和验证集（8∶2）,采用K最佳和最小绝对收缩和选择算子（the least absolute shrinkage and selection operator,LASSO）算法对训练集特征降维以筛选出关键特征,最后建立基于K近邻（K-nearest neighbor,KNN）、支持向量机（support vector machine,SVM）和逻辑回归（logistic regression,LR）3种分类器的机器学习模型。采用受试者工作特征（rec...     

Static and dynamic MRI of a urinary control intra-vaginal device

The aim of this study was to describe by MRI, in dynamic conditions at rest and straining, the anatomical modifications induced by a commercially available intravaginal device (IVD) aimed at relieving female stress urinary incontinence. Ten female patients complaining of stress urinary incontinence (SUI) had pelvic MRI with static and dynamic sequences, without and with a self-inserted IVD. We studied positions and angulations of the IVD in the pelvis. Paired t-test allowed comparisons of: position of the bladder neck; urethral angulation with the pubis axis; position of the urethra; and posterior urethro-vesical angle (PUVA) without and with IVD. At rest, in ten of ten cases IVD laid cranial to the pubo-rectal muscle; with an average angulation of 95 ± 10 ° with the pubis axis, laterally tilted in three of ten cases. In maximum straining with IVD bladder neck descent was lower by an average of 5.2 ± 3.1 mm (p = 0.001), pubo-urethral angle opening was smaller by an average of 22 ± 20 °(p = 0.015), and bladder neck to pubis distance was shorter by an average of 5.7 ± 4 mm. Posterior urethro-vesical angle was not significantly modified. Dynamic MRI allowed a non-invasive assessment of the mode of action of an IVD. The main modifications were a support of the bladder base and bladder neck, with a superior displacement of the urethra toward the pubis. Received: 6 October 1999; Revised: 17 January 2000; Accepted: 18 January 2000     

Sentinel node in breast cancer procedural guidelines

Content Procedure guidelines for scintigraphic detection of sentinel node in breast cancer are presented. Authors The paper was written by several experts in this field on behalf of the European Association of Nuclear Medicine Oncology and Dosimetry committees and approved by the Executive Committee. An Editorial commentary on this paper is available at . Disclaimer: The European Association of Nuclear Medicine has written and approved guidelines to promote the cost-effective use of high-quality nuclear medicine procedures. These generic recommendations cannot be rigidly applied to all patients in all practice settings. The guidelines should not be deemed inclusive of all proper procedures or exclusive of other procedures reasonably directed to obtaining the same results. Advances in medicine occur at a rapid rate. The date of a guideline should always be considered in determining its current applicability. All authors declare they have no conflict of interest.     

前哨淋巴结阳性乳腺癌患者腋窝转移危险因素的研究

目的研究前哨淋巴结（sentinellymphnode,SLN）阳性乳腺癌患者腋窝非前哨淋巴结（NSI-N）转移的危险因素,验证纪念斯隆一凯特琳癌症中心（MSKCC）腋窝NSLN转移预测模型评估乳腺癌患者的临床应用价值。方法回顾性地分析军事医学科学院附属医院普外科2000年,11月至2011年3月175例成功行SLN活检且结果阳性、随即行腋窝淋巴结清扫的乳腺癌患者临床病理资料,使用MSKCC预测模型计算每例患者腋窝NSLN转移风险,利用校正曲线和受试者操作特性曲线（ROC）下面积（AUC）评估该模型预测的准确性。结果原发肿瘤大小、肿瘤是否多发、阳性SLN数、阳性SLN转移率、阴性SLN数与腋窝NSLN转移相关,P值分别为0．0018、0．0029、0．0049、0．0007、0．0002。多因素Logistic回归分析发现,原发肿瘤大小、肿瘤是否多发和阳性SI．N数是NSI．N转移的独立危险因素,P值分别为0．0022、0．0160、0．0176。校正曲线显示预测值曲线和真实值曲线趋势相近,MSKCC预测模型被验证的AUC值为0．79。结论对于SLN转移阳性的乳腺癌患者,原发肿瘤越小、肿瘤单发、阳性SLN数越少、阴性SLN数越多、阳性SLN转移率越低,其腋窝NSLN转移可能性越低,可对是否行腋窝淋巴结清扣提供参考。MSKCC预测模型可较准确地预测腋窝NSI．N的转移风险。     

Cystic lymph node enlargement of the neck: filariasis as a rare differential diagnosis in MRI

Cervical lymph node enlargement is a common feature of most inflammatory and neoplastic entities of the head and neck. Filariasis can lead to lymphangiectasis resembling lymph node enlargement; however, this is a rare differential diagnosis in European patients. As ethnic minorities are increasing throughout Europe and personal mobility, e.g. during holidays, is increasing, such rare differential diagnoses have to be taken into consideration. We present the case of an Iraqi patient referred to as for a suspected cystic lymph node mass that was verified histologically by open MRI biopsy and proved to be a cystic manifestation of filariasis.     

乳腺癌腋窝淋巴结影像诊断研究进展

乳腺癌目前是全球女性发病率最高的恶性肿瘤,严重威胁着患者的健康。腋窝淋巴结情况对乳腺癌早期诊断,手术和预后评价等临床决策至关重要。影像学诊断技术飞速发展,在临床上的应用越来越广泛。本文就乳腺癌腋窝淋巴结影像诊断研究进展予以综述。     

基于乳腺X线图像影像组学列线图对乳腺癌腋窝淋巴结转移的预测价值

目的:探讨基于乳腺X线图像影像组学列线图对乳腺癌腋窝淋巴结(ALN)转移的预测价值.方法:回顾性分析188例乳腺癌患者的乳腺X线图像和临床资料,按照7:3的比例将患者随机分割为训练组(n=130)和验证组(n=58).使用MaZda软件在乳腺X线图像内提取影像组学特征,应用方差选择法和最小绝对收缩与选择算子算法(LAS...     

乳腺癌动态增强MRI表现与腋窝淋巴结转移及ER、PR的关系

目的 探讨乳腺癌MRI表现与腋窝淋巴结转移及雌激素受体(estrogen receptor,ER)、孕激素受体(progester-one receptor,PR)的关系.方法 选取我院乳腺癌患者83例,根据患者有无腋窝淋巴结转移、病理类型、ER、PR表达情况进行分组,分析增强MRI表现与其之间的关系.结果 有腋窝淋巴...