Treatment Strategy for Newly Diagnosed T1 High-grade Bladder Urothelial Carcinoma: New Insights and Updated Recommendations

Vesical Imaging-Reporting and Data System for Multiparametric MRI to Predict the Presence of Muscle Invasion for Bladder Cancer

BACKGROUND

The Vesical Imaging-Reporting and Data System (VI-RADS) is a newly developed system of bladder cancer staging with multiparametric MRI (mpMRI), which can be used to predict the presence of muscle invasion for bladder cancer.

PURPOSE

To evaluate the accuracy of three mpMRI series (T₂ WI, diffusion-weighted imaging [DWI], and dynamic contrast-enhanced image [DCEI]) and VI-RADS for diagnosing the muscle invasive bladder cancer (MIBC).

STUDY TYPE

Retrospective.

POPULATION

In all, 66 pathologically proven bladder cancers in 32 patients.

FIELD STRENGTH/SEQUENCE

Before the diagnostic MRI with an intramuscular antispasmodic agent, optimal bladder distension was confirmed. 3.0T MRI with T₂ WI, DWI, and DCEI.

ASSESSMENT

Three reviewers independently assessed and scored the bladder cancers in T₂ WI, DWI, and DCEI using a five-point score system. Based on the scores in the three sequences, reviewers scored each bladder cancer with reference to VI-RADS categories. We evaluated the diagnostic performance of each of three mpMRI sequences and the final VI-RADS categorization for diagnosing MIBC.

STATISTICAL TESTS

Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and the area under the curve (AUC) of each of three sequences separately and VI-RADS categorization for diagnosing the MIBC.

RESULTS

The diagnostic performances of each of the three mpMRI series and VI-RADS for diagnosing MIBC were excellent. Especially using the optimal cutoff score >3 for predicting MIBC on DWI, DCEI, and VI-RADS, the sensitivity, specificity, PPV, NPV, and AUC values were 90% (95% confidence interval [CI]: 0.56, 1.00), 100% (95% CI: 0.94, 1.00), 100% (95% CI: 0.66. 1.00), 98.3% (95% CI: 0.91, 1.00), and 0.95, respectively. DATA CONCLUSION: mpMRI based on VI-RADS can stratify patients with bladder cancer according to the presence of muscle invasion.

LEVEL OF EVIDENCE

3.

TECHNICAL EFFICACY STAGE

2. J. Magn. Reson. Imaging 2020;52:1249-1256.

T1 bladder cancer: current considerations for diagnosis and management

Stage T1 bladder cancers invade the lamina propria of the bladder and, despite sharing many of the genetic features of muscle-invasive bladder cancers, are classified as non-muscle-invasive or 'superficial' tumours. Yet, patients with T1 bladder cancer have an overall mortality of 33% and a cancer-specific mortality of 14% at three years after diagnosis, suggesting that these patients have a high risk of progression and, accordingly, require meticulous surgery, endoscopic surveillance and clinical decision-making. We hypothesize that the variability in the outcomes of patients with T1 bladder cancer is a result of both tumour heterogeneity and pathological staging, as well as inconsistencies in risk stratification, endoscopic resection and schedules of delivery of BCG. Owing to limitations in clinical staging, patients with T1 bladder cancer are at risk of both undertreatment with persistent use of BCG despite recurrence, and overtreatment with early cystectomy. Understanding the molecular features of T1 bladder cancers and how they respond to BCG therapy could improve biomarkers for risk stratification to align therapy with biological risk.

MicroRNAs Which Can Prognosticate Aggressiveness of Bladder Cancer

Bladder cancer (BC) is still characterized by a very high death rate in patients with this disease. One of the reasons for this is the lack of adequate markers which could help determine the biological potential of the tumor to develop into its invasive stage. It has been found that some microRNAs (miRNAs) correlate with disease progression. The purpose of this study was to identify which miRNAs can accurately predict the presence of BC and can differentiate low grade (LG) tumors from high grade (HG) tumors. The study included 55 patients with diagnosed bladder cancer and 30 persons belonging to the control group. The expression of seven selected miRNAs was estimated with the real-time PCR technique according to miR-103-5p (for the normalization of the results). Receiver operating characteristics (ROC) curves and the area under the curve (AUC) were used to evaluate the feasibility of using selected markers as biomarkers for detecting BC and discriminating non-muscle invasive BC (NMIBC) from muscle invasive BC (MIBC). For HG tumors, the relevant classifiers are miR-205-5p and miR-20a-5p, whereas miR-205-5p and miR-182-5p are for LG (AUC = 0.964 and AUC = 0.992, respectively). NMIBC patients with LG disease are characterized by significantly higher miR-130b-3p expression values compared to patients in HG tumors.

How to Treat a Patient with T1 High-grade Disease and No Tumour on Repeat Transurethral Resection of the Bladder?

A relatively young (64-yr old) long-term heavy smoker but otherwise very healthy man is diagnosed with a primary unifocal left-side tumour (urothelial, T1 high grade), but no lymphovascular invasion and no variant histology. We discuss whether treatment with intravesical bacillus Calmette-Guérin vaccine will be sufficient or early radical cystectomy is at least equally preferred regarding patient benefit, safety, and quality of life. PATIENT SUMMARY: A patient with a single high-grade T1 bladder tumour without aggressive features (eg, lymphovascular invasion or variant tumour aspects) will be adequately treated with bacillus Calmette-Guérin intravesical therapy delivered into the bladder, followed by 3 yr of maintenance. However, all decisions should be taken with the patient in a shared decision-making process, including a discussion regarding removal of the bladder.

Multiparametric MRI of the bladder: inter-observer agreement and accuracy with the Vesical Imaging-Reporting and Data System (VI-RADS) at a single reference center

OBJECTIVES

To evaluate accuracy and inter-observer variability using Vesical Imaging-Reporting and Data System (VI-RADS) for discrimination between non-muscle invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC).

METHODS

Between September 2017 and July 2018, 78 patients referred for suspected bladder cancer underwent multiparametric MRI of the bladder (mpMRI) prior to transurethral resection of bladder tumor (TURBT). All mpMRI were reviewed by two radiologists, who scored each lesion according to VI-RADS. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each VI-RADS cutoff. Receiver operating characteristics curves were used to evaluate the performance of mpMRI. The Ƙ statistics was used to estimate inter-reader agreement.

RESULTS

Seventy-five patients were included in the final analysis, 53 with NMIBC and 22 with MIBC. Sensitivity and specificity were 91% and 89% for reader 1 and 82% and 85% for reader 2 respectively when the cutoff VI-RADS > 2 was used to define MIBC. At the same cutoff, PPV and NPV were 77% and 96% for reader 1 and 69% and 92% for reader 2. When the cutoff VI-RADS > 3 was used, sensitivity and specificity were 82% and 94% for reader 1 and 77% and 89% for reader 2. Corresponding PPV and NPV were 86% and 93% for reader 1 and 74% and 91% for reader 2. Area under curve was 0.926 and 0.873 for reader 1 and 2 respectively. Inter-reader agreement was good for the overall score (Ƙ = 0.731).

CONCLUSIONS

VI-RADS is accurate in differentiating MIBC from NMIBC. Inter-reader agreement is overall good.

KEY POINTS

• Traditionally, the local staging of bladder cancer relies on transurethral resection of bladder tumor. • However, transurethral resection of bladder tumor carries a significant risk of understaging a cancer; therefore, more accurate, faster, and non-invasive staging techniques are needed to improve outcomes. • Multiparametric MRI has proved to be the best imaging modality for local staging; therefore, its use in suitable patients has the potential to expedite radical treatment when necessary and non-invasive diagnosis in patients with poor fitness.

The rational and benefits of the second look transurethral resection of the bladder for T1 high grade bladder cancer

The second look transurethral resection of the bladder (TURB) represents a fundamental step in the treatment of papillary non-muscle invasive bladder cancer (NMIBC); it is therefore recommended by all guidelines. However, not all the literature agrees on its staging value and its ability to improve oncological outcomes of patients. Therefore, the purpose of this review is to evaluate the strengths and weaknesses of second look TURB, trying to depict its evolving role in the management of high grade NMIBC. Using Medline, a non-systematic review was performed including articles between January 2000 and June 2018. English language original articles, reviews and editorials were selected based on their clinical relevance. To date, TURB seems to be largely inadequate in retrieving a correct diagnosis and in removing all tumor tissue. Second look TURB maximizes staging accuracy, allows to clear residual cancer and yields prognostic advantages allowing key information to identify possible candidates for immediate radical cystectomy for very high risk T1HG tumors. Moreover, it seems to have a therapeutic benefit by improving recurrence- and progression-free survivals. However, few recent large studies showed that these advantages seem to be limited to patients without detrusor muscle present at first resection. Similarly, the presence of residual disease and the risk of upstaging are related to the presence of detrusor muscle in specimen. It could well be that in the future the presence of detrusor muscle would be a quality criteria to avoid an unnecessary second look TURB as shown by recent studies using the en-bloc resection technique. Finally, it has to be underlined that this is a surgical procedure not free of risks and complications and with a non-negligible impact on patients’ quality of life, waiting lists and healthcare costs. Therefore, future studies trying to identify the criteria that may better allow which patients to select for a second look TURB while avoiding an unnecessary intervention with possible risks and associated cost are needed to allow a personalized approach to even this one size fits all strategy.

Trial Watch: Toll-like receptor agonists in cancer immunotherapy

Toll-like receptor (TLR) agonists demonstrate therapeutic promise as immunological adjuvants for anticancer immunotherapy. To date, three TLR agonists have been approved by US regulatory agencies for use in cancer patients. Additionally, the potential of hitherto experimental TLR ligands to mediate clinically useful immunostimulatory effects has been extensively investigated over the past few years. Here, we summarize recent preclinical and clinical advances in the development of TLR agonists for cancer therapy.