A Second-Look TUR in T1 Transitional Cell Carcinoma: Why?

Development of deep learning model for diagnosing muscle-invasive bladder cancer on MRI with vision transformer

Rationale and objectives

To develop and validate a deep learning (DL) model to automatically diagnose muscle-invasive bladder cancer (MIBC) on MRI with Vision Transformer (ViT).

Materials and methods

This multicenter retrospective study included patients with BC who reported to two institutions between January 2016 and June 2020 (training dataset) and a third institution between May 2017 and May 2022 (test dataset). The diagnostic model for MIBC and the segmentation model for BC on MRI were developed using the training dataset with 5-fold cross-validation. ViT- and convolutional neural network (CNN)-based diagnostic models were developed and compared for diagnostic performance using the area under the curve (AUC). The performance of the diagnostic model with manual and auto-generated regions of interest (ROImanual and ROIauto, respectively) was validated on the test dataset and compared to that of radiologists (three senior and three junior radiologists) using Vesical Imaging Reporting and Data System scoring.

Results

The training and test datasets included 170 and 53 patients, respectively. Mean AUC of the top 10 ViT-based models with 5-fold cross-validation outperformed those of the CNN-based models (0.831 ± 0.003 vs. 0.713 ± 0.007-0.812 ± 0.006, p < .001). The diagnostic model with ROImanual achieved AUC of 0.872 (95 % CI: 0.777, 0.968), which was comparable to that of junior radiologists (AUC = 0.862, 0.873, and 0.930). Semi-automated diagnosis with the diagnostic model with ROIauto achieved AUC of 0.815 (95 % CI: 0.696, 0.935).

Conclusion

The DL model effectively diagnosed MIBC. The ViT-based model outperformed CNN-based models, highlighting its utility in medical image analysis.

Enhancing recurrence risk prediction for bladder cancer using multi-sequence MRI radiomics

OBJECTIVE

We aimed to develop a radiomics-clinical nomogram using multi-sequence MRI to predict recurrence-free survival (RFS) in bladder cancer (BCa) patients and assess its superiority over clinical models.

METHODS

A retrospective cohort of 229 BCa patients with preoperative multi-sequence MRI was divided into a training set (n = 160) and a validation set (n = 69). Radiomics features were extracted from T2-weighted images, diffusion-weighted imaging, apparent diffusion coefficient, and dynamic contrast-enhanced images. Effective features were identified using the least absolute shrinkage and selection operator (LASSO) method. Clinical risk factors were determined via univariate and multivariate Cox analysis, leading to the creation of a radiomics-clinical nomogram. Kaplan-Meier analysis and log-rank tests assessed the relationship between radiomics features and RFS. We calculated the net reclassification improvement (NRI) to evaluate the added value of the radiomics signature and used decision curve analysis (DCA) to assess the nomogram's clinical validity.

RESULTS

Radiomics features significantly correlated with RFS (log-rank p < 0.001) and were independent of clinical factors (p < 0.001). The combined model, incorporating radiomics features and clinical data, demonstrated the best prognostic value, with C-index values of 0.853 in the training set and 0.832 in the validation set. Compared to the clinical model, the radiomics-clinical nomogram exhibited superior calibration and classification (NRI: 0.6768, 95% CI: 0.5549-0.7987, p < 0.001).

CONCLUSION

The radiomics-clinical nomogram, based on multi-sequence MRI, effectively assesses the BCa recurrence risk. It outperforms both the radiomics model and the clinical model in predicting BCa recurrence risk.

CRITICAL RELEVANCE STATEMENT

The radiomics-clinical nomogram, utilizing multi-sequence MRI, holds promise for predicting bladder cancer recurrence, enhancing individualized clinical treatment, and performing tumor surveillance.

KEY POINTS

• Radiomics plays a vital role in predicting bladder cancer recurrence. • Precise prediction of tumor recurrence risk is crucial for clinical management. • MRI-based radiomics models excel in predicting bladder cancer recurrence.

Fremantle protocol: Multicenter clinical outcomes for a pragmatic protocol for intravesical bacillus Calmette-Guerin

OBJECTIVES

To examine the utility and efficacy of a multifaceted protocol for the administration of intravesical bacillus Calmette-Guerin (BCG) for non-muscle-invasive bladder cancer (NMIBC).

SUBJECTS AND METHODS

A multicenter retrospective review was conducted among 83 patients undergoing Fremantle protocol intravesical BCG for NMIBC within 4 major hospitals in Western Australia between January 2016 and December 2018. The Fremantle protocol consists of weekly BCG instillations for 6 weeks during the induction phase, followed by monthly BCG instillations for 10 months during the maintenance phase with integrated clearance-to-proceed algorithms for urine MSU checks, flexible cystoscopies performed at 3 monthly intervals during maintenance BCG, and repeat GA cystoscopies with four quadrant bladder biopsies routinely obtained following the completion of induction and maintenance treatment.

RESULTS

For patients undergoing Fremantle protocol BCG, 98.8% (82/83) and 75.9% (63/83) of patients completed their induction and maintenance courses of BCG, respectively. Induction BCG was delivered over a median duration of 35 days (range 34-84 days), and maintenance BCG was delivered over a median duration of 266 days (range 1-682 days). The tumor recurrence rate was 10.8% (9/83) at the time of post-induction biopsies, 2.4% (2/83) during maintenance treatment, 0% (0/60) at the time of post-maintenance biopsies, and 8.8% (5/57) after a median further follow-up of 16 months (range 0-51 months).

CONCLUSION

The Fremantle protocol appears to be a safe and effective BCG regimen with several advantages over other BCG protocols, including high completion rates, low recurrence rates, and being highly pragmatic.

Comparison of hexaminolevulinate (HAL) -guided versus white light transurethral resection for NMIBC: A systematic review and meta-analysis of randomized controlled trials

PURPOSE

We systematically reviewed the effectiveness of hexaminolevulinic acid (HAL) after traditional light cystoscopy vs. only white light cystoscopy (WLC) on nonmuscle-invasive bladder cancer (NMIBC) clinical outcomes.

METHODS

Systematic literature searches of PubMed, Embase, Web of Science, and the Cochrane database and reference lists were performed. A total of 12 randomized controlled trials (RCTs) of HAL fluorescent cystoscopy (FC) and WLC vs. white light cystoscopy alone for the diagnosis of initial or recurrent bladder cancer that reported bladder cancer recurrence, progression, recurrence-free survival (RFS), and other effects were selected for review.

RESULTS

Our results included 2,775 patients identified for analysis and showed that the HAL group had a lower recurrence rate than the white light cystoscopy group with a statistically significant difference (RR=0.77, 95% CI 0.69-0.85. P < 0.05), and this advantage still existed for patients receiving intravesical chemotherapy. There was also a statistically significant difference in favour of fluorescent cystoscopy in recurrence-free survival and progression rate (HR=0.79, 95% CI 0.67-0.92. P < 0.05, RR = 0.63, 95% CI 0.43-0.94. P < 0.05, respectively). The time to first recurrence was not significantly different from that in the WLC group (SMD=0.73, 95% CI, -0.39-1.85. P = 0.2). And the HAL group did not have a significantly reduced residual tumor rate (RR=0.59, 95% CI 0.23-1.51. P = 0.27).

CONCLUSIONS

Fluorescent cystoscopy was associated with a reduced risk of bladder cancer recurrence and reduced progression rate; it also has advantages for RFS. However, there was no significant difference in the rate of residual tumor and the time of first recurrence. More studies are needed to better understand the effects of the photosensitizer used on NMIBC patients.

Role of Macroscopic Image Enhancement in Diagnosis of Non-Muscle-Invasive Bladder Cancer: An Analytical Review

Early diagnosis of non-muscle-invasive bladder cancer (NMIBC) is of paramount importance to prevent morbidity and mortality due to bladder cancer. Although white light imaging (WLI) cystoscopy has long been considered the gold standard in the diagnosis of bladder cancer, it can miss lesions in a substantial percentage of patients and is very likely to miss carcinoma in situ and dysplasia. Tumor margin detection by WLI can be inaccurate. Moreover, WLI could, sometimes, be inadequate in distinguishing inflammation and malignancy. To improve the diagnostic efficacy of cystoscopy, various optical image enhancement modalities have been studied. These image enhancement modalities have been classified as macroscopic, microscopic, or molecular. Photodynamic diagnosis (PDD), narrow band imaging (NBI), and Storz image 1 S enhancement (formerly known as SPIES) are macroscopic image enhancement modalities. A relevant search was performed for literature describing macroscopic image enhancement modalities like PDD, NBI, and image 1 S enhancement. The advantages, limitations, and usefulness of each of these in the diagnosis of bladder cancer were studied. Photodynamic diagnosis requires intravesical instillation of a photosensitizing agent and a special blue light cystoscope system. PDD has been shown to be more sensitive than WLI in the detection of bladder cancer. It is superior to WLI in the detection of flat lesions. Bladder tumor resection (TURBT) by PDD results in more complete resection and reduced recurrence rates. PDD-guided TURBT may have some role in reducing the risk of progression. Narrow band imaging provides increased contrast between normal and abnormal tissues based on neovascularization, thereby augmenting WLI. NBI requires a special light source. There is no need for intravesical contrast instillation. NBI is superior to WLI in the detection of bladder cancer. The addition of NBI to WLI improves the detection of flat lesions like carcinoma in situ. NBI is not useful in predicting invasive tumors or grades of tumors. NBI-directed TURBT reduces recurrence rates and recurrence free survival. But its efficacy in retarding progression is unproven. Image 1 S-enhancement utilizes software-based image enhancement modes without the need for a special light source or intravesical contrast instillation. This system provides high-quality images and identifies additional abnormal-looking areas. Another advantage of this system is simultaneous side-by-side visualization of WLI and enhanced image, providing WLI images as the control for comparison. As with PDD, S-enhancement produces a lower rate of a missed bladder cancer diagnosis. The system significantly improves the diagnosis of NMIBC. The sensitivity and negative predictive value of image 1 S enhancement increase with the increase in cancer grade. A negative test by S-enhancement effectively rules out NMIBC. All the image enhancement modalities have proven their utility in improving detection and short-term cancer control. But none of these modalities have proven their utility in delaying progression, or in long-term cancer control. Cancer progression and long-term control are governed by the biological nature of cancer cells. Early detection by optical enhancement may not be of utility in this regard. Well-designed studies are needed to establish the efficacy of these modalities in the evaluation of patients with bladder cancer. The last word, in this regard, is yet to be written.

Study Progress of Noninvasive Imaging and Radiomics for Decoding the Phenotypes and Recurrence Risk of Bladder Cancer

Urinary bladder cancer (BCa) is a highly prevalent disease among aged males. Precise diagnosis of tumor phenotypes and recurrence risk is of vital importance in the clinical management of BCa. Although imaging modalities such as CT and multiparametric MRI have played an essential role in the noninvasive diagnosis and prognosis of BCa, radiomics has also shown great potential in the precise diagnosis of BCa and preoperative prediction of the recurrence risk. Radiomics-empowered image interpretation can amplify the differences in tumor heterogeneity between different phenotypes, i.e., high-grade vs. low-grade, early-stage vs. advanced-stage, and nonmuscle-invasive vs. muscle-invasive. With a multimodal radiomics strategy, the recurrence risk of BCa can be preoperatively predicted, providing critical information for the clinical decision making. We thus reviewed the rapid progress in the field of medical imaging empowered by the radiomics for decoding the phenotype and recurrence risk of BCa during the past 20 years, summarizing the entire pipeline of the radiomics strategy for the definition of BCa phenotype and recurrence risk including region of interest definition, radiomics feature extraction, tumor phenotype prediction and recurrence risk stratification. We particularly focus on current pitfalls, challenges and opportunities to promote massive clinical applications of radiomics pipeline in the near future.

A nomogram combined with radiomics features, albuminuria, and metabolic syndrome to predict the risk of myometrial invasion of bladder cancer

Background

To establish a preoperative prediction model of myometrial invasion of bladder cancer (BC) based on the radiomics characteristics of multi-parameter thin-slice enhanced computed tomography (CT) imaging.

Methods

Data from 100 patients with BC were analyzed retrospectively. The patients were divided into two groups: muscular invasive BC and non-muscular invasive BC. The tumor region was segmented from enhanced CT images (arterial- and venous-phase calibration maps) of all patients using Slicer-3D software. We extracted 1,223 texture features from tumor image data based on the shape and gray-level co-occurrence matrix, gray size region matrix, gray run-length matrix, adjacent gray difference matrix, and gray correlation matrix. The patients were randomly divided into a training group (n=70) and a verification group (n=30) in a 7:3 ratio. Interclass correlation coefficients >0.75, least absolute shrinkage, and selection operator regression were used for feature selection. The prediction model was established by combining Rad-score, independent clinical factors, and support vector machine (SVM), and a radiomics nomogram was constructed. The nomogram was tested using the consistency index, calibration curve, time-dependent receiver operating characteristic curve, and clinical decision curve to predict the myometrial invasion of the bladder preoperatively.

Results

Six radiomics features that were significantly related to myometrial invasion of BC were selected to construct a predictive model. The area under the curve (AUC) values of training group and verification group based on SVM were 0.898 (95% CI: 0.820–0.976) and 0.702 (95% CI: 0.495–0.909), respectively. Single factor and multiple factor analysis showed that albuminuria (95% CI: 0.243–2.206, P=0.0014) and metabolic syndrome (95% CI: 0.850–2.935, P<0.001) were independent influencing factors of BC myometrial invasion. Clinical factors and 11 radiomics features were used to construct a comprehensive model for predicting the pathological grade of BC (radiomics + clinical). After a comprehensive comparison, we found that the overall effectiveness of the model (radiomics + clinical) was the highest (AUC =0.8457).

Conclusions

Based on the multi-parameter thin-layer enhanced CT radiomics feature can be used as a potential independent predictor of BC myometrial invasion, the model based on parameters can initially quantitatively characterize the risk of myometrial invasion, and has excellent potential for predicting myometrial invasion of BC.

Repeated 5-aminolevulinic Acid Instillations During Follow-up in Non-muscle-invasive Bladder Cancer: A Randomized Study

BACKGROUND/AIM

Non-muscle invasive bladder carcinoma (NMIBC) is highly recurrent. We studied if 5-aminolevulinic acid (5-ALA) instillations before transurethral resection of bladder tumours (TURBT) and cystoscopy extend the time to recurrence during follow-up with NMIBC patients.

PATIENTS AND METHODS

A prospective multicenter study enrolled 328 NMIBC patients. All TURBTs and control cystoscopies during the one-year study period were done with or without 5-ALA instillations. The primary endpoint was time to recurrence. The secondary endpoints were time to recurrence after 7.5, 10.5, and 13.5 months and the number of patients with progressive disease.

RESULTS

The overall median follow-up time was 80.4 and 87.0 months for the control and study groups, respectively. There was no statistical difference in time to first recurrence between the two groups.

CONCLUSION

We could not obtain significant differences between the control and 5-ALA groups in tumour recurrence among patients with NMIBC.

Comparison of Re-TUR Results in Primary Patients with Non-muscle-Invasive Bladder Cancer (NMIBC) of Low, Intermediate, and High-risk for Recurrence Based on the EORTC Scoring System

Background: Bladder cancer is the second most common urologic malignancy. Transurethral resection (TUR) is the standard initial treatment for non-muscle-invasive bladder cancer (NMIBC). The high prevalence of residual tumor in some patients has necessitated repeat TUR (re-TUR). Previous studies have shown the quality of primary resection to impact re-TUR outcomes, but the role of tumor biology remains unclear. Objectives: This study aimed to evaluate the impact of tumor biology on re-TUR results in primary (non-recurrent) patients with superficial bladder tumors. Methods: We studied a cohort of consecutive primary patients with superficial bladder cancer undergoing resection and routine re-TUR between March 2018 and February 2019 at our unit. Patients with TaG1 or T2 on primary pathologic report, deliberately incomplete initial resection, or absence of detrusor muscle on the initial specimen were excluded from the study. Re-TUR was performed in the sixth week. All procedures were performed by the same surgeon. The patients were divided into three groups according to the European Organization for Research and Treatment of Cancer (EORTC) risk scoring system and compared for recurrence of NMIBC. Results: Of 58 primary patients, 16 were classified as low-risk, 32 as intermediate-risk, and 10 as high-risk. The mean age of subjects was 62.1 years. Residual tumor was detected on re-TUR in 19 (32.7%) cases. Also, 3 (5.2%) cases entailed stage progression to pT2, all of whom belonged to the high-risk group. Residual tumor rate was 0%, 40.6%, and 60% in the low-, intermediate-, and high-risk groups, respectively. In addition, 13 patients had macroscopic residual. Conclusions: Despite the modest study size, our results suggest that tumor biology might have an impact on residual tumor characteristics, and the EORTC scoring system may help to predict the risk of progression and residual tumor rate on re-TUR.

A multiparametric MRI-based CAD system for accurate diagnosis of bladder cancer staging

Appropriate treatment of bladder cancer (BC) is widely based on accurate and early BC staging. In this paper, a multiparametric computer-aided diagnostic (MP-CAD) system is developed to differentiate between BC staging, especially T1 and T2 stages, using T2-weighted (T2W) magnetic resonance imaging (MRI) and diffusion-weighted (DW) MRI. Our framework starts with the segmentation of the bladder wall (BW) and localization of the whole BC volume (V_t) and its extent inside the wall (V_w). Our segmentation framework is based on a fully connected convolution neural network (CNN) and utilized an adaptive shape model followed by estimating a set of functional, texture, and morphological features. The functional features are derived from the cumulative distribution function (CDF) of the apparent diffusion coefficient. Texture features are radiomic features estimated from T2W-MRI, and morphological features are used to describe the tumors' geometric. Due to the significant texture difference between the wall and bladder lumen cells, V_t is parcelled into a set of nested equidistance surfaces (i.e., iso-surfaces). Finally, features are estimated for individual iso-surfaces, which are then augmented and used to train and test machine learning (ML) classifier based on neural networks. The system has been evaluated using 42 data sets, and a leave-one-subject-out approach is employed. The overall accuracy, sensitivity, specificity, and area under the receiver operating characteristics (ROC) curve (AUC) are 95.24%, 95.24%, 95.24%, and 0.9864, respectively. The advantage of fusion multiparametric iso-features is highlighted by comparing the diagnostic accuracy of individual MRI modality, which is confirmed by the ROC analysis. Moreover, the accuracy of our pipeline is compared against other statistical ML classifiers (i.e., random forest (RF) and support vector machine (SVM)). Our CAD system is also compared with other techniques (e.g., end-to-end convolution neural networks (i.e., ResNet50).

Primary Complete Transurethral Resection of Bladder Tumor Using Photodynamic Diagnosis for High-Risk Nonmuscle Invasive Bladder Cancer: Is a Restaging Photodynamic Transurethral Resection Really Necessary?

Objectives: To evaluate the risk of residual tumor and tumor upstaging during a second resection after primary complete transurethral resection of bladder tumor (TURBT) using photodynamic diagnosis (PDD) for high-risk nonmuscle invasive bladder cancer (NMIBC). Patients and Methods: From January 2014 to March 2020, a single-institutional study was conducted including consecutive patients with high-risk NMIBC (T1 and/or cis and/or high grade) who underwent a restaging transurethral resection (reTUR) within 12 weeks after a primary complete resection. Each TURBT was performed using blue light after intravesical instillation of hexaminolevulinate. The primary endpoint was detection of residual tumor at reTUR, proved with positive pathology report. Results: A total of 109 consecutive patients with high-risk NMIBC underwent reTUR after a primary complete blue light resection. Pathologic evaluation of the surgical specimens of the primary TURBT revealed stage T1 and high-grade tumors in 69 (68.3%) and 108 (99%) patients, respectively, and concomitant carcinoma in situ was found in 45 patients (41.3%). The median time to reTUR was 8 (6-10) weeks. Residual tumor was detected histopathologically in 64 of 109 patients (58.7%) at the second TURBT with PDD. In five of these patients (4.5%), initial T1 tumors were upstaged to T2 tumors. Conclusions: We examined a contemporary series of patients undergoing reTUR with PDD as management of high-risk NMIBC proven at the first blue light resection. We reported a 54.2% risk of disease persistence and a 4.5% risk of understaging in T1 tumors. These findings support that reTUR is still necessary after initial complete TURBT with PDD. Further studies are needed to assess the long-term oncologic outcomes of reTUR with PDD.

Effects of fluorescent light cystoscopy in non-muscle-invasive bladder cancer: A systematic review and meta-analysis

BACKGROUND

The benefits of fluorescent light (FL) cystoscopy with 5-aminolevulinic acid (5-ALA) or hexaminolevulinate (HAL) in non-muscle-invasive bladder cancer (NMIBC) have been mentioned in many trials. Meanwhile, several problems need to be addressed such as the rate of residual disease following these procedures.

OBJECTIVE

To assess the effects of FL cystoscopy compared with white light (WL) cystoscopy on the rate of residual Ta, T1, and carcinoma in situ (CIS) tumors, recurrence-free survival (RFS) and progression-free survival (PFS).

METHODS

A search in the databases PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure (CNKI) and China Biology Medicine (CBM) was undertaken. Studies were included if their outcomes included the residual tumor rate, PFS or RFS. The data was analyzed by REVMAN 5.3 and STATA 14.0.

RESULTS

The residual tumor rate of the FL group was lower than that of the WL group (relative risk [RR] 0.42; 95 % confidence interval [CI] 0.26-0.80; P = 0.007), which was consistent with the residual Ta rate (RR 0.44; 95 % CI 0.28-0.69; P = 0.0004), the residual T1 rate (RR 0.42; 95 % CI 0.21-0.83; P = 0.01) and the residual CIS rate (RR 0.39; 95 % CI 0.19-0.80; P = 0.01). RFS at the 12-month follow-up (RR 1.15; 95 % CI 1.08-1.28; P = 0.0002) and 24-month follow-up (RR 1.26; 95 % CI 1.17-1.35; P < 0.00001) in the FL group was significantly higher than that in the WL group. However, no statistically significant differences were found in PFS at the 12-month follow-up (RR 1.01; 95 % CI 0.99-1.03; P = 0.17) or 24-month follow-up (RR 1.00; 95 % CI 0.97-1.03; P = 0.95).

CONCLUSION

FL cystoscopy was related to a reduced residual tumor rate compared with WL cystoscopy in NMIBC, which was also consistent with the Ta, T1 and residual CIS rates. RFS was higher in patients with FL cystoscopy at the 12- to 24-month follow-up.

Elaboration of a multisequence MRI-based radiomics signature for the preoperative prediction of the muscle-invasive status of bladder cancer: a double-center study

OBJECTIVES

To develop a multisequence MRI-based radiomics signature for the preoperative prediction of the muscle-invasive status of bladder cancer (BCa).

METHODS

This retrospective study involved 106 eligible patients from two independent clinical centers. All patients underwent a preoperative 3.0 T MRI scan with T2-weighted image (T2WI) and multi-b-value diffusion-weighted image (DWI) sequences. In total, 1404 radiomics features were extracted from the largest region of the reported tumor locations on the T2WI, DWI, and corresponding apparent diffusion coefficient map (ADC) of each patient. A radiomics signature, namely the Radscore, was then generated using the recursive feature elimination approach and a logistic regression algorithm in a training cohort (n = 64). Its performance was then validated in an independent validation cohort (n = 42). The primary imaging and clinical factors in conjunction with the Radscore were used to determine whether the performance could be further improved.

RESULTS

The Radscore, generated by 36 selected radiomics features, demonstrated a favorable ability to predict muscle-invasive BCa status in both the training (AUC 0.880) and validation (AUC 0.813) cohorts. Subsequently, integrating the two independent predictors (including the Radscore and MRI-determined tumor stalk) into a nomogram exhibited more favorable discriminatory performance, with the AUC improved to 0.924 and 0.877 in both cohorts, respectively.

CONCLUSIONS

The proposed multisequence MRI-based radiomics signature alone could be an effective tool for quantitative prediction of muscle-invasive status of BCa. Integrating the Radscore with MRI-determined tumor stalk could further improve the discriminatory power, realizing more accurate prediction of nonmuscle-invasive and muscle-invasive BCa.

KEY POINTS

• DWI is superior to T2WI sequence in reflecting the heterogeneous differences between NMIBC and MIBC, and multisequence MRI helps in the preoperative prediction of muscle-invasive status of BCa. • Co-occurrence (CM), run-length matrix (RLM), and gray-level size zone matrix (GLSZM) features were the favorable feature categories for the prediction of muscle-invasive status of BCa. • The Radscore (proposed multisequence MRI-based radiomics signature) helps predict preoperatively muscle invasion. Combination with the MRI-determined tumor stalk further improves prediction.

Study Progress of Radiomics With Machine Learning for Precision Medicine in Bladder Cancer Management

Bladder cancer is a fatal cancer that happens in the genitourinary tract with quite high morbidity and mortality annually. The high level of recurrence rate ranging from 50 to 80% makes bladder cancer one of the most challenging and costly diseases to manage. Faced with various problems in existing methods, a recently emerging concept for the measurement of imaging biomarkers and extraction of quantitative features called "radiomics" shows great potential in the application of detection, grading, and follow-up management of bladder cancer. Furthermore, machine-learning (ML) algorithms on the basis of "big data" are fueling the powers of radiomics for bladder cancer monitoring in the era of precision medicine. Currently, the usefulness of the novel combination of radiomics and ML has been demonstrated by a large number of successful cases. It possesses outstanding strengths including non-invasiveness, low cost, and high efficiency, which may serve as a revolution to tumor assessment and emancipate workforce. However, for the extensive clinical application in the future, more efforts should be made to break down the limitations caused by technology deficiencies, inherent problems during the process of radiomic analysis, as well as the quality of present studies.

The prognostic value of routine second transurethral resection in patients with newly diagnosed stage pT1 non-muscle-invasive bladder cancer: results from randomized 10-year extension trial

PURPOSE

To evaluate the impact of routine second TUR on the long-term outcome of patients with newly diagnosed stage pT1 non-muscle-invasive bladder cancer (NMIBC) MATERIAL AND METHODS: A total of 210 patients (mean age 62.1 years, 89.5% were males) with stage pT1 NMIBC who underwent first TUR were prospectively randomized into two groups including second TUR (n = 105) and no second TUR (n = 105) groups. Data on recurrence, disease progression, 7-year and 10-year recurrence-free survival (RFS), progression-free survival (PFS) and overall survival (OS) were recorded.

RESULTS

The median follow-up time was 119 months (IQR 65-168). Per-protocol (PP) analysis revealed that compared to patients without second TUR, patients with second TUR had significantly higher 5-year, 7-year and 10-year rates for RFS (59.4%, 57.9% and 54.8% vs. 36.3%, 31.7% and 26.8%, respectively, p < 0.001) and PFS (93.3%, 91.9% and 90.4% vs. 74.0%, 71.4% and 68.5%, respectively, p < 0.001). According to PP and intention-to-treat (ITT) analyses, the 10-year OS rate was significantly higher in patients with second TUR (59.1 vs. 40.8%, p = 0.004). Multivariate analysis revealed that undergoing second TUR (OR 1.661, 95% CI 1.156-2.385, p = 0.006) was an independent determinant of prolonged OS.

CONCLUSIONS

In conclusion, these findings indicate the prognostic value of second TUR in stage pT1 NMIBC patients, not only for RFS and PFS advantages but also for the long-term OS advantage. Therefore, second TUR should be routinely performed in all stage pT1 NMIBC patients with life expectancy of at least 10 years, given the positive contribution to all oncological outcomes.

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.

Quantitative Identification of Nonmuscle-Invasive and Muscle-Invasive Bladder Carcinomas: A Multiparametric MRI Radiomics Analysis

BACKGROUND

Preoperative discrimination between nonmuscle-invasive bladder carcinomas (NMIBC) and the muscle-invasive ones (MIBC) is very crucial in the management of patients with bladder cancer (BC).

PURPOSE

To evaluate the discriminative performance of multiparametric MRI radiomics features for precise differentiation of NMIBC from MIBC, preoperatively.

STUDY TYPE

Retrospective, radiomics.

POPULATION

Fifty-four patients with postoperative pathologically proven BC lesions (24 in NMIBC and 30 in MIBC groups) were included.

FIELD STRENGTH/SEQUENCE

3.0T MRI/T₂ -weighted (T₂ W) and multi-b-value diffusion-weighted (DW) sequences.

ASSESSMENT

A total of 1104 radiomics features were extracted from carcinomatous regions of interest on T₂ W and DW images, and the apparent diffusion coefficient maps. Support vector machine with recursive feature elimination (SVM-RFE) and synthetic minority oversampling technique (SMOTE) were used to construct an optimal discriminative model, and its performance was evaluated and compared with that of using visual diagnoses by experts.

STATISTICAL TESTS

Chi-square test and Student's t-test were applied on clinical characteristics to analyze the significant differences between patient groups.

RESULTS

Of the 1104 features, an optimal subset involving 19 features was selected from T₂ W and DW sequences, which outperformed the other two subsets selected from T₂ W or DW sequence in muscle invasion discrimination. The best performance for the differentiation task was achieved by the SVM-RFE+SMOTE classifier, with averaged sensitivity, specificity, accuracy, and area under the curve of receiver operating characteristic of 92.60%, 100%, 96.30%, and 0.9857, respectively, which outperformed the diagnostic accuracy by experts.

DATA CONCLUSION

The proposed radiomics approach has potential for the accurate differentiation of muscle invasion in BC, preoperatively. The optimal feature subset selected from multiparametric MR images demonstrated better performance in identifying muscle invasiveness when compared with that from T₂ W sequence or DW sequence only.

LEVEL OF EVIDENCE

3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1489-1498.

Impact of Occupational Exposures and Genetic Polymorphisms on Recurrence and Progression of Non-Muscle-Invasive Bladder Cancer

Introduction: Additional or better markers are needed to guide the clinical monitoring of patients with non-muscle-invasive bladder cancer (NMIBC). Aim: To investigate the influence of occupational exposures and genetic polymorphisms on recurrence and progression of NMIBC. Methods: The study includes 160 NMIBC patients. We collected on questionnaire information on demographic variables, lifetime smoking history, lifetime history of occupational exposure to aromatic amines and polycyclic aromatic hydrocarbons. Genetic polymorphism (glutathione S-transferase M1; T1; P1 (GSTM1; GSTT1; GSTP1); N-acetyltransferase 1; 2 (NAT1; NAT2); cytochrome P450 1B1 (CYP1B1); sulfotransferase 1A1 (SULT1A1); myeloperoxidase (MPO); catechol-O-methyltransferase (COMT); manganese superoxide dismutase (MnSOD); NAD(P)H:quinone oxidoreductase (NQO1); X-ray repair cross-complementing group 1; 3 (XRCC1; XRCC3) and xeroderma pigmentosum complementation group (XPD)) was assessed in peripheral blood lymphocytes. DNA adducts were evaluated by 32P-postlabeling. Predictors of recurrence (histological confirmation of a newly found bladder tumor) and progression (transition of tumor from low-grade to high-grade and/or increase in TNM stage) were identified by multivariate Cox proportional hazard regression with stepwise backward selection of independent variables. Hazard ratios (HR) with 95% confidence interval (95%CI) and two-tail probability of error (p-value) were estimated. Results: The risk of BC progression decreased with the homozygous genotype “ValVal” of both COMT and MnSOD (HR = 0.195; 95%CI = 0.060 to 0.623; p = 0.006). The results on BC recurrence were of borderline significance. No occupational exposure influenced recurrence or progression. Conclusion: Our results are supported by experimental evidence of a plausible mechanism between cause (ValVal genotype of both MnSOD and COMT) and effect (decreased progression of tumor in NMIBC patients). The genetic polymorphisms associated with better prognosis may be used in clinic to guide selection of treatment for patients initially diagnosed with NMIBC. However, external validation studies are required.

Efficacy and Safety of Blue Light Flexible Cystoscopy with Hexaminolevulinate in the Surveillance of Bladder Cancer: A Phase III, Comparative, Multicenter Study

PURPOSE

We compared blue light flexible cystoscopy with white light flexible cystoscopy for the detection of bladder cancer during surveillance.

MATERIALS AND METHODS

Patients at high risk for recurrence received hexaminolevulinate intravesically before white light flexible cystoscopy and randomization to blue light flexible cystoscopy. All suspicious lesions were documented. Patients with suspicious lesions were referred to the operating room for repeat white and blue light cystoscopy. All suspected lesions were biopsied or resected and specimens were examined by an independent pathology consensus panel. The primary study end point was the proportion of patients with histologically confirmed malignancy detected only with blue light flexible cystoscopy. Additional end points were the false-positive rate, carcinoma in situ detection and additional tumors detected only with blue light cystoscopy.

RESULTS

Following surveillance 103 of the 304 patients were referred, including 63 with confirmed malignancy, of whom 26 had carcinoma in situ. In 13 of the 63 patients (20.6%, 95% CI 11.5-32.7) recurrence was seen only with blue light flexible cystoscopy (p <0.0001). Five of these cases were confirmed as carcinoma in situ. Operating room examination confirmed carcinoma in situ in 26 of 63 patients (41%), which was detected only with blue light cystoscopy in 9 of the 26 (34.6%, 95% CI 17.2-55.7, p <0.0001). Blue light cystoscopy identified additional malignant lesions in 29 of the 63 patients (46%). The false-positive rate was 9.1% for white and blue light cystoscopy. None of the 12 adverse events during surveillance were serious.

CONCLUSIONS

Office based blue light flexible cystoscopy significantly improves the detection of patients with recurrent bladder cancer and it is safe when used for surveillance. Blue light cystoscopy in the operating room significantly improves the detection of carcinoma in situ and detects lesions that are missed with white light cystoscopy.

Oncologic Procedures Amenable to Fluorescence-guided Surgery

OBJECTIVE

Although fluorescence imaging is being applied to a wide range of cancers, it remains unclear which disease populations will benefit greatest. Therefore, we review the potential of this technology to improve outcomes in surgical oncology with attention to the various surgical procedures while exploring trial endpoints that may be optimal for each tumor type.

BACKGROUND

For many tumors, primary treatment is surgical resection with negative margins, which corresponds to improved survival and a reduction in subsequent adjuvant therapies. Despite unfavorable effect on patient outcomes, margin positivity rate has not changed significantly over the years. Thus, patients often experience high rates of re-excision, radical resections, and overtreatment. However, fluorescence-guided surgery (FGS) has brought forth new light by allowing detection of subclinical disease not readily visible with the naked eye.

METHODS

We performed a systematic review of clinicatrials.gov using search terms "fluorescence," "image-guided surgery," and "near-infrared imaging" to identify trials utilizing FGS for those received on or before May 2016.

INCLUSION CRITERIA

fluorescence surgery for tumor debulking, wide local excision, whole-organ resection, and peritoneal metastases.

EXCLUSION CRITERIA

fluorescence in situ hybridization, fluorescence imaging for lymph node mapping, nonmalignant lesions, nonsurgical purposes, or image guidance without fluorescence.

RESULTS

Initial search produced 844 entries, which was narrowed down to 68 trials. Review of literature and clinical trials identified 3 primary resection methods for utilizing FGS: (1) debulking, (2) wide local excision, and (3) whole organ excision.

CONCLUSIONS

The use of FGS as a surgical guide enhancement has the potential to improve survival and quality of life outcomes for patients. And, as the number of clinical trials rise each year, it is apparent that FGS has great potential for a broad range of clinical applications.

Preoperative prediction of muscular invasiveness of bladder cancer with radiomic features on conventional MRI and its high-order derivative maps

PURPOSE

To determine radiomic features which are capable of reflecting muscular invasiveness of bladder cancer (BC) and propose a non-invasive strategy for the differentiation of muscular invasiveness preoperatively.

METHODS

Sixty-eight patients with clinicopathologically confirmed BC were included in this retrospective study. A total of 118 cancerous volumes of interest (VOI) were segmented from patients' T2 weighted MR images (T2WI), including 34 non-muscle invasive bladder carcinomas (NMIBCs, stage <T2) and 84 muscle invasive ones (MIBCs, stage ≥T2). The radiomic features quantifying tumor signal intensity and textures were extracted from each VOI and its high-order derivative maps to characterize heterogeneity of tumor tissues. Statistical analysis was used to build radiomic signatures with significant inter-group differences of NMIBCs and MIBCs. The synthetic minority oversampling technique (SMOTE) and a support vector machine (SVM)-based feature selection and classification strategy were proposed to first rebalance the imbalanced sample size and then further select the most predictive and compact signature subset to verify its differentiation capability.

RESULTS

From each tumor VOI, a total of 63 radiomic features were derived and 30 of them showed significant inter-group differences (P ≤ 0.01). By using the SVM-based feature selection algorithm with rebalanced samples, an optimal subset including 13 radiomic signatures was determined. The area under receiver operating characteristic curve and Youden index were improved to 0.8610 and 0.7192, respectively.

CONCLUSION

3D radiomic signatures derived from T2WI and its high-order derivative maps could reflect muscular invasiveness of bladder cancer, and the proposed strategy can be used to facilitate the preoperative prediction of muscular invasiveness in patients with bladder cancer.

Narrow band imaging-assisted transurethral resection reduces the recurrence risk of non-muscle invasive bladder cancer: A systematic review and meta-analysis

CONTEXT

Compared with white light imaging (WLI) cystoscopy, narrow band imaging (NBI) cystoscopy could increase the visualization and detection of bladder cancer (BC) at the time of transurethral resection (TUR). NBI cystoscopy could increase the detection of BC, but it remains unclear whether narrow band imaging-assisted transurethral resection (NBI-TUR) could reduce the recurrence risk of non-muscle invasive bladder cancer (NMIBC). Several randomized clinical trials (RCTs) have recently tested the efficacy of NBI-TUR for NMIBC.

OBJECTIVE

To perform a systematic review and meta-analysis of RCTs and evaluate the efficacy of NBI-TUR for NMIBC compared with white light imaging-assisted transurethral resection (WLI-TUR). The end point was recurrence risk.

EVIDENCE ACQUISITION

A systematic review of PubMed, Medline, Ovid, Embase, Cochrane and Web of Science was performed in February 2016 and updated in July 2016.

EVIDENCE SYNTHESIS

Overall, six (n = 1084) of 278 trials were included. Three trials performed narrow band imaging-assisted electro-transurethral resection (NBI-ETUR), and two trials performed narrow band imaging-associated bipolar plasma vaporization (NBI-BPV). The last trial performed narrow band imaging-associated holmium laser resection (NBI-HLR). Statistical analysis was performed using Review Manager software (RevMan v.5.3; The Nordic Cochrane Center, Copenhagen, Denmark). The recurrence risk was compared by calculating risk ratios (RRs) with 95% confidence interval (CIs). Risk ratios with 95% CIs were calculated to compare 3-mo, 1-yr, and 2-yr survival rates. NBI-TUR was associated with improvements in the 3-mo recurrence risk (RR: 0.39; 95% CI, 0.26-0.60; p < 0.0001), 1-yr recurrence risk (RR: 0.52; 95% CI, 0.40-0.67; p < 0.00001) and 2-yr recurrence risk (RR: 0.60; 95% CI, 0.42-0.85; p = 0.004) compared with WLI-TUR.

CONCLUSIONS

Compared with WLI-TUR, NBI-TUR can reduce the recurrence risk of NMIBC. The results of this review will facilitate the appropriate application of NBI in NMIBC.

Three-dimensional texture features from intensity and high-order derivative maps for the discrimination between bladder tumors and wall tissues via MRI

PURPOSE

This study aims to determine the three-dimensional (3D) texture features extracted from intensity and high-order derivative maps that could reflect textural differences between bladder tumors and wall tissues, and propose a noninvasive, image-based strategy for bladder tumor differentiation preoperatively.

METHODS

A total of 62 cancerous and 62 wall volumes of interest (VOI) were extracted from T2-weighted MRI datasets of 62 patients with pathologically confirmed bladder cancer. To better reflect heterogeneous distribution of tumor tissues, 3D high-order derivative maps (the gradient and curvature maps) were calculated from each VOI. Then 3D Haralick features based on intensity and high-order derivative maps and Tamura features based on intensity maps were extracted from each VOI. Statistical analysis and recursive feature elimination-based support vector machine classifier (RFE-SVM) was proposed to first select the features with significant differences and then obtain a more predictive and compact feature subset to verify its differentiation performance.

RESULTS

From each VOI, a total of 58 texture features were derived. Among them, 37 features showed significant inter-class differences ([Formula: see text]). With 29 optimal features selected by RFE-SVM, the classification results namely the sensitivity, specificity, accuracy and area under the curve (AUC) of the receiver operating characteristics were 0.9032, 0.8548, 0.8790 and 0.9045, respectively. By using synthetic minority oversampling technique to augment the sample number of each group to 200, the sensitivity, specificity, accuracy an AUC value of the feature selection-based classification were improved to 0.8967, 0.8780, 0.8874 and 0.9416, respectively.

CONCLUSIONS

Our results suggest that 3D texture features derived from intensity and high-order derivative maps can better reflect heterogeneous distribution of cancerous tissues. Texture features optimally selected together with sample augmentation could improve the performance on differentiating bladder carcinomas from wall tissues, suggesting a potential way for tumor noninvasive staging of bladder cancer preoperatively.

[Narrow band imaging-assisted cystoscopy in bladder tumor follow-up: Can more tumors be identified?]

BACKGROUND

Narrow band imaging (NBI) is a new technique of urethrocystoscopy, in which only certain wavelengths [415 (blue) and 540 nm (green)] are used to detect urothelial carcinoma. The aim of the investigation was to analyze the potential benefit of NBI in the follow-up of patients with transitional cell carcinoma of the bladder.

METHODS

Between August 2013 and July 2014, patients with a history of transitional cell carcinoma of the bladder, presenting for follow-up cystoscopy, were either examined via flexible white light endoscopy (WLE) plus second look WLE (n = 251, controls) or second look NBI cystoscopy alone (n = 251) in the same session.

RESULTS

Rates of recurrences were similar in the two groups [NBI 68 (27.1 %); WLE 70 (27.9 %)]. NBI after WLE identified more tumors in 13 patients (5.69 vs. 3.92). In 8 patients NBI showed no vascularization in suspicious areas. In the control arm, in 8 cases more tumors (3.75 vs. 3.13) were identified in the second WLE.

CONCLUSIONS

The additional use of NBI in the follow-up cystoscopy of patients after transurethral resection of nonmuscle invasive bladder cancer leads to an increased number of detected tumors; however, a part of the additionally detected tumors can be explained by the double examination. NBI appears to provide information in individual cases whether transurethral resection of bladder tumor is necessary.

Long-term Bladder and Upper Urinary Tract Follow-up Recurrence and Progression Rates of G1-2 Non-muscle-invasive Urothelial Carcinoma of the Bladder

OBJECTIVE

To evaluate the risk of long-term tumor recurrence and progression in patients with low- and intermediate-risk non-muscle-invasive bladder cancers, which could facilitate optimization in the follow-up schedules.

MATERIALS AND METHODS

A single-institution, retrospective analysis of 704 patients with primary TaG1, TaG2, T1G1, and T1G2 urothelial carcinomas of the bladder without concomitant carcinoma in situ, treated with transurethral resection, was performed. Response was determined and monitored by routine periodic urine cytology, cystoscopy, and upper tract imaging.

RESULTS

The median follow-up was 64.9 months (maximum, 120 months). Among all of the tumors, 59.3% did not relapse, 36.6% recurred in the bladder during the first 5 years of surveillance, and only 3.6% recurred after 5 years of follow-up. Eight urothelial bladder cancers (1.1%) progressed in stage, and 87.5% of the progressions occurred during the first 5 years of surveillance. An upper urinary tract recurrence was detected in 2.4% of the patients; 94.1% were diagnosed within the upper urinary tract during the first 5 years of follow-up and 5.9% occurred after 5 years of surveillance.

CONCLUSION

G1-2 urothelial bladder cancers recur and progress uncommonly in the long-term period. Although limited by its retrospective nature, the present study provides potential grounds for re-examination of the follow-up schedule for patients with primary non-muscle-invasive bladder cancer G1-2 tumors who remain asymptomatic and disease-free for at least 5 years.

Preoperative neutrophil-lymphocyte ratio and fibrinogen level in patients distinguish between muscle-invasive bladder cancer and non-muscle-invasive bladder cancer

INTRODUCTION

The aim of this study was to explore if the preoperative neutrophil-lymphocyte ratio (NLR) and fibrinogen level can help in distinguishing between muscle-invasive bladder cancer (MIBC) and non-muscle-invasive bladder cancer (NMIBC).

METHODS

We identified 669 patients who underwent surgery at our institution, and evaluated their preoperative NLRs and fibrinogen levels. Patients were divided into two groups, NMIBC (group-I) and MIBC (group-II), according to the postoperative pathology. For the intergroup comparison, data obtained from the two groups were evaluated using independent samples t-test. The cutoff value of the NLR, fibrinogen level, and integrated NLR and fibrinogen level was determined with receiver operating characteristic (ROC) curve.

RESULTS

The mean NLRs of group-I and group-II were found as 2.71±2.46 and 4.66±8.00, respectively (P<0.001). The fibrinogen levels of the two groups were ~3.13±0.70 g/L and 3.41±0.84 g/L, respectively (P=0.001). Whether the NLR, fibrinogen level, and integrated NLR and fibrinogen level can help in distinguishing between MIBC and NMIBC was evaluated with ROC curve. The cutoff value of NLR was estimated as 2.01 according to the Youden index. With this value, sensitivity was found as 67.1%, specificity was 52.7%, and area under receiver operating characteristic (ROC) curve (AUC) was 0.601 (P=0.031). The cutoff value of fibrinogen level was estimated as 3.17 g/L according to the Youden index. Accordingly, sensitivity was found as 58%, specificity was 58%, and AUC was 0.60 (P=0.001). The cutoff value of integrated NLR and fibrinogen level was found as 0.166; the sensitivity was found as 86%, specificity was 42%, and AUC was 0.801 (P=0.01).

CONCLUSION

The data obtained in this study suggested that 67.1% of Ta-T1 tumors were likely to be invasive if the NLR was >2.01 and 58% were likely to be invasive if the fibrinogen level was >3.17 g/L. When we used both the NLR and fibrinogen level to distinguish between the MIBC and NMIBC, sensitivity was found to be 86%, and specificity was 42%.

Is it possible to stop follow-up of patients with primary T1G3 urothelial carcinoma of the bladder managed with intravesical bacille Calmette-Guérin immunotherapy?

BACKGROUND

Recurrence and progression of T1 grade 3 (T1G3) urothelial bladder carcinomas (UBCs) treated with bacille Calmette-Guérin (BCG) are common events, but the long-term follow-up of the disease remains controversial.

OBJECTIVE

To evaluate the long-term outcomes of BCG intravesical therapy in relation to disease recurrence and progression in primary T1G3 UBCs and upper tract disease.

PATIENTS AND METHODS

A single-institution, retrospective, population-based analysis of 316 patients with primary T1G3 UBC treated with transurethral resection (TUR) and BCG induction intravesical instillations was performed. Response was determined and monitored by routine periodic urine cytology, cystoscopy, and upper tract imaging.

RESULTS

The median follow-up was 70 months (maximum 210 months). Among all of the tumours, 49.4 % did not relapse, 48.7 % recurred in the bladder during the first 5 years of surveillance, and only 6 patients (1.9 %) recurred after being free of disease during the first 5 years of follow-up. Nineteen percentage of the UBCs progressed to stage T2, and only 2 patients (1.2 %) progressed after the first 5 years of surveillance. An upper urinary tract recurrence was detected in 9.2 % of the patients; 65.5 % were diagnosed within the upper urinary tract during the first 5 years of follow-up.

CONCLUSIONS

Following a 5-year tumour-free period, there is minimal risk of recurrence and progression in T1G3 UBCs treated with TUR and BCG induction intravesical instillations. This finding supports a less intensive and potentially less invasive surveillance scheme of bladder follow-up and upper urinary tract imaging in patients without any recurrence.

The importance of second-look transurethral resection for superficial bladder cancer

Objectives:

The objective of this article is to evaluate the importance of a second-look transurethral resection of bladder tumour (TURBT) in patients with newly diagnosed superficial bladder cancer and its impact on subsequent treatment plan.

Methods:

We carried out a prospective study on 100 consecutive patients with newly diagnosed superficial bladder cancer in whom a second-look TURBT was performed two to six weeks after initial resection. We assessed the incidence of residual tumours, sufficiency of initial pathological staging and grading. We also assessed the need for re-staging and grading after the second-look TURBT.

Results:

Forty-five out of 75 patients (60%) who underwent second-look TURBT had no tumours, 18 (24%) had visible residual tumours and 12 (16%) had microscopic residual tumours. Of the 30 (40%) patients with residual tumours, five had pTa, three had carcinoma in situ (CIS), 12 had pT1, and 10 had pT2 disease. Upstaging and change of treatment plan as a result of the second-look TURBT were necessary in 18/75 (24%) cases, of which 10 cases (13%) underwent radical cystectomy for muscle-invasive tumours.

Conclusions:

A second cystoscopy with or without TURBT is recommended two to six weeks after initial resection of stage Ta and T1 bladder tumours in patients with high-grade transitional carcinoma of the bladder or in patients with multiple tumours. Second-look cystoscopy in this category of patients may reveal the need for early change of treatment plan in about 25% of patients.

High-risk nonmuscle invasive bladder cancer

Please also verify that the expansion of HGT1 is OK as set: The risk of progression for high-grade T1 (HGT1) cancer has been recently established at 21% using updated information on large series and a meta-analysis. These outcomes are better than those classically expected supporting the rule of thirds for HGT1. The main limitation of this subgroup is that most studies are retrospective observational studies, which, compared with randomized controlled trials, are subject to various selection biases, carrying a higher risk of uncontrolled confounding factors, with potential preferential reporting of positive findings.

[Non-muscle-invasive high-grade bladder cancer]

BACKGROUND

Non-muscle-invasive bladder cancer with a low-grade differentiation represents a special challenge.

METHOD

Although urine cytology is still the most reliable and effective urine-based marker and there are no substantial novel aspects in this field, photodynamic diagnostics have the most important value in transurethral resection of the bladder (TURB) of high-grade T1 tumors and new techniques, such as hybrid knife TURB are coming up. The histopathological assessment of T1 tumors can be supplemented by a description of the exact penetration depth, so-called substaging and the invasion pattern.

RESULTS

Intravesicle therapy with Bacillus Calmette-Guèrin (BCG) represents the gold standard and a pillar of bladder-preserving therapy and should be planned as maintenance therapy for at least 1 year. With the right risk constellation cystectomy is a safe and proven concept for high-grade bladder cancer, even without proof of muscle invasion.

A preoperative marker panel for the prediction of residual tumor and the decision making for repeat transurethral resection

OBJECTIVE

To assess the ability of a combined preoperative marker panel to identify patients with residual non-muscle-invasive bladder cancer who might benefit from repeat transurethral resection (reTUR).

METHODS

Ki67, p53, vascular endothelial growth factor-C, E-cadherin, and survivin expressions were evaluated by immunohistochemical staining of surgical specimens from 72 patients who underwent reTUR. Related clinical and molecular markers were analyzed by univariate analyses to develop a marker panel. The predictive value of the marker panel was calculated by receiver operating characteristic curves.

RESULTS

Univariate analyses identified tumor size, number of tumors, p53 expression, E-cadherin expression, and the number of altered markers as risk factors for residual tumor (P = 0.03, 0.05, 0.06, 0.024, and 0.005, respectively). After adjusting for the effects of tumor stage and grade, multivariate analyses identified the number of altered markers as a risk factor for residual tumor (P = 0.004). The addition of tumor size, E-cadherin, and the number of altered markers to the base model (based on tumor stage and tumor grade) increased its discrimination for predicting residual tumor (5%, 6%, and 10%, respectively).

CONCLUSION

Some clinical and molecular markers could improve the accuracy of residual tumor prediction at reTUR. Such a marker panel may help to identify patients with non-muscle-invasive bladder cancer who have residual tumor after first TUR and who may therefore benefit from reTUR.

Reexamining treatment of high-grade T1 bladder cancer according to depth of lamina propria invasion: a prospective trial of 200 patients

BACKGROUND

Management of high-grade T1 (HGT1) bladder cancer represents a major challenge. We studied a treatment strategy according to substaging by depth of lamina propria invasion.

METHODS

In this prospective observational cohort study, patients received initial transurethral resection (TUR), mitomycin-C, and BCG. Subjects with shallower lamina propria invasion (HGT1a) were followed without further surgery, whereas subjects with HGT1b received a second TUR. Association of clinical and histological features with outcomes (primary: progression; secondary: recurrence and cancer-specific survival) was assessed using Cox regression.

RESULTS

Median age was 71 years; 89.5% were males, with 89 (44.5%) cases T1a and 111 (55.5%) T1b. At median follow-up of 71 months, disease progression was observed in 31 (15.5%) and in univariate analysis, substaging, carcinoma in situ, tumour size, and tumour pattern predicted progression. On multivariate analysis only substaging, associated carcinoma in situ, and tumour size remained significant for progression.

CONCLUSIONS

In HGT1 bladder cancer, the strategy of performing a second TUR only in T1b cases results in a global low progression rate of 15.5%. Tumours deeply invading the lamina propria (HGT1b) showed a three-fold increase in risk of progression. Substaging should be routinely evaluated, with HGT1b cases being thoroughly evaluated for cystectomy. Inclusion in the TNM system should also be carefully considered.

Treatment and management of high-grade T1 bladder cancer: what should we do after second TUR?

Most T1 bladder cancers are high grade and have the potential to progress to muscle invasion and extravesical dissemination. Many studies reported that ∼50% of patients displayed residual tumors when a second transurethral resection was performed 2-6 weeks after the initial resection for patients who were diagnosed with T1 bladder cancer. Furthermore, muscle-invasive disease was detected by the second transurethral resection in 10-25% of those patients. Therefore, a second transurethral resection is strongly recommended for patients newly diagnosed with high-grade T1 bladder cancer in various guidelines. T1 bladder cancers are heterogeneous in terms of progression and prognosis after the second transurethral resection. Optimal management and treatment should be considered for patients with T1 bladder cancer based on the pathological findings for the second transurethral resection specimen. If the second transurethral resection reveals residual tumors, aggressive treatments based on the pathological findings should be performed. Conversely, overtreatment with respect to the tumor status should be avoided. Since the evidence of pathological diagnosis at the second transurethral resection is insufficient and many retrospective studies were carried out before the second transurethral resection era, prospective randomized studies should be conducted.

T-helper 1 immunoreaction influences survival in muscle-invasive bladder cancer: proof of concept

Objective

To define immunoscore in bladder cancer studying T helper 1 (Th1) immunoreaction. To define a cancer-specific survival model based on Th1 cells infiltration.

Methods

A total of 252 patients underwent primary transurethral resection of bladder tumour at our Institution. A retrospective review of a selected cohort with pT1 and muscle-invasive bladder cancer (MIBC) lesions was performed. Pathology blocks were marked with CD3 and CD8 antibodies. Immune cells density in stromal reaction (SR) was measured on five distinct high-power field (HPF) by two dedicated uro-pathologist blinded for patients’ evolution.

Statistics

Student test or non-parametric Wilcoxon test as appropriate to compare means between two groups. Receiver operating characteristics (ROC) curve to define markers threshold. Cox model to assess survival’s predictors.

Results

Ten pT1 and 20 MIBC consecutive cases were analysed. Median follow-up was 33.4 months. Immunohistological analysis for pT1 lesions featured limited SR. For MIBC, the mean density of lymphocytes in the SR was of 105/HPF (CD3) and 86/HPF (CD8). Survivors harboured higher lymphocytes densities versus non survivors (CD3: p = 0.0319; CD8: p = 0.0279). CD3 (p = 0.034) and CD8 (p = 0.034) lymphocytes densities were independently associated with cancer-specific survival on Cox model analyses. The retrospective design and small size of cohorts are the study limitations.

Conclusions

High CD3 and CD8 lymphocytes SR densities are associated with better cancer-specific survival for MIBC. Th1 reaction against the tumour seems to be protective for bladder cancer. Further evaluation is warranted.

Analysis of results of recurrence and progression rates of high-grade Ta bladder cancer and comparison with results of high-grade T1

INTRODUCTION

We aimed to evaluate the long-term recurrence and progression rates in a Turkish population with high-grade Ta and T1 bladder cancer and to determine malign potential of high-grade Ta bladder cancer.

METHODS

191 patients who had non-invasive bladder cancer were evaluated at a single institution between 2005 and 2010. Median follow-up was 55.6 months (13-108). Long-term follow-up results of recurrence and progression rates of high-grade Ta and T1 were analyzed and compared with each other.

RESULTS

Of the 191 patients, 143 (74.9%) were high-grade T1 and 48 (25.1%) were high-grade Ta. Of the 143 patients who were high-grade T1, 39 (27.2%) responded to the induction BCG without recurrence. 33 (23%) patients had invasion deep into the muscle layer. 61 (42%) patients had recurred as high-grade T1. Of the 48 patients who were high-grade Ta, 15 (31%) responded to induction BCG without recurrence. 18 (37.5%) patients had recurrence as high-grade Ta. 12 (25%) patients had invasion deep into to the muscle layer. Of all the patients, 13 (7%) patients died of causes related to bladder cancer. In a multivariate analysis, concomitant CIS was statistically significant for the progression of high-grade Ta bladder cancer (p&lt;0.005).

CONCLUSIONS

According to the data of the current study, the presence of concomitant CIS in patients with high-grade bladder cancers is associated with a higher risk of progression. There is a need for larger scale multi-institutional studies in order to support the hypothesis that high-grade Ta tumors should be considered as T1 tumors.

Superficial bladder cancer: part 2. Management

In the second section of a two-part article, the recent literature is reviewed and the management of nonmuscle-invasive transitional cell carcinoma of the bladder is discussed. Particular attention is given to the indications and timing of intravesical chemotherapy and immunotherapy and the differences in efficacy and side-effect profiles of the available agents. The indications and role of second-look transurethral resection are reviewed. Additionally, the role of bacillus Calmette-Guerin in the management of this disease in terms of definitive treatment and maintenance therapy is discussed. We also offer a review of the literature regarding therapies for bacillus Calmette-Guerin-refractory nonmuscle-invasive transitional cell carcinoma of the bladder and their current place in practice.

Recent advances in the treatment of bladder cancer

Bladder cancer continues to provide urologists and researchers with a clinical and scientific challenge. Several urinary markers used in the detection and screening of patients with bladder cancer are currently under investigation. Improvements in intravesical therapy are proving to help decrease both tumor recurrence and progression in patients with high-risk disease. In patients with organ-confined, node-negative bladder cancer, radical cystectomy provides excellent local control and long-term disease-free survival. The use of an extended lymphadenectomy at the time of cystectomy may yield improved prognostic information as well as a potential survival benefit. Neoadjuvant chemotherapy and less toxic combination chemotherapy regimens are offering potential improvements in patients with extravesical or nodal extension. The current methods of detection, as well as available therapeutic treatment options are reviewed.

Importance of the Neutrophil-to-Lymphocyte Ratio in Muscle-Invasive and Non-Muscle Invasive Bladder Tumors

Introduction

To research the importance of the neutrophil-to-lymphocyte ratio (NLR) in muscle-invasive bladder cancers (MIBC) and non-muscle invasive bladder cancer (NMIBC).

Methods

Data of 198 patients who underwent TUR-TM in our clinic were retrospectively evaluated. Patients were divided into two groups: group-I (MIBC) and group-II (NMIBC). The neutrophil and lymphocyte counts, NLR, hemoglobin and hematocrit values, tumor numbers, sizes and degrees of patients were recorded. Within the inter-group comparison, Mann-Whitney U test was used for the values stated with measuring, whereas a Chi-square test was used for the values stated with counting. The cut-off value for the NLR was determined with ROC curve.

Results

The NLR values of group-I and group-II were found as 4.14 ± 2.76 and 3.36 ± 2.88, respectively (p = 0.03). Whether the NLR carries a differential property was evaluated with ROC curve. The cut-off value was estimated as 3.96 according to the Youden index. With this value, sensitivity was found as 50%, specificity was 22.8% and AUC was 0.615 (p = 0.03).

Discussion

According to the data in this study, it can be said that Ta-T1 tumors are likely to be invasive by 50% if the NLR value is greater than 3.96.

Photodynamic diagnosis of non-muscle-invasive bladder cancer with hexaminolevulinate cystoscopy: a meta-analysis of detection and recurrence based on raw data

BACKGROUND

Studies on hexaminolevulinate (HAL) cystoscopy report improved detection of bladder tumours. However, recent meta-analyses report conflicting effects on recurrence.

OBJECTIVE

To assess available clinical data for blue light (BL) HAL cystoscopy on the detection of Ta/T1 and carcinoma in situ (CIS) tumours, and on tumour recurrence.

DESIGN, SETTING, AND PARTICIPANTS

This meta-analysis reviewed raw data from prospective studies on 1345 patients with known or suspected non-muscle-invasive bladder cancer (NMIBC).

INTERVENTION

A single application of HAL cystoscopy was used as an adjunct to white light (WL) cystoscopy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We studied the detection of NMIBC (intention to treat [ITT]: n=831; six studies) and recurrence (per protocol: n=634; three studies) up to 1 yr. DerSimonian and Laird's random-effects model was used to obtain pooled relative risks (RRs) and associated 95% confidence intervals (CIs) for outcomes for detection.

RESULTS AND LIMITATIONS

BL cystoscopy detected significantly more Ta tumours (14.7%; p<0.001; odds ratio [OR]: 4.898; 95% CI, 1.937-12.390) and CIS lesions (40.8%; p<0.001; OR: 12.372; 95% CI, 6.343-24.133) than WL. There were 24.9% patients with at least one additional Ta/T1 tumour seen with BL (p<0.001), significant also in patients with primary (20.7%; p<0.001) and recurrent cancer (27.7%; p<0.001), and in patients at high risk (27.0%; p<0.001) and intermediate risk (35.7%; p=0.004). In 26.7% of patients, CIS was detected only by BL (p<0.001) and was also significant in patients with primary (28.0%; p<0.001) and recurrent cancer (25.0%; p<0.001). Recurrence rates up to 12 mo were significantly lower overall with BL, 34.5% versus 45.4% (p=0.006; RR: 0.761 [0.627-0.924]), and lower in patients with T1 or CIS (p=0.052; RR: 0.696 [0.482-1.003]), Ta (p=0.040; RR: 0.804 [0.653-0.991]), and in high-risk (p=0.050) and low-risk (p=0.029) subgroups. Some subgroups had too few patients to allow statistically meaningful analysis. Heterogeneity was minimised by the statistical analysis method used.

CONCLUSIONS

This meta-analysis confirms that HAL BL cystoscopy significantly improves the detection of bladder tumours leading to a reduction of recurrence at 9-12 mo. The benefit is independent of the level of risk and is evident in patients with Ta, T1, CIS, primary, and recurrent cancer.