Active surveillance of renal masses, which includes serial imaging with the possibility of delayed treatment, has emerged as a viable alternative to immediate therapeutic intervention in selected ...patients. Active surveillance is supported by evidence that many benign masses are resected unnecessarily, and treatment of small cancers has not substantially reduced cancer-specific mortality. These data are a call to radiologists to improve the diagnosis of benign renal masses and differentiate cancers that are biologically aggressive (prompting treatment) from those that are indolent (allowing treatment deferral). Current evidence suggests that active surveillance results in comparable cancer-specific survival with a low risk of developing metastasis. Radiology is central in this. Imaging is used at the outset to estimate the probability of malignancy and degree of aggressiveness in malignant masses and to follow up masses for growth and morphologic change. Percutaneous biopsy is used to provide a more definitive histologic diagnosis and to guide treatment decisions, including whether active surveillance is appropriate. Emerging applications that may improve imaging assessment of renal masses include standardized assessment of cystic and solid masses and radiomic analysis. This article reviews the current and future role of radiology in the care of patients with renal masses undergoing active surveillance.
The Bosniak classification attempts to predict the likelihood of renal cell carcinoma (RCC) among cystic renal masses but is subject to interobserver variability and often requires multiphase ...imaging. Artificial intelligence may provide a more objective assessment. We applied computed tomography texture-based machine learning algorithms to differentiate benign from malignant cystic renal masses.
This is an institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study of 147 patients (mean age, 62.4 years; range, 28-89 years; 94 men) with 144 cystic renal masses (93 benign, 51 RCC); 69 were pathology proven (51 RCC, 18 benign), and 75 were considered benign based on more than 4 years of stability at follow-up imaging. Using a single image from a contrast-enhanced abdominal computed tomography scan, mean, SD, mean value of positive pixels, entropy, skewness, and kurtosis radiomics features were extracted. Random forest, multivariate logistic regression, and support vector machine models were used to classify each mass as benign or malignant with 10-fold cross validation. Receiver operating characteristic curves assessed algorithm performance in the aggregated test data.
For the detection of malignancy, sensitivity, specificity, positive predictive value, negative predictive value, and area under the curve were 0.61, 0.87, 0.72, 0.80, and 0.79 for the random forest model; 0.59, 0.87, 0.71, 0.79, and 0.80 for the logistic regression model; and 0.55, 0.86, 0.68, 0.78, and 0.76 for the support vector machine model.
Computed tomography texture-based machine learning algorithms show promise in differentiating benign from malignant cystic renal masses. Once validated, these may serve as an adjunct to radiologists' assessments.
Cystic renal masses are commonly encountered in clinical practice. In 2019, the Bosniak classification of cystic renal masses, originally developed for CT, underwent a major revision to incorporate ...MRI and is referred to as the Bosniak Classification, version 2019. The proposed changes attempt to
define renal masses (ie, cystic tumors with less than 25% enhancing tissue) to which the classification should be applied;
emphasize specificity for diagnosis of cystic renal cancers, thereby decreasing the number of benign and indolent cystic masses that are unnecessarily treated or imaged further;
improve interobserver agreement by defining imaging features, terms, and classes of cystic renal masses;
reduce variation in reported malignancy rates for each of the Bosniak classes;
incorporate MRI and to some extent US; and
be applicable to all cystic renal masses encountered in clinical practice, including those that had been considered indeterminate with the original classification. The authors instruct how, using CT, MRI, and to some extent US, the revised classification can be applied, with representative clinical examples and images. Practical tips, pitfalls to avoid, and decision tree rules are included to help radiologists and other physicians apply the Bosniak Classification, version 2019 and better manage cystic renal masses. An online resource and mobile application are also available for clinical assistance.
RSNA, 2021.
Technologic advances in both computed tomography (CT) and magnetic resonance (MR) imaging have resulted in the ability to image the urinary tract in ways that surpass the prior mainstay of urinary ...tract imaging, the intravenous urogram. In adults, for most, if not all, historical indications for intravenous urography, CT urography or MR urography is now the preferred examination. Although a variety of techniques for both examinations have been described, each test provides more diagnostic information than does intravenous urography. With the introduction of multidetector technology, CT urography, to date, has emerged as the initial heir apparent to intravenous urography; many years of experience have now clearly demonstrated that CT is the test of choice for many urologic problems, including urolithiasis, renal masses, urinary tract infection, trauma, and obstructive uropathy. CT urography provides a detailed anatomic depiction of each of the major portions of the urinary tract--the kidneys, intrarenal collecting systems, ureters, and bladder--and thus allows patients with hematuria to be evaluated comprehensively. MR urography can be used also to evaluate the urinary tract and has the advantage of not using ionizing radiation and the potential to provide more functional information than CT. However, MR urography is less established and less reliably results in diagnostic image quality relative to CT urography. Although both tests can be used to evaluate the urinary tract, several issues remain and include reaching a consensus on the optimal protocols and appropriate utilization in an era of cost containment and heightened concerns about radiation exposure.
Management of the incidental renal mass Silverman, Stuart G; Israel, Gary M; Herts, Brian R ...
Radiology,
10/2008, Letnik:
249, Številka:
1
Journal Article
Recenzirano
Despite substantial advances in the imaging-based diagnosis of renal masses, the increased detection of incidental renal masses with cross-sectional imaging poses problems to the radiologist and ...referring physician. Most incidental renal masses can be diagnosed with confidence and either ignored or treated without further testing. However, some renal masses, particularly small ones, remain indeterminate and require a management strategy that is both medically appropriate and practical. In this article, the literature will be reviewed and an approach to the diagnosis and management of the incidental renal mass will be suggested. Management recommendations, derived from data regarding the probability of malignancy in cystic and solid renal masses, are provided for two types of patients, those in the general population and those with limited life expectancy or co-morbidity. The Bosniak classification is used to guide the management of cystic masses, with observation reserved for selected patients, and the presumption of benignity recommended for simple-appearing cystic masses smaller than 1 cm. Among solid renal masses, a more aggressive overall approach is taken. However, additional imaging, and in selected patients, percutaneous biopsy, is recommended to diagnose benign neoplasms. Although additional studies are needed to establish risks and benefits, observation of solid masses may be considered in selected patients. Minimally invasive treatments of renal cancer (including percutaneous ablation) show promise but at the same time challenge the radiologist to review the approach to the incidental renal mass.
Abstract Objectives There is an important need to evaluate therapeutic approaches for osteoarthritis (OA) in terms of cost-effectiveness as well as efficacy. Methods The ESCEO expert working group ...met to discuss the epidemiological and economic evidence that justifies the increasing concern of the impact of this disease and reviewed the current state-of-the-art in health economic studies in this field. Results OA is a debilitating disease; it is increasing in frequency and is associated with a substantial and growing burden on society, in terms of both burden of illness and cost of illness. Economic evaluations in this field are relatively rare, and those that do exist, show considerable heterogeneity of methodological approach (such as indicated population, comparator, decision context and perspective, time horizon, modeling and outcome measures used). This heterogeneity makes comparisons between studies problematic. Conclusions Better adherence to guidelines for economic evaluations is needed. There was strong support for the definition of a reference case and for what might constitute “standard optimal care” in terms of best clinical practice, for the control arms of interventional studies.
Incidental cystic renal masses are common, usually benign, and almost always indolent. Since 1986, the Bosniak classification has been used to express the risk of malignancy in a cystic renal mass ...detected at imaging. Historically, magnetic resonance imaging (MRI) was not included in that classification. The proposed Bosniak v.2019 update has formally incorporated MRI, included definitions of imaging terms designed to improve interobserver agreement and specificity for malignancy, and incorporated a variety of masses that were incompletely defined or not included in the original classification. For example, at unenhanced MRI, homogeneous masses markedly hyperintense at T2‐weighted imaging (similar to cerebrospinal fluid) and homogeneous masses markedly hyperintense at fat suppressed T1‐weighted imaging (approximately ≥2.5 times more intense than adjacent renal parenchyma) are classified as Bosniak II and may be safely ignored, even when they have not been imaged with a complete renal mass MRI protocol. MRI has specific advantages and is recommended to evaluate masses that at computed tomography (CT) 1) have abundant thick or nodular calcifications; 2) are homogeneous, hyperattenuating, ≥3 cm, and nonenhancing; or 3) are heterogeneous and nonenhancing. Although MRI is generally excellent for characterizing cystic renal masses, there are unique weaknesses of MRI that bear consideration. These details and others related to MRI of cystic renal masses are described in this review, with an emphasis on Bosniak v.2019. A website (https://bosniak-calculator.herokuapp.com/) and mobile phone apps named “Bosniak Calculator” have been developed for ease of assignment of Bosniak classes.
Level of Evidence
5
Technical Efficacy Stage
3
The ACR Incidental Findings Committee (IFC) presents recommendations for renal masses that are incidentally detected on CT. These recommendations represent an update from the renal component of the ...JACR 2010 white paper on managing incidental findings in the adrenal glands, kidneys, liver, and pancreas. The Renal Subcommittee, consisting of six abdominal radiologists and one urologist, developed this algorithm. The recommendations draw from published evidence and expert opinion and were finalized by informal iterative consensus. Each flowchart within the algorithm describes imaging features that identify when there is a need for additional imaging, surveillance, or referral for management. Our goal is to improve quality of care by providing guidance for managing incidentally detected renal masses.
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