A pilot study of [18F]F-fluciclovine positron emission tomography/computed tomography for staging muscle invasive bladder cancer preceding radical cystectomy

AIM

To assess the ability of [18F]F-fluciclovine-PET/CT to stage muscle invasive bladder cancer (MIBC) before radical cystectomy.

METHODS

This single-site prospective pilot study enrolled patients with MIBC and T2-T4, N0 disease on CT/MRI slated to undergo radical cystectomy (RC). Dynamic and static [18F]F-fluciclovine-PET/CT images were acquired. Clinical readers assessed for confirmation of the primary bladder lesion on imaging and the presence of pelvic nodal metastases. Findings were compared to pathology at RC. Kinetic parameters from dynamic PET/CT were compared across bladder lesions of different clinical stages.

RESULTS

The study enrolled sixteen patients (median age: 73 years, range: 57-88 years, 11 males, 5 females), twelve receiving neoadjuvant chemotherapy before RC. There was high specificity amongst all three readers for detecting lymph node metastases (overall specificity: 0.91, 95%CI: 0.81-1.00) with good overall agreement rate with pathology (0.67, 95%CI: 0.44-0.83). The overall PPV for all readers for identifying node-positive disease was 0.4 (95%CI: 0-1.00), and the overall sensitivity was 0.13 (95%CI: 0-0.44). The overall PPV for detecting the primary tumor was 0.69 (95%CI: 0.47-0.88), and the sensitivity was 0.89 (95%CI: 0.78-1.00), with NPV and specificity being 0.70 (95%CI: 0.33, 1.00) and 0.39 (95%CI: 0.33, 0.50), respectively. Compartmental analysis of the primary bladder tumor revealed that k1 and vb parameters significantly differentiated between low (pT0-pT1) and high (pT2-pT4) risk disease (p < 0.05). Immunohistochemical assessment showed no significant correlation of tumor [18F]F-fluciclovine uptake nor kinetic parameter with amino acid transporter expression.

CONCLUSIONS

[18F]F-fluciclovine demonstrates good specificity and agreement rate for MIBC staging, with sensitivity like CT/MRI. Kinetic parameters such as k1 was able to delineate higher-stage ( ≥ = pT2) primary lesions. Heterogeneous amino acid transporter expression can be seen across lesions. Further studies are warranted to understand [18F]F-fluciclovine PET/CT use in the context of other imaging modalities in this disease.

CLINICAL TRIAL REGISTRATION

NCT04018053 Registered 2/26/2020.

Abdominal Inflammatory Lesions Mimicking Malignancy: Imaging Pitfalls and Clues

Abdominal inflammatory lesions may closely mimic malignancies on imaging, leading to diagnostic uncertainty and potentially unnecessary interventions. This pictorial review presents a series of cases involving diverse inflammatory conditions-including autoimmune pancreatitis, xanthogranulomatous cholecystitis, diverticulitis, peritoneal tuberculosis, and others-that radiologically resembled neoplastic processes. Key imaging findings, such as mass-forming patterns, enhancement characteristics, and diffusion restriction, are discussed alongside clinical and laboratory correlations. Recognizing these mimickers is essential, as accurate diagnosis often depends on a multidisciplinary approach that integrates imaging expertise with clinical context, ultimately improving patient care and avoiding misdiagnosis.

VI-RADS followed by Photodynamic Transurethral Resection of Non-Muscle-Invasive Bladder Cancer vs White-Light Conventional and Second-resection: the 'CUT-less' Randomised Trial Protocol

BACKGROUND

A second transurethral resection of bladder tumour (Re-TURBT) is recommended by European Association of Urology (EAU) Guidelines on non-muscle-invasive bladder cancers (NMIBCs) due to the risk of understaging and/or persistent disease following the primary resection. However, in many cases this may be unnecessary, potentially harmful, and significantly expensive constituting overtreatment. The CUT-less trial aims to combine the preoperative staging accuracy of Vesical Imaging-Reporting and Data System (VI-RADS) and the intraoperative enhanced ability of photodynamic diagnosis (PDD) to overcome the primary TURBT pitfalls thus potentially re-defining criteria for Re-TURBT indications.

STUDY DESIGN

Single-centre, non-inferiority, phase IV, open-label, randomised controlled trial with 1:1 ratio.

ENDPOINTS

The primary endpoint is short-term BC recurrence between the study arms to assess whether patients preoperatively categorised as VI-RADS Score 1 and/or Score 2 (i.e., very-low and low likelihood of MIBC) could safely avoid Re-TURBT by undergoing primary PDD-TURBT. Secondary endpoints include mid- and long-term BC recurrences and progression (i-ii). Also, health-related quality of life (HRQoL) outcomes (iii) and health-economic cost-benefit analysis (iv) will be performed.

PATIENTS AND METHODS

All patients will undergo preoperative Multiparametric Magnetic Resonance Imaging of the bladder with VI-RADS score determination. A total of 327 patients with intermediate-/high-risk NMIBCs, candidate for Re-TURBT according to EAU Guidelines, will be enrolled over a 3-year period. Participants will be randomised (1:1 ratio) to either standard of care (SoC), comprising primary white-light (WL) TURBT followed by second WL Re-TURBT; or the Experimental arm, comprising primary PDD-TURBT and omitting Re-TURBT. Both groups will receive adjuvant intravesical therapy and surveillance according to risk-adjusted schedules. Measure of the primary outcome will be the relative proportion of BC recurrences between the SoC and Experimental arms within 4.5 months (i.e., any 'early' recurrence detected at first follow-up cystoscopy). Secondary outcomes measures will be the relative proportion of late BC recurrences and/or BC progression detected after 4.5 months follow-up. Additionally, we will compute the HRQoL variation from NMIBC questionnaires modelled over a patient lifetime horizon and the health-economic analyses including a short-term cost-benefit assessment of incremental costs per Re-TURBT avoided and a longer-term cost-utility per quality-adjusted life year gained using 2-year clinical outcomes to drive a lifetime model across the two arms of treatment.

TRIAL REGISTRATION

ClinicalTrial.gov identifier (ID): NCT05962541; European Union Drug Regulating Authorities Clinical Trials Database (EudraCT) ID: 2023-507307-64-00.

VI steps to achieve VI-RADS assessment

Bladder cancer is categorized into nonmuscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC), distinguished by the presence of detrusor muscle invasion. Urothelial cell carcinoma is the most common subtype of bladder cancer. Transurethral resection of bladder tumor (TURBT) is the standard approach for staging and managing NMIBC, while radical cystectomy remains the cornerstone treatment for MIBC. Multiparametric magnetic resonance imaging (mpMRI), comprising morphological imaging sequences (high-resolution T2-weighted images) and functional imaging sequences (dynamic contrast-enhanced images and diffusion-weighted images), serves as an ideal modality. It provides high-contrast resolution for visualizing bladder wall layers, thereby enabling proper and timely staging of bladder cancer. MRI can guide sampling resection and identify patients understaged after primary TURBT, facilitating appropriate surgical restaging. In 2018, the Vesical Imaging Reporting and Data System (VI-RADS), implementing a 5-point scale, was developed to standardize MRI protocols and reporting criteria-including tumor location, size, morphology, and invasiveness. The aim of this article is to navigate through all the steps to achieve VI-RADS assessment and to discuss practical pearls and pitfalls in the use of mpMRI. This approach can aid in pre-TURBT prediction of muscle invasion, representing an important asset in bladder cancer staging.

Urologic Imaging of the Bladder: Cancers and Mimics

Bladder cancer (BC) represents a significant global health challenge with notable incidence and mortality rates. Despite treatment advancements, its management remains complex, requiring a multidisciplinary approach. Imaging techniques play a pivotal role in diagnosis, staging, and treatment planning by aiding lesion localization, differentiation, and assessment of tumor extent. Primary modalities like computed tomography and MRI offer detailed anatomic insights. Imaging provides valuable insights into tumor biology, vascular patterns, and molecular profiles, enabling personalized medicine strategies to optimize therapeutic efficacy and minimize adverse effects, crucial for improving BC management and prognosis.

Computed tomography-based nomogram for estimating progression-free survival probability in bladder cancer patients undergoing partial cystectomy

PURPOSE

To establish a prognostic model to estimate progression-free survival (PFS) probability in bladder cancer (BCa) patients undergoing partial cystectomy.

MATERIAL AND METHODS

Consecutive patients who underwent partial cystectomy between August 2012 and April 2021 were enrolled. The primary endpoint was PFS during the follow-up. The following features were assessed: tumor location, amount, size, tortuous blood vessels around or within the lesions, perivesical fat stranding, stalk, computed tomography (CT) enhancement, calcification, cystic degeneration, CT reported lymph nodes status, and presence of hydronephrosis. Univariate Cox regression and LASSO regression, followed by backward stepwise multivariable Cox, were used to construct the nomogram.

RESULTS

A total of 106 patients were enrolled. Gender, histology, tortuous blood vessels, and perivesical fat stranding were used to fit the nomogram. The overall Harrell's concordance index (C-index) was 0.752. The area under the receiver operator characteristic curves (AUC) at 1-year, 2-year and 3-year were 0.733, 0.789 and 0.833, respectively. The calibration curves showed remarkable consistency.

CONCLUSION

A nomogram model constructed based on the CT features and clinical risk factors is potentially feasible for predicting the PFS within 3 years after PC for BCa, which can assist in the choice of treatment and follow-up scheduling.

ACR Appropriateness Criteria® Pretreatment Staging of Urothelial Cancer: 2024 Update

Urothelial cancer is the second most common cancer, and cause of cancer death, related to the genitourinary tract. The goals of imaging for pretreatment staging of urothelial cancer are to evaluate for both local and distant spread of the cancer and assessing for synchronous sites of urothelial cancer in the upper tracts and bladder. For pretreatment staging of urothelial carcinoma, patients can be stratified into one of three groups: 1) nonmuscle invasive bladder cancer; 2) muscle invasive bladder cancer; and 3) upper urinary tract urothelial carcinoma. This document is a review of the current literature for urothelial cancer and resulting recommendations for pretreatment staging imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Occult urothelial carcinoma with mediastinal metastasis: A case report

Occult urothelial carcinoma (UC), particularly with mediastinal metastases, is an uncommon clinical occurrence. The present study describes the unusual case of a 70-year-old male patient who developed mediastinal metastases from an occult UC. Histological evaluations and immunohistochemical features of the mediastinal tumor were indicative of UC; however, extensive imaging failed to identify the primary urological lesion. The findings suggest that mediastinal metastases from UCs, despite their rarity, should be considered in cases where patients with mediastinal tumors exhibit chest-related symptoms. Prompt pathological examinations are crucial for ascertaining the nature and origin of the tumor. Moreover, individualized treatment should be performed in strict accordance with the established oncology guidelines.

Practical Guide to VI-RADS: MRI Protocols, Lesion Characterization, and Pitfalls

Urothelial carcinoma is the most common type of bladder cancer (BC), accounting for approximately 90% of all cases. Evaluating the depth of tumor invasion in the bladder wall (tumor staging) is essential for determining the treatment and prognosis in patients with BC. Neoadjuvant therapy followed by radical cystectomy is the most common treatment of localized muscle-invasive BC (MIBC). Therefore, it is vital to differentiate non-MIBC from MIBC. Transurethral resection of bladder tumor (TURBT) is the reference standard to determine the extent of tumor invasion into the bladder wall through tissue sampling. However, this diagnostic and therapeutic method may not adequately sample the muscularis propria, leading to a higher risk of residual disease, early recurrence, and tumor understaging in approximately 50% of patients during the initial TURBT. Multiparametric MRI can overcome some of the limitations of TURBT when evaluating BC, particularly regarding tumor staging. In this context, the Vesical Imaging Reporting and Data System (VI-RADS) classification was developed to establish standards for bladder multiparametric MRI and interpretation. It uses a 5-point scale to assess the likelihood of detrusor muscle invasion. T2-weighted MR images are particularly useful as an initial guide, especially for categories 1-3, while the presence of muscular invasion is determined with diffusion-weighted and dynamic contrast-enhanced sequences. Diffusion-weighted imaging takes precedence as the dominant method when optimal image quality is achieved. The presence of a stalk or a thickened inner layer and no evidence of interruption of the signal intensity of the muscular layer are central for predicting a low likelihood of muscle invasion. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Hoegger in this issue.

Computed tomography-based prediction model for identifying patients with high probability of non-muscle-invasive bladder cancer

PURPOSE

To investigate computed tomography (CT)-based prediction model for identifying patients with high probability of non-muscle-invasive bladder cancer (NMIBC).

METHODS

This retrospective study evaluated 147 consecutive patients who underwent contrast-enhanced CT and surgery for bladder cancer. Using corticomedullary-to-portal venous phase images, two independent readers analyzed bladder muscle invasion, tumor stalk, and tumor size, respectively. Three-point scale (i.e., from 0 to 2) was applied for assessing the suspicion degree of muscle invasion or tumor stalk. A multivariate prediction model using the CT parameters for achieving high positive predictive value (PPV) for NMIBC was investigated. The PPVs from raw data or 1000 bootstrap resampling and inter-reader agreement using Gwet's AC1 were analyzed, respectively.

RESULTS

Proportion of patients with NMIBC was 81.0% (119/147). The CT criteria of the prediction model were as follows: (a) muscle invasion score < 2; (b) tumor stalk score > 0; and (c) tumor size < 3 cm. From the raw data, PPV of the model for NMIBC was 92.7% (51/55; 95% confidence interval [CI] 82.4-98.0) in reader 1 and 93.3% (42/45; 95% CI 81.7-98.6) in reader 2. From the bootstrap data, PPV was 92.8% (95% CI 85.2-98.3) in reader 1 and 93.4% (95% CI 84.9-99.9) in reader 2. The model's AC1 was 0.753 (95% CI 0.647-0.859).

CONCLUSION

The current CT-derived prediction model demonstrated high PPV for identifying patients with NMIBC. Depending on CT findings, approximately 30% of patients with bladder cancer may have a low need for additional MRI for interpreting vesical imaging-reporting and data system.

MRI/RNA-Seq-Based Radiogenomics and Artificial Intelligence for More Accurate Staging of Muscle-Invasive Bladder Cancer

Accurate staging of bladder cancer assists in identifying optimal treatment (e.g., transurethral resection vs. radical cystectomy vs. bladder preservation). However, currently, about one-third of patients are over-staged and one-third are under-staged. There is a pressing need for a more accurate staging modality to evaluate patients with bladder cancer to assist clinical decision-making. We hypothesize that MRI/RNA-seq-based radiogenomics and artificial intelligence can more accurately stage bladder cancer. A total of 40 magnetic resonance imaging (MRI) and matched formalin-fixed paraffin-embedded (FFPE) tissues were available for analysis. Twenty-eight (28) MRI and their matched FFPE tissues were available for training analysis, and 12 matched MRI and FFPE tissues were used for validation. FFPE samples were subjected to bulk RNA-seq, followed by bioinformatics analysis. In the radiomics, several hundred image-based features from bladder tumors in MRI were extracted and analyzed. Overall, the model obtained mean sensitivity, specificity, and accuracy of 94%, 88%, and 92%, respectively, in differentiating intra- vs. extra-bladder cancer. The proposed model demonstrated improvement in the three matrices by 17%, 33%, and 25% and 17%, 16%, and 17% as compared to the genetic- and radiomic-based models alone, respectively. The radiogenomics of bladder cancer provides insight into discriminative features capable of more accurately staging bladder cancer. Additional studies are underway.

Multiparametric MRI in Era of Artificial Intelligence for Bladder Cancer Therapies

This review focuses on the principles, applications, and performance of mpMRI for bladder imaging. Quantitative imaging biomarkers (QIBs) derived from mpMRI are increasingly used in oncological applications, including tumor staging, prognosis, and assessment of treatment response. To standardize mpMRI acquisition and interpretation, an expert panel developed the Vesical Imaging-Reporting and Data System (VI-RADS). Many studies confirm the standardization and high degree of inter-reader agreement to discriminate muscle invasiveness in bladder cancer, supporting VI-RADS implementation in routine clinical practice. The standard MRI sequences for VI-RADS scoring are anatomical imaging, including T2w images, and physiological imaging with diffusion-weighted MRI (DW-MRI) and dynamic contrast-enhanced MRI (DCE-MRI). Physiological QIBs derived from analysis of DW- and DCE-MRI data and radiomic image features extracted from mpMRI images play an important role in bladder cancer. The current development of AI tools for analyzing mpMRI data and their potential impact on bladder imaging are surveyed. AI architectures are often implemented based on convolutional neural networks (CNNs), focusing on narrow/specific tasks. The application of AI can substantially impact bladder imaging clinical workflows; for example, manual tumor segmentation, which demands high time commitment and has inter-reader variability, can be replaced by an autosegmentation tool. The use of mpMRI and AI is projected to drive the field toward the personalized management of bladder cancer patients.

Recent advances in three-dimensional ultrasound virtual cystoscopy in modeling and local staging for urothelial carcinoma with histopathological correlation: a cohort prospective study

Background

Bladder urothelial carcinoma is an alarming urologic malignancy. Complex factors like modelling and local staging can affect treatment strategy. However, local staging, particularly the muscle invasion status, significantly influences decisions regarding treatment strategies. Therefore, this study aims to evaluate the novel advances of three-dimensional (3D) ultrasound (US) imaging to assess local staging in comparison with conventional cystoscopy.

Methods

Forty-three patients with painless haematuria and conventional cystoscopy findings of bladder mass underwent 3D US virtual cystoscopy. All specimens from conventional cystoscopy were processed histologically.

Results

Out of 43 participants, 18 (41.9%) patients proved to have invasive urothelial carcinoma by histopathology. The 3D US had a sensitivity of 97.5% and a specificity of 100%; however conventional cystoscopy was accurate in only 53.5% of the studied cases. Furthermore, in the case of malignant ulcers, mural extension into both the submucosal and the muscle layers was more readily appreciated in multiplanar images.

Conclusion

3D US updates are promising for use in bladder tumour modelling and local staging; however, they can be of value in evaluating mural and extramural tumour extent and have proven accuracy.

Predictive Value of Computed Tomography Following Neoadjuvant Chemotherapy for Muscle Invasive Bladder Cancer

BACKGROUND

Neoadjuvant chemotherapy (NAC) prior to radical cystectomy (RC) remains standard treatment for select patients with muscle-invasive bladder cancer (MIBC). Although computed tomography (CT) is often obtained prior to RC, its ability to predict pathologic response is poorly characterized.

OBJECTIVE

The purpose of this study is to evaluate the predictive value of CT in assessing disease burden after NAC.

METHODS

Patients with MIBC having received NAC prior to RC were identified. Pre- and post-NAC CT scans were reviewed by an abdominal radiologist. The correlation between pathologic complete response (PCR) and radiologic complete response (RCR) was determined as the primary aim. As a secondary aim, the correlation between pathologic partial response (PPR) and radiologic partial response (RPR) was determined. Logistic regression analysis was utilized to determine the predictive value of CT in determining disease burden at RC.

RESULTS

A total of 141 patients were identified for analysis. PCR and PPR was achieved in 34% and 16% of patients, respectively. The positive predictive value of post-NAC CT was 53.5% for PCR and 28.8% for PPR. The negative predictive value of post-NAC CT was 73.5% for PCR and 46.2% for PPR. There was no significant association between RCR and PCR (OR 1.13, p = 0.67). Similarly, there was no meaningful association between RPR and PPR, lymph node involvement, or presence of extravesical disease.

CONCLUSIONS

CT findings correlate poorly with final pathology at RC and should not be used to evaluate local disease burden.

CT of the urinary tract revisited

Computed tomography (CT) of the abdomen is usually appropriate for the initial imaging of many urinary tract diseases, due to its wide availability, fast scanning and acquisition of thin slices and isotropic data, that allow the creation of multiplanar reformatted and three-dimensional reconstructed images of excellent anatomic details. Non-enhanced CT remains the standard imaging modality for assessing renal colic. The technique allows the detection of nearly all types of urinary calculi and the estimation of stone burden. CT is the primary diagnostic tool for the characterization of an indeterminate renal mass, including both cystic and solid tumors. It is also the modality of choice for staging a primary renal tumor. Urolithiasis and urinary tract malignancies represent the main urogenic causes of hematuria. CT urography (CTU) improves the visualization of both the upper and lower urinary tract and is recommended for the investigation of gross hematuria and microscopic hematuria, in patients with predisposing factors for urologic malignancies. CTU is highly accurate in the detection and staging of upper tract urothelial malignancies. CT represents the most commonly used technique for the detection and staging of bladder carcinoma and the diagnostic efficacy of CT staging improves with more advanced disease. Nevertheless, it has limited accuracy in differentiating non-muscle invasive bladder carcinoma from muscle-invasive bladder carcinoma. In this review, clinical indications and the optimal imaging technique for CT of the urinary tract is reviewed. The CT features of common urologic diseases, including ureterolithiasis, renal tumors and urothelial carcinomas are discussed.

Comparison between biparametric and multiparametric MRI in predicting muscle invasion by bladder cancer based on the VI-RADS

This study aimed to compare the diagnostic validity of biparametric magnetic resonance imaging (bpMRI) with that of multiparametric MRI (mpMRI) based on the Vesicle Imaging-Reporting and Data System (VI-RADS) in predicting muscle invasion by bladder cancer (BCa). We retrospectively examined 357 patients with an initial diagnosis of BCa who underwent preoperative MRI; 257 and 100 patients underwent mpMRI and bpMRI, respectively. Two urogenital radiologists evaluated all bpMRI and mpMRI scans using VI-RADS, and the diagnostic validity of VI-RADS for predicting muscle invasion by BCa was analyzed based on histopathology of the first and/or second transurethral resection of bladder tumors and radical cystectomy. Receiver operating characteristic (ROC) curves were plotted with the calculation of area under the curves (AUCs), and the level of significance was P < 0.05. Both groups showed optimal performance with a VI-RADS score ≥ 3. BpMRI showed comparable diagnostic performance to mpMRI (reader 1: AUC, 0.903 [0.827-0.954] vs. 0.935 [0.884-0.968], p = 0.510; and reader 2: AUC, 0.901 [0.814-0.945] vs. 0.915 [0.874-0.946]; p = 0.655). The inter-reader agreement between both readers was excellent (Cohen's kappa value = 0.942 and 0.905 for bpMRI and mpMRI, respectively). This comparative study suggests that bpMRI has comparable diagnostic performance to mpMRI and may be an alternative option to predict muscle invasion by BCa.

Role of multiparametric magnetic resonance imaging in the diagnosis and staging of urinary bladder cancer

Objectives

To assess the role of multiparametric magnetic resonance imaging (mp-MRI) in the diagnosis and staging of urinary bladder cancer (BC).

Materials and methods

Fifty patients diagnosed with bladder masses underwent mp-MRI study. The results of 3 image sets were analyzed and compared with the histopathological results as a reference standard: T2-weighted image (T2WI) plus dynamic contrast-enhanced (DCE), T2WI plus diffusion-weighted images (DWI), and mp-MRI, including T2WI plus DWI and DCE. The diagnostic accuracy of mp-MRI was evaluated using receiver operating characteristic curve analysis.

Results

The accuracy of T2WI plus DCE for detecting muscle invasion of BC was 79.5% with a fair agreement with histopathological examination (κ = 0.59); this percentage increased up to 88.6% using T2WI plus DWI, with good agreement with histopathological examination (κ = 0.74), whereas mp-MRI had the highest overall accuracy (95.4%) and excellent agreement with histopathological data (κ = 0.83). Multiparametric MRI can differentiate between low- and high-grade bladder tumors with a high sensitivity and specificity of 93.3% and 98.3%, respectively.

Conclusions

Multiparametric MRI is an acceptable method for the preoperative detection and accurate staging of BC, with reasonable accuracy in differentiating between low- and high-grade BC.

Advances in Transversal Topics Applicable to the Care of Bladder Cancer Patients in the Real-World Setting

Recommendations regarding transversal topics applicable to bladder cancer patients independent of tumor grade and stage were established by members of the Spanish Oncology Genitourinary Multidisciplinary Working Group (SOGUG). Liquid biopsy in urine and blood samples is useful in the surveillance of non-muscle-invasive and muscle-invasive bladder cancer, respectively. Multiparametric MRI is an accurate, faster and non-invasive staging method overcoming the understaging risk of other procedures. The combination of FDG-PET/MRI could improve diagnostic reliability, but definite criteria for imaging interpretation are still unclear. Hospital oncology pharmacists as members of tumor committees improve the safety of drug use. Additionally, safety recommendations during BCG preparation should be strictly followed. The initial evaluation of patients with bladder cancer should include a multidimensional geriatric assessment. Orthotopic neobladder reconstruction should be offered to motivated patients with full information of self-care requirements. Bladder-sparing protocols, including chemoradiation therapy and immune checkpoints inhibitors (ICIs), should be implemented in centers with well-coordinated multidisciplinary teams and offered to selected patients. The optimal strategy of treatment with ICIs should be defined from the initial diagnostic phase with indications based on scientific evidence. Centralized protocols combined with the experience of professional groups are needed for the integral care of bladder cancer patients.

Prediction of Metastatic Patterns in Bladder Cancer: Spatiotemporal Progression and Development of a Novel, Web-based Platform for Clinical Utility

Background

Bladder cancer (BCa), the sixth commonest cancer in the USA, is highly lethal when metastatic. Spatial and temporal patterns of patient-specific metastatic spread are deemed random and unpredictable. Whether BCa metastatic patterns can be quantified and predicted more accurately is unknown.

Objective

To develop a web-based calculator for forecasting metastatic progression in individual BCa patients.

Design setting and participants

We used a prospectively collected longitudinal dataset of 3503 BCa patients who underwent a radical cystectomy following diagnosis and were enrolled continuously. We subdivided patients by their pathologic subgroup stages of organ confined (OC), extravesical (EV), and node positive (N+). We illustrated metastatic pathway progression using color-coded, circular, tree ring diagrams. We created a dynamical, data-visualization, web-based platform that displays temporal, spatial, and Markov modeling figures with predictive capability.

Outcome measurements and statistical analysis

Patients underwent history and physical examination, serum studies, and liver function tests. Surveillance follow-up included computed tomography scans, chest x-rays, and radiographic evaluation of the reservoir and upper tracts, with bone scans performed only if clinically indicated. Outcomes were measured by time to clinical recurrence and overall or progression-free survival.

Results and limitations

Metastases developed in 29% of patients (n = 812; median follow-up 15.3 yr), with 5-yr overall survival of 20.2%, compared with 78.6% in those without metastases (n = 1983; median follow-up 10.9 yr). The three commonest sites of spread at the time of first progression were bone (n = 214; 26.4%), pelvis (n = 194; 23.9%), and lung (n = 194; 23.9%). The order and frequency of these sites vary when divided by pathologic subgroup stages of OC (lung [n = 65; 25.1%], urethra [n = 45; 17.4%], and bone [n = 29; 11.2%]), EV (pelvis [n = 63; 33.0%], bone [n = 45; 23.6%], and lung [n = 29; 15.2%]), and N+ (bone [n = 111; 30.7%], retroperitoneum [n = 70; 19.3%], and pelvis [n = 60; 16.6%]). Markov chain modeling indicated a higher probability of spread from bladder to bone (15.5%), pelvis (14.7%), and lung (14.2%).

Conclusions

Our web-based calculator allows real-time analyses in the clinic based on individual patient-specific demographic and cancer data elements. For contrasting subgroups, the models indicated differences in Markov transition probabilities. Spatiotemporal patterns of BCa metastasis and sites of spread indicated underlying organotropic mechanisms in the prediction of response. This recognition opens the possibility of organ site-specific therapeutic targeting in the oligometastatic BCa setting. In the precision medicine era, visualization of complex, time-resolved clinical data will enhance management of postoperative metastatic BCa patients.

Patient summary

We developed a web-based calculator to forecast metastatic progression for individual bladder cancer (BCa) patients, based on the clinical and demographic information obtained at diagnosis. This can help in predicting disease status and survival, and improving management in postoperative metastatic BCa patients.

Take  Home Message

Future pathways of metastatic progression for individual bladder cancer patients can be determined based on currently available clinical and demographic information obtained at diagnosis. In focused subgroups of patients, these metastatic spread patterns can also portend disease status and survival.

Detecting Muscle Invasion of Bladder Cancer Using a Proposed Magnetic Resonance Imaging Strategy

BACKGROUND

Accurate evaluation of the invasion depth of tumors with a Vesical Imaging-Reporting and Data System (VI-RADS) score of 3 is difficult.

PURPOSE

To evaluate the diagnostic performance of a new magnetic resonance imaging (MRI) strategy based on the integration of the VI-RADS and tumor contact length (TCL) for the diagnosis of muscle-invasive bladder cancer (MIBC).

STUDY TYPE

Single center, retrospective.

SUBJECTS

A group of 179 patients with a mean age of 67 years (range, 24.0-96.0) underwent multiparametric MRI (mpMRI) before surgery, including 147 (82.1%) males and 32 (17.9%) females. Twenty-four (13.4%), 90 (50.3%), 43 (24.0%), 15 (8.4%), and 7 (3.9%) cases were Ta, T1, T2, T3, and T4, respectively.

FIELD STRENGTH/SEQUENCE

A 1.5 T and 3.0 T, T2-weighted turbo spin-echo (TSE), single-shot echo-planar (SS-EPI), diffusion-weighted imaging (DWI), and T1-weighted volumetric interpolated breath-hold examination (T1-VIBE).

ASSESSMENT

Three radiologists independently graded the VI-RADS score and measured the TCL on index lesion images. A proposed MRI strategy called VI-RADS_TCL was introduced by modifying the VI-RADS score, which was downgraded to VI-RADS 3F (equal to a VI-RADS score of 2) if VI-RADS = 3 and TCL < 3 cm.

STATISTICAL TESTS

Intraclass correlation coefficients (ICCs), Mann-Whitney U test, chi-square tests, receiver operating characteristic (ROC) curves, and 2 × 2 contingency tables were applied.

RESULTS

Inter-reader agreement values were 0.941 (95% CI, 0.924-0.955) and 0.934 (95% CI, 0.916-0.948) for the TCL and VI-RADS score. The TCL was significantly increased in the MIBC group (6.40-6.85 cm) compared with the NMIBC group (1.98-2.45 cm) (P < 0.05). The specificity and positive predictive values (PPV) of VI-RADS_TCL were 82.46%-87.72% and 90.91%-91.59%, which were significantly greater than VI-RADS score (P < 0.05). Additionally, 52.17%-55.88% NMIBC lesions with VI-RADS 3 were downgraded to 3F by using VI-RADS_TCL.

DATA CONCLUSION

The proposed MRI strategy could reduce the false-positive rate of lesions with a VI-RADS score of 3 while retaining sensitivity.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: 2.

Vesical Imaging-Reporting and Data System (VI-RADS®): Initial experience in the classification of muscle-invasive bladder cancer

OBJECTIVE

to analyze the diagnostic accuracy of the VI-RADS® system in the differentiation of non-muscle-invasive bladder tumors (NMIBT from muscle-invasive bladder tumors (MIBT in suspicious cystoscopic findings without prior transurethral resection (TUR evaluated by radiologists with no prior experience in its use.

MATERIAL AND METHODS

retrospective study carried out with 18 patients with suspicious lesions in cystoscopy. All of them underwent MRI of the bladder. Two radiologists with no prior experience in the use of the VI-RADS® system evaluated the results. All patients underwent TUR of the suspicious lesions after MRI. The sensitivity and specificity of the system were analyzed for VI-RADS® values ≥ 3 or VI-RADS® ≥ 4, as well as the Cohen's kappa coefficient between both radiologists.

RESULTS

the mean values of sensitivity and specificity of both radiologists considering both the VI-RADS® ≥ 3 or VI-RADS® ≥ 4 values were 91.7% and 87.5%, respectively. The kappa coefficient considering the VI-RADS® ≥ 3 as positive, was 0.551 (P<.05), while considering the VI-RADS® ≥ 4 as positive, it was 0.571 (P<.05).

CONCLUSION

The VI--RADS® system presents excellent sensitivity (91.7% and specificity (87.5% values in the classification of MIBT performed by radiologists with no prior experience in its use, with a moderate interobserver agreement.

Primary squamous cell carcinoma of the urinary bladder presenting as an inguinal mass

This report involves a rare case of a 74-year-old man who presented with a progressively increasing swelling in the right groin, which represented a squamous cell bladder carcinoma herniating into the right inguinal canal. The manuscript discusses the role of multimodality imaging in bladder carcinoma presenting as an inguinoscrotal hernia. The patient subsequently underwent treatment with a chemotherapy regimen consisting of 5-fluorouracil and mitomycin, which was extrapolated from squamous cell carcinoma of the anal canal, and responded well.

Imaging and Management of Bladder Cancer

METHODS

Keyword searches of Medline, PubMed, and the Cochrane Library for manuscripts published in English, and searches of references cited in selected articles to identify additional relevant papers. Abstracts sponsored by various societies including the American Urological Association (AUA), European Association of Urology (EAU), and European Society for Medical Oncology (ESMO) were also searched.

BACKGROUND

Bladder cancer is the sixth most common cancer in the United States, and one of the most expensive in terms of cancer care. The overwhelming majority are urothelial carcinomas, more often non-muscle invasive rather than muscle-invasive. Bladder cancer is usually diagnosed after work up for hematuria. While the workup for gross hematuria remains CT urography and cystoscopy, the workup for microscopic hematuria was recently updated in 2020 by the American Urologic Association with a more risk-based approach. Bladder cancer is confirmed and staged by transurethral resection of bladder tumor. One of the main goals in staging is determining the presence or absence of muscle invasion by tumor which has wide implications in regards to management and prognosis. CT urography is the main imaging technique in the workup of bladder cancer. There is growing interest in advanced imaging techniques such as multiparametric MRI for local staging, as well as standardized imaging and reporting system with the recently created Vesicle Imaging Reporting and Data System (VI-RADS). Therapies for bladder cancer are rapidly evolving with immune checkpoint inhibitors, particularly programmed death ligand 1 (PD-L1) and programmed cell death protein 1 (PD-1) inhibitors, as well as another class of immunotherapy called an antibody-drug conjugate which consists of a cytotoxic drug conjugated to monoclonal antibodies against a specific target.

CONCLUSION

Bladder cancer is a complex disease, and its management is evolving. Advances in therapy, understanding of the disease, and advanced imaging have ushered in a period of rapid change in the care of bladder cancer patients.

Imaging of Bladder Cancer: Standard Applications and Future Trends

The evolution in imaging has had an increasing role in the diagnosis, staging and follow up of bladder cancer. Conventional cystoscopy is crucial in the diagnosis of bladder cancer. However, a cystoscopic procedure cannot always depict carcinoma in situ (CIS) or differentiate benign from malignant tumors prior to biopsy. This review will discuss the standard application, novel imaging modalities and their additive role in patients with bladder cancer. Staging can be performed with CT, but distinguishing between T1 and T2 BCa (bladder cancer) cannot be assessed. MRI can distinguish muscle-invasive from non-muscle-invasive tumors with accurate local staging. Vesical Imaging-Reporting and Data System (VI-RADS) score is a new diagnostic modality used for the prediction of tumor aggressiveness and therapeutic response. Bone scintigraphy is recommended in patients with muscle-invasive BCa with suspected bony metastases. CT shows low sensitivity for nodal staging; however, PET (Positron Emission Tomography)/CT is superior and highly recommended for restaging and determining therapeutic effect. PET/MRI is a new imaging technique in bladder cancer imaging and its role is promising. Texture analysis has shown significant steps in discriminating low-grade from high-grade bladder cancer. Radiomics could be a reliable method for quantitative assessment of the muscle invasion of bladder cancer.

Estadificación clínica como factor pronóstico en cáncer de vejiga músculo-invasor

El cáncer de vejiga músculo invasor (CV-MI), requiere de una adecuada estadificación clínica y patológica, ya que eso determina las estrategias terapéuticas y el pronóstico de la enfermedad, caracterizada por una alta morbimortalidad. Este articulo tiene como objetivo realizar una revisión de la literatura sobre la exactitud diagnóstica de las técnicas de imagen disponibles para la estadificación clínica de los pacientes con CV-MI y cómo se debería realizar el seguimiento radiológico en los pacientes llevados a cirugía. Para eso se realizó una búsqueda en la base de datos Pubmed de artículos en inglés y en español, se incluyeron artículos de revisión, metanálisis, guías clínicas, estudios retrospectivos y prospectivos de pronóstico y diagnóstico desde el año 1988 hasta el año 2020.

Role of magnetic resonance imaging in tumor staging and follow-up for bladder cancer

Urothelial carcinoma of the bladder is a common urologic malignancy. Complex factors, such as local stage, tumor grade, biologic potential, and various conditions, can affect the treatment strategy for bladder cancer. However, the local stage-in particular, the presence or absence of muscle invasion-significantly influences decisions regarding treatment strategy. The role of cystoscopy for screening, diagnosis, and transurethral resection cannot be overlooked. The importance of local staging with magnetic resonance imaging is increasing; magnetic resonance imaging of the bladder is considered a useful staging modality. Moreover, a radiologic reporting system for evaluating and scoring muscle invasion of bladder cancer was recently released. This system is based on multiparametric magnetic resonance imaging and is also expected to be feasible for post-treatment follow-up of bladder cancer. In this review, we discuss the role of magnetic resonance imaging in the local staging of urothelial carcinoma of the urinary bladder and post-treatment imaging. In addition, several technical aspects for obtaining appropriate quality magnetic resonance images of the bladder will be discussed.

Multiparametric magnetic resonance imaging for bladder cancer: a comprehensive systematic review of the Vesical Imaging-Reporting and Data System (VI-RADS) performance and potential clinical applications

BACKGROUND

The Vesical Imaging-Reporting and Data System (VI-RADS) score is a novel standardized approach to image and report bladder cancer (BC) with multiparametric MRI (mpMRI).

OBJECTIVES

To describe and evaluate the performance of the VI-RADS score using mpMRI and assess its potential clinical applications and limitations.

METHODS

A systematic review was conducted using the MEDLINE and EMBASE electronic bibliographic databases between June 2020 and December 2020. All reports deemed relevant to describe the VI-RADS score and assess its performance and applications were retrieved. Results presentation stands as narrative, purely descriptive synthesis based on aggregate studies data.

RESULTS

A total of 20 relevant studies were retrieved: three meta-analyses, five prospective studies, and twelve retrospective studies. The retrospective studies covered 1676 patients, while the prospective studies included a total number of 468 patients. Pooled sensitivity, specificity to differentiate muscle-invasive from non-muscle-invasive bladder cancer, ranged from 74.1% to 97.3%, and 77% to 100%, respectively. The chosen VI-RADS score thresholds for this discrimination varied across studies. The interreader agreement ranged from 0.73 to 0.95. Currently, the potential clinical applications of VI-RADS consist of initial BC risk stratification, assessment of neoadjuvant therapies response, and bladder sparing approaches, although further validation is required.

CONCLUSIONS

The VI-RADS score helps to discriminate muscle invasive from non-muscle invasive BC with good performance and reproducibility. A simple algorithm based on four basic questions may enhance its popularization. Further studies are required to validate the clinical applications.

Urothelial Carcinoma of the Bladder: Radiologic Perspective

방광암은 비교적 흔히 진단되는 암이며 재발이 흔해 영상의학적 검사에서 흔히 만날 수 있다. 방광암의 정확한 진단과 병기 평가는 어떤 치료를 할 것인지를 정하고 예후를 평가하는데 큰 영향을 미친다. 방광암의 임상적 병기 평가는 요도경유방광종양절제술로 진단과 치료를 겸해서 이루어졌지만, 저평가되는 경우가 흔히 있다. 수술 전 방광암의 위치, 크기, 근육층 침범 유무, 림프절전이, 원격전이, 상부요로 암 유무 등을 영상의학적 검사에서 정확히 진단 및 평가할 수 있다면 더욱 적절히 처치 및 관리를 할 수 있다. 이런 정확한 진단을 위해서는 영상을 판독하는 영상의학과 의사는 먼저 방광암의 임상적인 특징을 잘 알고 있어야 한다. 그리고 영상 검사들의 종류와 특징, 한계를 알고 있어야 한다. 최근 자기공명영상의 발달로 방광 영상의 질 및 방광암의 진단과 평가가 향상되었다. 그리고 방광 이미징 보고 및 데이터시스템이 발표되어 객관적으로 방광암의 근육층 침범 가능성을 평가할 수 있게 되었다. 방광암 치료 종류를 알고 그에 따른 치료 후 변화에는 무엇이 있는지 어떻게 평가하는지도 알아야 하겠다. 이 종설에서는 방광 요로상피세포암의 특징과 다양한 영상의학 검사와 소견에 대해서 알아보고자 한다.

VI-RADS for Bladder Cancer: Current Applications and Future Developments

Bladder cancer (BCa) is among the ten most frequent cancers globally. It is the tumor with the highest lifetime treatment-associated costs, and among the tumors with the heaviest impacts on postoperative quality of life. The purpose of this article is to review the current applications and future perspectives of the Vesical Imaging Reporting and Data System (VI-RADS). VI-RADS is a newly developed scoring system aimed at standardization of MRI acquisition, interpretation, and reporting for BCa. An insight will be given on the BCa natural history, current MRI applications for local BCa staging with assessment of muscle invasiveness, and clinical implications of the score for disease management. Future applications include risk stratification of nonmuscle invasive BCa, surveillance, and prediction and monitoring of therapy response. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.

The Role of Imaging in Bladder Cancer Diagnosis and Staging

Bladder cancer (BC) is the most common cancer of the urinary tract in the United States. Imaging plays a significant role in the management of patients with BC, including the locoregional staging and evaluation for distant metastatic disease, which cannot be assessed at the time of cystoscopy and biopsy/resection. We aim to review the current role of cross-sectional and molecular imaging modalities for the staging and restaging of BC and the potential advantages and limitations of each imaging modality. CT is the most widely available and frequently utilized imaging modality for BC and demonstrates good performance for the detection of nodal and visceral metastatic disease. MRI offers potential value for the locoregional staging and evaluation of muscular invasion of BC, which is critically important for prognostication and treatment decision-making. FDG-PET/MRI is a novel hybrid imaging modality combining the advantages of both MRI and FDG-PET/CT in a single-setting comprehensive staging examination and may represent the future of BC imaging evaluation.

[Bladder cancer local staging about muscle invasion: 3.0T MRI performance following transurethral resection]

OBJECTIVE

To evaluate the performance of 3.0T magnetic resonance imaging examination (MRI) for the local detecting of muscle invasive bladder cancer following transurethral resection of bladder tumor (TURBT).

METHODS

Retrospective study identified 55 patients with pathology-proven bladder cancer who underwent transurethral resection of bladder tumor followed by 3.0T magnetic resonance imaging between September 2012 and April 2019 in our hospital. Two radiologists reviewed pelvic magnetic resonance imaging together and judged muscle invasive bladder cancer. Sensitivity, specificity and accuracy were calculated for the presence of muscle invasion by T2 weighted imaging (T2WI) only, diffusion-weighted imaging (DWI) only and T2WI+DWI compared with the findings at radical cystectomy as the reference standard.

RESULTS

Of the 55 patients with pathological results from radical cystectomy, 3.64% (2/55) had no residual disease; 29.09% (16/55) were non-muscle invasive bladder cancer on pathology, including 13 cases in T1 and 3 cases in Ta; 34.55% (19/55) were in stage T2 depending on pathology, 25.45% (14/55) in T3, and 7.27% (4/55) in T4. The average age was 60.76 years, ranging from 42 to 82 years. There were 48 males and 7 females in our study. Before pelvic MRI examination, all the patients received transurethral resection of bladder tumor, including 16 cases taking the operation in our hospital and 39 cases in other hospitals. The interval between the pelvic MRI examination and transurethral resection of bladder tumor was more than 2 weeks in all the patients. They all underwent radical cystectomy within 1 month after the pelvic MRI examination, and no patient underwent radiotherapy or chemotherapy in our study during the interval between the MRI examination and radical cystectomy. T2WI only, DWI only, and T2WI+DWI of 3.0T magnetic resonance imaging for readers were with sensitivity: 94.59%, 83.78%, 91.89%; with specificity: 66.67%, 77.78%, 72.22% and with accuracy: 85.45%, 81.82%, 85.45%, respectively.

CONCLUSION

3.0T MRI may have a role in diagnosing muscle invasive bladder cancer following TURBT. T2WI has the advantage of detecting the location of bladder tumor, and DWI has the advantage of differentiating between the benign and malignant lesion. 3.0T MRI T2WI+DWI has a good utility in the detection of muscle invasive bladder cancer following TURBT with satisfied accuracy.

French ccAFU guidelines – Update 2018–2020: Bladder cancer

Objective

To propose updated French guidelines for non-muscle invasive (NMIBC) and muscle-invasive (MIBC) bladder cancers.

Methods

A Medline search was achieved between 2015 and 2018, as regards diagnosis, options of treatment and follow-up of bladder cancer, to evaluate different references with levels of evidence.

Results

Diagnosis of NMIBC (Ta, T1, CIS) is based on a complete deep resection of the tumor. The use of fluorescence and a second-look indication are essential to improve initial diagnosis. Risks of both recurrence and progression can be estimated using the EORTC score. A stratification of patients into low, intermediate and high risk groups is pivotal for recommending adjuvant treatment: instillation of chemotherapy (immediate post-operative, standard schedule) or intravesical BCG (standard schedule and maintenance). Cystectomy is recommended in BCG-refractory patients. Extension evaluation of MIBC is based on contrast-enhanced pelvic-abdominal and thoracic CT-scan. Multiparametric MRI can be an alternative. Cystectomy associated with extended lymph nodes dissection is considered the gold standard for non-metastatic MIBC. It should be preceded by cisplatin-based neoadjuvant chemotherapy in eligible patients. An orthotopic bladder substitution should be proposed to both male and female patients with no contraindication and in cases of negative frozen urethral samples; otherwise transileal ureterostomy is recommended as urinary diversion. All patients should be included in an Early Recovery After Surgery (ERAS) protocol. For metastatic MIBC, first-line chemotherapy using platin is recommended (GC or MVAC), when performans status (PS < 1) and renal function (creatinine clearance > 60 mL/min) allow it (only in 50 % of cases). In second line treatment, immunotherapy with pembrolizumab demonstrated a significant improvement in overall survival.

Conclusion

These updated French guidelines will contribute to increase the level of urological care for the diagnosis and treatment for NMIBC and MIBC.

Overview of VI-RADS in Bladder Cancer

OBJECTIVE. The purpose of this article is to review the natural history and management of bladder cancer, with insight into MRI applications for the assessment of muscle invasiveness of bladder cancer using the newly developed Vesical Imaging Reporting and Data System (VI-RADS) score. CONCLUSION. Multiparametric MRI and the VI-RADS score have been consistently validated across several different institutions as appropriate tools for local staging of bladder cancer and have been proven to contribute to the diagnostic workup and management of urinary bladder cancer.

MRI of Bladder Cancer: Local and Nodal Staging

Accurate staging of bladder cancer (BC) is critical, with local tumor staging directly influencing management decisions and affecting prognosis. However, clinical staging based on clinical examination, including cystoscopy and transurethral resection of bladder tumor (TURBT), often understages patients compared to final pathology at radical cystectomy and lymph node (LN) dissection, mainly due to underestimation of the depth of local invasion and the presence of LN metastasis. MRI has now become established as the modality of choice for the local staging of BC and can be additionally utilized for the assessment of regional LN involvement and tumor spread to the pelvic bones and upper urinary tract (UUT). The recent development of the Vesical Imaging-Reporting and Data System (VI-RADS) recommendations has led to further improvements in bladder MRI, enabling standardization of image acquisition and reporting. Multiparametric magnetic resonance imaging (mpMRI) incorporating morphological and functional imaging has been proven to further improve the accuracy of primary and recurrent tumor detection and local staging, and has shown promise in predicting tumor aggressiveness and monitoring response to therapy. These sequences can also be utilized to perform radiomics, which has shown encouraging initial results in predicting BC grade and local stage. In this article, the current state of evidence supporting MRI in local, regional, and distant staging in patients with BC is reviewed. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2 J. Magn. Reson. Imaging 2020;52:649-667.

Urothelial phase CT for assessment of pathologic complete response after neoadjuvant chemotherapy in muscle-invasive bladder cancer

PURPOSE

To investigate the diagnostic performance of urothelial phase (UP) CT and identify the appropriate imaging criteria for assessment of pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) in patients with bladder cancer.

METHOD

Seventy-three patients who underwent NAC and subsequent radical or partial cystectomy between January 2017 and July 2019 were retrospectively analyzed. UP CT findings after NAC were divided into five grades as follows: grade 1, no wall thickening or inner-layer enhancement; grade 2, thin inner-layer enhancement without wall thickening; grade 3, inner-layer enhancement with low-attenuation wall thickening; grade 4, wall thickening with enhancement; and grade 5, nodular enhancement or enhanced soft tissue. Two radiologists independently evaluated these grades on the post-chemotherapy CT. The area under the ROC curve (AUC) was used to evaluate diagnostic performance for pCR. Inter-reader agreement was assessed using the κ coefficient.

RESULTS

Twenty-seven patients (37 %) were confirmed with pCR. The AUCs for the assessment of pCR on UP CT were 0.85-0.86 for the two readers. Using absent or thin inner-layer enhancement as features to predict pCR, the sensitivity, specificity, positive predictive value, and negative predictive value were 74.1-81.5 %, 80.4-84.8 %, 71.0-74.1 %, and 84.8-88.1 % for both readers. The inter-reader agreement for grades ≤2 was almost perfect (κ = 0.83).

CONCLUSIONS

Absent or thin inner-layer enhancement on UP CT demonstrated high diagnostic performance and high inter-reader agreement for assessment of pCR after neoadjuvant chemotherapy in bladder cancer, and evaluation of this feature could improve the predictive ability of preoperative imaging for assessing pCR.

Diagnostic accuracy of retrospective application of the Vesical Imaging-Reporting and Data System: preliminary results

Objective

To evaluate the retrospective accuracy of the Vesical Imaging-Reporting and Data System (VI-RADS) in detecting muscle invasion in bladder cancer.

Materials and Methods

We investigated patients who underwent pelvic magnetic resonance imaging and were submitted to transurethral resection of a bladder tumor between 2015 and 2018. Thirty cases were reviewed by radiologists blinded to the final clinical stage. The VI-RADS score was applied and compared with the histopathological findings in the surgical specimen.

Results

Of the 30 patients with suspicious bladder lesions, 5 (16.6%) had benign histopathological findings, 17 (56.6%) had non-muscle-invasive bladder cancer, and 8 (26.6%) had muscle-invasive bladder cancer. The optimal criterion to detect muscle-invasive bladder cancer was a final VI-RADS score > 3, for which the sensitivity and specificity were 100% (95% CI: 56.0-100%) and 90.9% (95% CI: 69.3-98.4%), respectively.

Conclusion

The VI-RADS appears to estimate correctly the degree of muscle invasion in suspicious bladder lesions. However, prospective studies evaluating larger samples are needed in order to validate the method.

Preoperative imaging for locoregional staging of bladder cancer

Bladder cancer is the ninth most common cancer, expected to lead to an estimated 17,670 deaths in the United States in 2019. Clinical management and prognosis of bladder cancer mainly depend on the extent of locoregional disease, particularly whether bladder muscle is involved. Therefore, bladder cancer is often divided into superficial, non-muscle-invasive bladder cancer and muscle-invasive bladder cancer; the latter often prompts consideration for cystectomy. While precise staging prior to cystectomy is crucial, the optimal preoperative imaging modality used to stage the disease remains controversial. Transurethral resection of bladder tumor (TURBT) followed by computed tomography (CT) urography is the current recommended approach for staging bladder cancer but suffers from a high rate of understaging. We review the recent literature and compare different imaging modalities for assessing the presence of muscle invasion and lymph node involvement prior to cystectomy and highlight the advantages of each modality.

Advanced urothelial cancer: a radiology update

The recent genomic characterization of urothelial carcinoma by the Cancer Genome Atlas Project, made possible by the introduction of high throughput, reduced cost, and sequence analysis, has shed new insights on the biology of advanced disease. In addition, studies on imaging of advanced urothelial carcinoma have widened the knowledge on disease presentation and on pattern of metastatic spread and their correlation with the underlying biology of urothelial carcinoma. The wide range of treatments for advanced urothelial cancer, including combined chemotherapy regimens and immune checkpoint inhibitors, each result in treatment class-specific patterns of response and adverse events. Results of studies point to the need for a reliable biomarker, perhaps with imaging, that predicts prognosis and treatment response to systemic treatment, and can be used to select the most effective treatment while minimizing toxicity. This review of advanced urothelial cancer introduces the latest advances in genetic profiling, the current role of imaging, the radiographic appearance of treatment response and their toxicities, and details potential future areas of imaging research.

Update on MR urography (MRU): technique and clinical applications

Magnetic resonance imaging of the upper tract (pyelocalyces and ureters) or MR Urography (MRU) is technically possible and when performed correctly offers similar visualization of the upper tracts and for detection of non-calculous diseases of the collecting system similar specificity but with lower sensitivity compared to CTU. MRU provides the ability to simultaneously image the kidneys and urinary bladder with improved soft tissue resolution, better tissue characterization and when combined with assessment of the upper tract, a comprehensive examination of the urinary system. MRU requires meticulous attention to technical details and is a longer more demanding examination compared to CTU. Advances in MR imaging techniques including: parallel imaging, free-breathing motion compensation techniques and compressed sensing can dramatically shorten examination times and improve image quality and patient tolerance for the exam. This review article discusses updates in the MRU technique, summarizes clinical indications and opportunities for MRU in clinical practice and reviews advantages and disadvantages of MRU compared to CTU.

Orthopaedic metallic artefact reduction algorithm facilitates CT evaluation of the urinary tract after hip prosthesis

AIM

To examine the improvement in the visualisation of bladder and ureteric pathologies next to a hip prosthesis with metallic artefact reduction for orthopaedic implants (O-MAR).

MATERIALS AND METHODS

Thirty-four patients who underwent pelvic computed tomography (CT) for non-prosthesis-related causes were enrolled retrospectively. Portal venous phase scans were reconstructed both with standard iterative reconstruction (ITR) and with O-MAR. The density of the ureters and the bladder was measured at both sides in the plane of the prosthesis. A semi-quantitative score was also used to assess visibility. The R (version 3.4.1) package was used for statistical analysis.

RESULTS

The average (μ) density of the 41 prosthesis side ureters was significantly lower on ITR images (μ=-94.76±150.48 [±SD] HU) than on O-MAR images (μ=-13.40±36.37 HU; p<0.0004). The difference between the ITR and O-MAR (μ=-138.62±182.64 versus -35.55±40.21 HU; p<0.0003) was also significant at the prosthesis side of the bladder. The visibility of the prosthesis side ureters was improved: 53.7% was obscured on ITR series compared to 4.9% on O-MAR. The visibility score was also better across all levels (p<0.001) with O-MAR. In four cases (13%), the O-MAR images significantly changed the diagnosis: in two cases ureteric stones, in one case each a bladder stone and a bladder tumour were discovered.

CONCLUSIONS

O-MAR reconstruction of CT images significantly improves the visibility of the urinary tract adjacent to metallic hip implants. Thus, O-MAR is essential for detecting ureteric and bladder pathologies in patients with a hip prosthesis.

Diffusion-weighted magnetic resonance imaging in bladder cancer: comparison of readout-segmented and single-shot EPI techniques

Background

To evaluate whether readout-segment echo-planar imaging (RS-EPI) can provide better image quality in assessing bladder cancer than single-shot echo-planar imaging (SS-EPI) and to compare quantitative imaging parameters derived from both techniques.

Methods

Seventy patients with bladder lesions were enrolled and underwent diffusion-weighted imaging on a 3 Tesla magnetic resonance scanner using axial RS-EPI and SS-EPI techniques. Two observers independently assessed the susceptibility, detectability, motion artefacts and blurring of the images using qualitative scores. The signal-to-noise ratio (SNR), signal intensity ratio (SIR), contrast-to-noise ratio (CNR) and ADC values of the bladder lesions were measured and compared between the two techniques and between two observers. Qualitative and quantitative comparisons of image quality were performed using the Wilcoxon signed-rank test and paired t-test. In addition, the agreement of the ADC measurements was evaluated using ICC values and Bland-Altman plots.

Results

Sixty-eight patients were included in the final analysis. The scores of image susceptibility, detectability and blurring for RS-EPI were significantly higher than those for SS-EPI (all p < 0.05), while the motion artefact was not. There were significant differences between RS-EPI and SS-EPI in the CNR and SIR values (all p < 0.05) but not in the SNR or ADC values (all p > 0.05). The ICC values and Bland-Altman plots also showed excellent agreement between the measured ADC values of the bladder lesions.

Conclusions

The RS-EPI technique provides significantly better image quality in patients with bladder cancer than the SS-EPI technique, without a significant difference in the ADC value.

Use of Quantitative T2-Weighted and Apparent Diffusion Coefficient Texture Features of Bladder Cancer and Extravesical Fat for Local Tumor Staging After Transurethral Resection

OBJECTIVE. The purpose of this study was to determine whether quantitative T2-weighted imaging and apparent diffusion coefficient (ADC) texture features of bladder cancer and extravesical fat are predictive of muscle invasive bladder cancer (category ≥ T2) and extravesical (category ≥ T3) disease after transurethral resection of a bladder tumor (TURBT). MATERIALS AND METHODS. In this retrospective study, 36 patients (27 men, nine women; mean age, 71 years) were identified who underwent post-TURBT MRI followed by cystectomy without intervening treatment from August 2011 through October 2016. Texture features of bladder cancer and extravesical fat adjacent to the tumor on T2-weighted and ADC images were extracted and compared between category ≤ T2 versus ≥ T3 and category T1 versus ≥ T2 tumors by means of Kruskal-Wallis or Mann-Whitney U test. Multivariate logistic regression analysis was performed, and ROC curves were calculated. RESULTS. Twenty-six of the 36 (72%) tumors were ≥ T2, and 53% (19/36) were ≥ T3. In multivariate analysis, bladder cancer entropy on T2-weighted images (p = 0.006; odds ratio [OR], 4.56; 95% CI, 1.49-20.41; AUC, 0.85) and ADC maps (p = 0.019; OR, 2.24; 95% CI, 1.13-5.31; AUC, 0.80) and extravesical fat entropy on T2-weighted images (p = 0.005; OR, 17.50; 95% CI, 3.01-200.80; AUC, 0.84) and ADC maps (p = 0.002; OR, 6.54; 95% CI, 1.90-32.40; AUC, 0.82) remained greater for ≥ T3 than for ≤ T2 tumors. In multivariate analysis, bladder cancer entropy on ADC maps (p = 0.027; OR, 2.11; 95% CI, 1.08-5.03; AUC, 0.76) and extravesical fat entropy on T2-weighted images (p = 0.010; OR, 5.33; 95% CI, 1.25-3.79; AUC, 0.78) and ADC maps (p = 0.029; OR, 3.80; 95% CI, 1.25-16.97; AUC, 0.74) remained greater for category ≥ T2 compared with category T1 tumors. CONCLUSION. Greater entropy of primary bladder cancers and extravesicular fat was observed in category ≥ T3 than in category ≤ T2 and in category ≥ T2 than in category T1 tumors. MRI texture analysis can help with local bladder cancer staging in patients who have undergone TURBT and may serve as a biomarker for higher local category bladder cancers.

[Value of imaging in upper urinary tract tumors]

BACKGROUND

Staging of bladder cancer, hematuria as well as the evaluation of unclear findings of the kidneys and ureters are the most frequent indications for imaging of the upper urinary tract (UUT). Endourological assessment of the UUT is much more invasive compared to imaging of the bladder, raising the question of the optimal imaging technique. Several technical improvements regarding computed tomography (CT) as well as magnetic resonance imaging (MRI) were implemented in recent years.

OBJECTIVES

To compare the efficacy and limitations of the most important imaging techniques regarding the UUT.

MATERIALS AND METHODS

Systematic review of the literature and current German, European, and American guidelines regarding bladder cancer, urothelial carcinoma of the UUT and hematuria.

RESULTS

The CT-based urography has superseded excretory urography and is the first choice for imaging of the UUT. In case of contraindications, MRI is a feasible alternative. In all cases, a urography phase is indispensable.

CONCLUSIONS

Imaging of the UUT has to be used in a reasonable combination together with endourological methods and cytology. Optical coherence tomography, confocal laser endomicroscopy and scientific innovations such as radiomics might improve UUT imaging and differential diagnosis of UUT lesions in the future.

RETRACTED: Recommandations françaises du Comité de Cancérologie de l’AFU — Actualisation 2018—2020 : tumeurs de la vessie French ccAFU guidelines — Update 2018—2020: Bladder cancer

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Cet article est retiré de la publication à la demande des auteurs car ils ont apporté des modifications significatives sur des points scientifiques après la publication de la première version des recommandations. Le nouvel article est disponible à cette adresse: doi:10.1016/j.purol.2019.01.006. C’est cette nouvelle version qui doit être utilisée pour citer l’article. This article has been retracted at the request of the authors, as it is not based on the definitive version of the text because some scientific data has been corrected since the first issue was published. The replacement has been published at the doi:10.1016/j.purol.2019.01.006. That newer version of the text should be used when citing the article.

Bladder cancer local staging: multiparametric MRI performance following transurethral resection

PURPOSE

To evaluate the performance of multiparametric MRI (mpMRI) for the local staging of bladder cancer following transurethral resection of bladder tumor.

METHODS

This Institutional Review Board-approved, retrospective study identified 45 patients with pathology-proven bladder cancer who underwent transurethral resection followed by mpMRI between August 2011 and October 2016. Two radiologists reviewed each MRI independently and assigned T and N stage. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated for the presence of muscle invasion (T2 or higher), peri-vesical invasion (T3 or higher), and regional nodal disease compared to findings at cystectomy as the reference standard. Inter-observer agreement was measured using Cohen's κ coefficient.

RESULTS

Of 45 patients, 13% were stage T2, 27% T3, 16% T4; of 40 patients, 28% had regional nodal disease. Sensitivity, specificity, PPV, NPV, and accuracy of mpMRI for readers 1 and 2, respectively, were muscle invasion, 92% and 88%, 74% and 84%, 81% and 88%, 88% and 84%, 84% and 86%; peri-vesical invasion, 72% and 67%, 92% and 92%, 87% and 86%, 81% and 79%, 83% and 81%; regional nodal disease, 45% and 45%, 93% and 90%, 71% and 63%, 82% and 81%, 80% and 78%. Inter-observer agreement was good using all sequences.

CONCLUSIONS

mpMRI was both sensitive and specific in the detection of muscle invasive bladder cancer, and was specific but not sensitive for both peri-vesical invasion and nodal involvement. mpMRI may have a role at locally staging bladder cancer following transurethral resection.

A glance at imaging bladder cancer

Purpose

Early and accurate diagnosis of Bladder cancer (BCa) will contribute extensively to the management of the disease. The purpose of this review was to briefly describe the conventional imaging methods and other novel imaging modalities used for early detection of BCa and outline their pros and cons.

Methods

Literature search was performed on Pubmed, PMC, and Google scholar for the period of January 2014 to February 2018 and using such words as "bladder cancer, bladder tumor, bladder cancer detection, diagnosis and imaging".

Results

A total of 81 published papers were retrieved and are included in the review. For patients with hematuria and suspected of BCa, cystoscopy and CT are most commonly recommended. Ultrasonography, MRI, PET/CT using ¹⁸F-FDG or ¹¹C-choline and recently PET/MRI using ¹⁸F-FDG also play a prominent role in detection of BCa.

Conclusion

For initial diagnosis of BCa, cystoscopy is generally performed. However, cystoscopy can not accurately detect carcinoma insitu (CIS) and can not distinguish benign masses from malignant lesions. CT is used in two modes, CT and computed tomographic urography (CTU), both for dignosis and staging of BCa. However, they cannot differentiate T1 and T2 BCa. MRI is performed to diagnose invasive BCa and can differentiate muscle invasive bladder carcinoma (MIBC) from non-muscle invasive bladder carcinoma (NMIBC). However, CT and MRI have low sensitivity for nodal staging. For nodal staging PET/CT is preferred. PET/MRI provides better differentiation of normal and pathologic structures as compared with PET/CT. Nonetheless none of the approaches can address all issues related for the management of BCa. Novel imaging methods that target specific biomarkers, image BCa early and accurately, and stage the disease are warranted.