Ethical issues in contrast-enhanced magnetic resonance imaging screening for breast cancer

Breast magnetic resonance imaging (MRI) screening has been shown to detect early breast cancer. The main challenge ahead for breast MRI screening is to prove its effectiveness in reducing breast cancer mortality. While this challenge is commonly viewed as a scientific, technological, and clinical one, it also carries ethical components. This article is concerned with the risks and benefits of MRI screening that should be explained to screening participants and discusses the evidence needed by policy makers who ultimately will determine a just allocation of health care resources to MRI breast cancer screening.     

Screening for breast cancer with MRI

Breast MRI has emerged as an extremely powerful tool in breast imaging. The use of breast MRI for cancer detection has the potential to change our current algorithms in the detection of breast cancer. By being able to detect cancer that is occult on conventional imaging, such as mammography and sonography, MRI can detect early breast cancer that was previously unseen by conventional imaging. This article reviews the experience of screening breast MRI in the high-risk population. It also reviews the limitations associated with its use. Before breast MRI can be used in the clinical setting, an ability to localize or biopsy MRI detected lesions that are occult on mammography and ultrasound is needed and must be available for these patients. Although the robustness of this technique has generated considerable enthusiasm, our perspective should be tempered by the fact that many questions remain unanswered regarding the use of breast MRI for screening in the nonhigh risk population as well as integration of breast MRI into clinical practice.     

High-resolution MR imaging of the breast

Investigation into the use of MRI as a breast imaging tool is ongoing. Several studies have shown that MRI is a very accurate imaging method for the identification of implant failure in the symptomatic patient with augmented breasts. In this clinical setting, MRI may be the study of choice. Imaging techniques, and the MRI appearance of normal and abnormal implants, are described. The use of MRI for the detection of breast cancer is not as straightforward. Preliminary results suggest that this technique can be used as an adjunct to mammography for the detection and diagnosis of breast cancer. However, it is premature to draw firm conclusions regarding the role that MRI should play in the management of women with breast disease because of the wide variability of imaging techniques, protocols, and patient populations in the studies reported to date. In this overview, the current state of MR imaging of the breast is discussed. Technical requirements are described, and potential clinical applications—including the differentiation of benign from malignant lesions, breast cancer staging, detection of recurrence after breast conservation therapy, and detection of cancer in patients presenting with positive axillary lymph nodes with an unknown primary—are reviewed. Many of these potential clinical applications will require an accurate MR-guided biopsy system, and the implementation of such a system as well as its inherent limitations are discussed.     

乳腺癌化疗相关认知损害神经影像标志物的研究进展

神经影像技术特别是MRI在评估脑解剖结构及功能变化等方面应用广泛,已逐渐成为临床研究乳腺癌化疗相关认知损害(chemotherapy-related cognitive impairment,CRCI)的有力工具,并为其早期诊断提供了客观的影像诊断标志物。本文就神经影像方法在乳腺癌CRCI神经影像标志物研究中的应用进展进行文献综述,以期为揭示其病理生理机制及早期诊断研究提供影像学依据。     

乳腺MRI检查对乳腺癌个体化治疗的作用

乳腺MRI具有极好的软组织分辨率和无射线辐射特点,对乳腺癌诊断和局部分期明显优于X线和超声检查,本文结合临床病例在四个方面重点阐述乳腺MRI检查对乳腺癌个体化治疗的作用.     

多参数乳腺MRI技术的研究现状及潜力

磁共振成像(magnetic resonance imaging,MRI)是乳腺疾病诊断中必不可少的工具,尤其是乳腺功能成像在鉴别良恶性乳腺肿块中发挥重要价值.动态对比增强MRI可以提供乳腺肿瘤组织灌注等相关功能信息,提高了乳腺癌诊断的敏感度.扩散加权成像可以反映水分子的运动情况,研究表明扩散功能图如表观扩散系数、体素...     

超声和MRI影像学及影像组学在乳腺癌中的研究进展

乳腺癌是全球女性最常见的恶性肿瘤之一,发病率和致死率居癌症首位,早期诊断和早期治疗可以提高疾病预后效果,降低疾病相关死亡率。超声和MRI影像学是乳腺癌诊疗指南推荐对原发肿瘤评估无创检查方式,随着科技的发展,越来越多的影像学新技术应用于临床实践,乳腺癌检出率和诊断准确率都有了很大提高。人工智能的出现,拓展了影像组学的应用,推动了乳腺癌精准医疗的发展。本文针对超声和MRI影像学及影像组学在乳腺癌临床诊疗中的应用进展进行了综述。      

多参数MRI在乳腺癌诊疗中的应用及进展

多参数核磁共振成像（MRI）在乳腺癌诊疗过程中具有重要作用。随着乳腺MRI的不断发展,越来越多的功能学参数提供了更多定量指标,为乳腺癌筛查、诊断、疗效评估及预后提供更多信息。本文从乳腺MRI检查设备、检查序列、临床检查适应证及MRI的新技术、新进展等方面介绍多参数MRI在乳腺癌诊疗过程中的应用及进展。     

Future applications and innovations of clinical breast magnetic resonance imaging

Magnetic resonance imaging (MRI) of the breast has become a valuable diagnostic tool for detecting and evaluating breast abnormalities. Breast MRI is rapidly advancing, and several innovations have strong implications for improved detection, diagnostic accuracy, and treatment monitoring. This article describes select areas of recent technical development that are likely to have an increasing clinical impact on MRI of the breast, including high-field imaging, parallel imaging, high-sensitivity breast coils, diffusion-weighted imaging, and magnetic resonance spectroscopy.     

An RF breast coil for 0.2T MRI

Breast cancer is the most frequently diagnosed cancer in women. High field studies have shown the diagnostic value of breast MRI, but the examination costs greatly exceed those of competing conventional mammography. Low field MRI offers typical MRI contrast at substantially lower cost, but has suffered from lower spatial resolution. Specificity of breast MRI can potentially be increased by acquiring MR imaging with higher spatial or temporal resolution, but the signal‐to‐noise ratio (SNR) achievable in a given imaging time becomes limiting. SNR for the particular pulse sequence and magnet field strength is strongly influenced by the characteristics of the radio‐frequency coil. An optimal breast coil should yield excellent SNR but also generate a homogeneous B₁ field, while allowing imaging of the both breasts simultaneously and maintaining patient comfort. RF receiver coil design is a key determinant of image quality, thus to address this we have designed and constructed a low field breast imaging coil. The coil was tested with a 4‐post 0.2T MRI providing high quality breast images. Designed and constructed saddle rf coil allows to obtain good quality image of the breast using low 0.2 T MRI system within 2 minutes. The coil provides patient comfort as breast compression is not required and minimizes artefacts caused by respiration or motion. A high contrast, low‐cost and pain‐free breast examination using optimized low field MRI system has the potential to serve a large patient population for whom current technologies have deficiencies. © 2015 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 46B: 3–7, 2016     

The utility of MRI for the screening and staging of breast cancer

INTRODUCTION & BACKGROUND: Contrast-enhanced magnetic resonance imaging (MRI) of the breast has been recently introduced as a potential clinical tool for the detection, diagnosis, staging and management of breast cancer. In this article, we consider the established and evolving roles of MRI with particular reference to screening in high risk women and staging of the primary tumour. Controversies are discussed in the context of the tumour biology and natural history of breast cancer. METHODS: Articles were identified by searches of PubMed and MEDLINE up to October 2007. RESULTS: Contrast-enhanced MRI is an effective tool for screening women at high risk of breast cancer. However, randomized trials have yet to demonstrate a reduction in mortality. MRI can also facilitate local staging, in particular, the evaluation of ipsilateral multicentric or multifocal lesions and synchronous contralateral disease which may be 'missed' by conventional imaging. However, efficacy with respect to clinically relevant and patient oriented end-points has yet to be addressed in the context of clinical trials. CONCLUSIONS: In women at high risk of breast cancer, screening MRI should be used in conjunction with published guidelines. In women with newly diagnosed breast cancer, the utility of MRI is less clearly defined and should be restricted to selected cases within the multidisciplinary setting.     

不同影像学技术引导下乳腺癌穿刺活检研究进展

早发现、早诊断是提高乳腺癌疗效的关键,早期乳腺癌往往不具备典型临床症状和体征。影像学检查可发现临床无法触及的肿块,通过影像学技术引导定位活检现已成为诊断乳腺癌的重要工具。目前乳腺癌影像学检查方法主要包括乳腺超声、乳腺X线摄影、MR及锥束乳腺CT。本文就影像学技术引导定位穿刺活检诊断乳腺癌的进展进行综述。     

扩散加权成像表观扩散系数在乳腺癌中的应用进展

Breast cancer has become the most common cancer in Chinese women, and breast magnetic resonance imaging (MRI) has become increasingly important in the diagnosis of breast diseases. MRI has high sensitivity in the diagnosis of breast cancer, but lack specificity. As an important supplementary technique for breast MRI, diffusion weighted imaging (DWI) can improve the specificity and has been widely used in clinic. Apparent diffusion coefficient (ADC) is a measure of the diffusion of water molecules in tissues, which can be calculated using diffusion-weighted images. DWI-ADC value becomes a hot topic in the differentiating benign and malignant breast lesions and evaluating the prognosis, metastasis risk and chemotherapy efficacy of breast cancer. Building upon recent surveys of this field, this article reviews the basic principle, application progress, limitation and prospect of DWI-ADC.      

Comparison between dynamic cystocolpoproctography and dynamic pelvic floor MRI: pros and cons: Which is the “functional” examination for anorectal and pelvic floor dysfunction?

“Functional” imaging of anorectal and pelvic floor dysfunction has assumed an important role in the diagnosis and management of these disorders. Although defecography has been widely practiced for decades to evaluate the dynamics of rectal emptying, debate concerning its clinical relevance, how it should be done and interpreted continues. Due to the recognition of the association of defecatory disorders with pelvic organ prolapse in women, the need to evaluate the pelvic floor as a unit has arisen. To meet this need, defecography has been extended to include not only evaluation of defecation disorders but also the rest of the pelvic floor by opacifying the small bowel, vagina, and the urinary bladder. The term “dynamic cystocolpoproctography” (DCP) has been appropriately applied to this examination. Rectal emptying performed with DCP provides the maximum stress to the pelvic floor resulting in complete levator ani relaxation. In addition to diagnosing defecatory disorders, this method of examination demonstrates maximum pelvic organ descent and provides organ-specific quantification of organ prolapse, information that is only inferred by means of physical examination. It has been found to be of clinical value in patients with defecation disorders and the diagnosis of associated prolapse in other compartments that are frequently unrecognized by history taking and the limitations of physical examination. Pelvic floor anatomy is complex and DCP does not show the anatomical details pelvic magnetic resonance imaging (MRI) provides. Technical advances allowing acquisition of dynamic rapid MRI sequences has been applied to pelvic floor imaging. Early reports have shown that pelvic MRI may be a useful tool in pre-operative planning of these disorders and may lead to a change in surgical therapy. Predictions of hypothetical increase cancer incidence and deaths in patients exposed to radiation, the emergence of pelvic floor MRI in addition to questions relating to the clinical significance of DCP findings have added to these controversies. This review analyses the pros and cons between DCP and dynamic pelvic floor MRI, addresses imaging and interpretive controversies, and their relevance to clinical management.     

Imaging of the breast

A multitude of techniques for imaging and evaluating the breast have been described. Based upon current evidence, thermography does not appear to have any established clinical indications. Computed tomography, ultrasonography, lightscanning, and NMR may be useful as adjuncts to mammography, and further research seems warranted. Mammography remains the "gold standard" in breast imaging, however. Its ability to detect clinically occult disease makes it the superior imaging technique in the breast, and the only technique indicated for screening. In light of the information presented in this article, it is hoped that the trend away from mammography in favor of so-called "noninvasive" breast imaging techniques will be reversed until such time that the efficacy of these other modalities has been proven. A proper process for the evaluation and clinical testing of the newer breast imaging modalities has been defined. Using this as a guideline, it is hoped that the indiscriminate clinical use of unproven techniques will be avoided.     

Prostate cancer: value of magnetic resonance spectroscopy 3D chemical shift imaging

The results of recent studies of magnetic resonance imaging (MRI) combined with three-dimensional magnetic resonance spectroscopic imaging (3D-MRSI) demonstrate that the MRI/3D-MRSI exam is a unique method by which to noninvasively study the cellular metabolism and anatomy of the prostate. 3D-MRSI is emerging as the most specificity tool for non-invasive evaluation of the prostate cancer. The results of current MRI/3D-MRSI studies also provide evidence that the magnitude of metabolic changes in regions of cancer before therapy, as well as the extent of the time course of metabolic changes after therapy, may improve our understanding of cancer aggressiveness. Assessment of cancer spread outside the prostate can be significantly improved by combining MRI findings with estimates of metabolic abnormalities provided by 3D-MRSI. Clinically, combined MRI/3D-MRSI has already demonstrated a potential for improved diagnosis, staging, and treatment planning for patients with prostate cancer. This article reviewed the value of 3D-MRS imaging for the diagnosis, localization, staging, aggressiveness, and treatment planning of prostate cancer.     

乳腺癌MRI影像组学的研究进展

乳腺癌是全世界女性最常见的恶性肿瘤之一,也是患癌女性的主要死因。提高诊断准确性、早期评估乳腺癌预后及治疗效果是临床实践中的关键问题。MRI因其较高的软组织分辨率,目前仍是诊断乳腺癌的常用成像方式。相对于乳房X线摄影和超声,MRI可以提供更全面的诊断信息。影像组学是一个高通量提取和定量分析影像特征的新研究领域,近年来受到广泛关注并应用于肿瘤领域。作者就乳腺癌MRI影像组学方面的研究进展进行综述。     

Cancer staging with breast MR imaging

Breast MR imaging is a useful tool for staging breast cancer patients, and staging is more accurate with MR imaging than with conventional imaging techniques. MR imaging is the preferred imaging test for the accurate staging of breast cancer before surgery and for assessment of patients with positive axillary adenopathy and negative mammogram and physical examination. There are many important questions regarding the role of MR imaging in breast cancer staging that must be addressed by future research and involvement of MR imaging of the breast in clinical trials.     

Clinical and radiological manifestations of the rheumatoid wrist. A comprehensive review

OBJECTIVE: The intent of this review article is to present the common clinical and radiological features of the rheumatoid wrist as seen in everyday practice. Imaging of the rheumatoid wrist is discussed with emphasis on magnetic resonance imaging (MRI) and its current and future role in the diagnosis and treatment follow-up of the disease. DATA SOURCE: A search of the current medical literature from 1990 to present through PubMed was performed without constraints. Search terms used included: MRI, rheumatoid arthritis, wrist, treatment, diagnosis, radiology, clinical manifestations, and incidence. STUDY SELECTION: The articles included in this review were selected by historical significance, date of publication, pertinent review information, and, most specifically, those articles studying the current uses for imaging the rheumatoid wrist. DATA SYNTHESIS: This review demonstrated an overall agreement between numerous studies that the usefulness of MRI evaluation of the rheumatoid wrist is in its early stages of development. Many of the features of this examination of the wrist are discussed and contrasted with plain film radiographic examination. RESULTS: The role of the clinician in the diagnosis and treatment, including complementary care, as well as the follow-up of rheumatoid arthritis in the wrist is unquestionable. The role of plain film examination as a diagnostic tool is excellent. The current and future role of MRI of rheumatoid arthritis is becoming obvious and will likely become the diagnostic imaging tool of choice in the near future. CONCLUSION: MRI provides more specific information on rheumatoid lesions in the wrist than plain film imaging. This is especially true when intravenous contrast is utilized. The clinician's use of physical examination, laboratory examination, radiography, and MRI will provide for early diagnosis, treatment, and follow-up of RA in the wrist.     

A genetic signature can predict prognosis and response to therapy in breast cancer: Oncotype DX

We now recognize that not all breast cancers are the same. Different characteristics in gene expression profiles result in differential clinical behavior. With the use of gene microarrays, different subtypes of breast cancer have been characterized. These subtypes include the basal, the ERBB2+, and the luminal A, B and C subtypes. The importance of these different subtypes lies in the fact that they differ in clinical outcome, with the basal and ERBB2+ subtypes having the worst prognosis and the luminal A group having the best prognosis. However, identification of these subtypes is still not clinically used. Other strategies for evaluating tumors in a clinical setting have been developed using smaller sets of genes. One such strategy is the 21-gene assay (Oncotype DX), which is currently in commercial use in the USA. One advantage of this test is the use of paraffin-embedded blocks instead of previous methods, which required fresh frozen tissue. Oncotype DX has been shown to predict 10-year distant recurrence in patients with estrogen receptor-positive, axillary lymph node-negative breast cancer. This genomic assay has also been shown to predict chemotherapy and endocrine therapy response. Large, prospective, randomized clinical trials are currently underway using this genomic test. Other similar tests are also finding their way in clinical practice. A 70-gene assay, which has been developed by a group in The Netherlands, is currently being used as a tool to assign treatment in women with early stage breast cancer. In the near future, clinical decisions will most likely be dictated by the genetic characteristics of the tumor, with the clinical characteristics becoming less important. Tailoring our treatment based on individual tumor characteristics will help us develop better therapeutic strategies and save many of our patients from receiving unnecessary toxic therapy.