Bladder wall thickness in normal adults and men with mild lower urinary tract symptoms and benign prostatic enlargement

Urinary organs-at-risk for prostate cancer external beam radiotherapy: contouring guidelines on behalf of the Francophone Group of Urological Radiation Therapy (GFRU)

PURPOSE

Occurrence of genitourinary (GU) toxicity is a common adverse event observed after external beam radiotherapy (EBRT) for prostate cancer (PCa). Recent findings suggest that the dose delivered to specific urinary organs-at-risk (OARs) such as ureters, bladder trigone, and urethra is involved in the development of GU toxicity.

METHODS AND MATERIALS

A multidisciplinary task force including three radiation oncologists, a uroradiologist, and a urologist was created in 2022. First, OARs potentially involved in GU toxicity were identified and discussed. A literature review was performed, addressing several questions relative to urinary OARs: anatomical and radiological definition, radiation-induced injury, dose-volume parameters. Secondly, results were presented and discussed with a panel of radiation oncologists, members of the "Francophone Group of Urological Radiation Therapy" (GFRU). Thereafter, GFRU experts were asked to answer a dedicated questionnaire, including 35 questions on the controversial issues related to the delineation of urinary OARs.

RESULTS

The following structures were identified as critical for PCa EBRT: ureters, bladder, bladder neck, bladder trigone, urethra (intraprostatic, membranous, spongious), striated sphincter, and post-enucleation or post-transurethral resection of the prostate (TURP) cavity. A consensus was obtained for 32 out of 35 items.

CONCLUSION

This consensus highlights contemporary urinary structures in both upper and lower urinary tract to be considered for EBRT treatment planning of PCa. The current recommendations also propose a standardized definition of urinary OARs, for both daily practice and future clinical trials.

Association of detrusor wall thickness (DWT) with lower urinary tract symptom severity in benign prostatic hyperplasia: a cross-sectional study

Background and objective

Benign prostatic hyperplasia manifests as lower urinary tract symptoms (LUTS) and prostate gland enlargement, leading to bladder outlet obstruction with consequent structural and functional impacts on the bladder. Urodynamic studies are resource-intensive and invasive. Detrusor wall thickness (DWT) assessment offers a cost-effective, reproducible alternative for evaluating LUTS severity in males with bladder outlet obstruction, utilizing ultrasonographic examination.

Methods

This prospective cross-sectional study, conducted at a tertiary care center from May 2023 to January 2024, included 171 patients with LUTS who underwent transabdominal ultrasound for DWT measurements. LUTS severity, assessed using International Prostate Symptom Scores (IPSS) classified participants into mild and moderate-to-severe symptom groups. Pearson's correlation coefficient assessed the association between DWT and IPSS, and an independent sample t-test compared means, using a significance level of 5% (P-value ≤0.05).

Results

This study involved participants aged 65.01±11.55 years with an IPSS score ranging from 1 to 35, with a mean for mild and moderate-to-severe symptom groups were 4±2.12 and 15.93±6.74, respectively. DWT mean of 1.64±0.38 mm for mild, and 2.4±0.43 mm for moderate to severe symptoms. Pearson's correlation (r=0.697, n=171, P<0.001) indicated a strong DWT-LUTS correlation and a significant DWT mean difference between mild and moderate-to-severe symptom groups was found via an independent t-test (P<0.001, 95% CI: -0.8970 to -0.6414).

Conclusion

The study establishes the value of transabdominal ultrasound-detected DWT as a cost-effective, noninvasive, and reproducible tool for assessing LUTS severity in males with benign prostatic hyperplasia.

Clinical impact of detrusor muscle in en bloc resection for T1 bladder cancer

PURPOSE

Detrusor muscle (DM) in the resected specimen of patients with pT1 bladder cancer (BCa) is a quality-of-care criteria. We aimed to assess whether obtaining adequate DM is dependent on surgeon's experience, whether is a surrogate for resection quality, and whether the degree of DM thickness is related to postoperative outcomes in en bloc resection for bladder tumors (ERBT).

MATERIALS AND METHODS

We retrospectively analyzed the records of 106 pT1 high-grade BCa patients who underwent ERBT at several institutions. All specimens were reviewed by a single pathologist who assessed the presence or absence of DM and its thickness measured by a micrometer, when present. Early recurrence, defined as pathologically confirmed BCa on repeat resection or tumor recurrence at the first follow-up cystoscopy (within 3 months), was the endpoint reflective of the resection quality.

RESULTS

Of 106 patients, DM was detected in 99 (93%), and the median DM thickness was 1.8 mm. Large tumor size (>30 mm) was associated with adequate DM sampling (>1.8mm) (odds ratio [OR]: 6.10, 95% confidence intervals [CIs]: 2.08-17.9, P = 0.001), while surgeon's experience was not. DM presence and DM thickness were both not associated with early recurrence, while positive surgical margin was an independent prognosticator for early recurrence (OR: 3.38, 95% CI: 1.12-10.2, P = 0.031). Excessive DM sampling (>2.1 mm) was associated with prolonged urethral catheterization (OR: 28.8, 95% CI: 3.36-248, P = 0.002).

CONCLUSIONS

In ERBT, surgeon's experience seems irrelevant to obtain DM. Resection quality relies on surgical margin status, not the degree of DM. Obtaining excessive DM incurs adverse events/unnecessary medical care.

Correlation between bladder wall thickness and uroflowmetry in West African patients with benign prostatic enlargement

Background

Pressure flow urodynamic study remains the gold standard for the diagnosis of bladder outlet obstruction; however, their use is limited by their relative unavailability in our environment, cost, and invasiveness. Measurement of bladder wall thickness (BWT) by transabdominal ultrasonography is a promising tool that can be used to diagnose bladder outlet obstruction in our environment where pressure-flow urodynamic study is not readily available.

Objective

The study aimed to correlate BWT with uroflowmetry and to establish a BWT cut-off in patients with lower urinary tract symptoms (LUTS) due to benign prostatic enlargement.

Materials and Methods

This was a prospective one-year study of patients with LUTS due to benign prostatic enlargement. The patients were divided into obstructed and non-obstructed groups with Q- max of 10 ml/s serving as the cut-off value. Receiver Operator Curve (ROC) was used to evaluate the performance of BWT in diagnosing BOO. Statistical significance was set at P < 0.05.

Results

The mean BWT and Q-max were 4.53 ± 2.70 mm and 15.06 ± 9.43 ml/s. There was a negative correlation between BWT and Q-max (r = -0.452, P = 0.000), Q-average (r = -0.336, P = 0.000), and voided volume (r = -0.228, P = 0.046). A BWT cut-off of 5.85 mm was found to be the best threshold to differentiate obstructed from non-obstructed patients with a sensitivity and specificity of 70 and 88.2 percent respectively.

Conclusion

Bladder wall thickness showed an inverse relationship with maximum flow rate with high sensitivity and specificity. This non-invasive test can be used as a screening tool for BOO in our setting, where the pressure flow urodynamic study is not readily available.

Photodynamic Therapy for Bladder Cancers, A Focused Review†

Bladder cancer is the first cancer for which PDT was clinically approved in 1993. Unfortunately, it was unsuccessful due to side effects like bladder contraction. Here, we summarized the recent progress of PDT for bladder cancers, focusing on photosensitizers and formulations. General strategies to minimize side effects are intravesical administration of photosensitizers, use of targeting strategies for photosensitizers and better control of light. Non-muscle invasive bladder cancers are more suitable for PDT than muscle invasive and metastatic bladder cancers. In 2010, the FDA approved blue light cystoscopy, using PpIX fluorescence, for photodynamic diagnosis of non-muscle invasive bladder cancer. PpIX produced from HAL was also used in PDT but was not successful due to low therapeutic efficacy. To enhance the efficacy of PpIX-PDT, we have been working on combining it with singlet oxygen-activatable prodrugs. The use of these prodrugs increases the therapeutic efficacy of the PpIX-PDT. It also improves tumor selectivity of the prodrugs due to the preferential formation of PpIX in cancer cells resulting in decreased off-target toxicity. Future challenges include improving prodrugs and light delivery across the bladder barrier to deeper tumor tissue and generating an effective therapeutic response in an In vivo setting without causing collateral damage to bladder function.

The trend of schistosomiasis related bladder cancer in the lake zone, Tanzania: a retrospective review over 10 years period

INTRODUCTION

Bladder cancer is a possible outcome of chronic urinary schistosomiasis in many endemic countries. In Tanzania, the Lake Victoria area is one of the areas with the highest prevalence of urinary schistosomiasis and higher incidences of squamous cell carcinoma (SCC) of the urinary bladder. A previous study in the area over one decade (2001-2010) showed SCC to be common in patients aged below 50 years. With various prevention and intervention programs there are likely to be notable changes in schistosomiasis-related urinary bladder cancer, which is currently unknown. Updated information on the status of SCC in this area will be useful for giving an insights into efficacy of control interventions implemented and help guide the initiation of new ones. Therefore, this study was done to determine the current trend of schistosomiasis-related bladder cancer in lake zone, Tanzania.

METHODS

This was a descriptive retrospective study of histologically confirmed urinary bladder cancer cases diagnosed at the Pathology Department of Bugando Medical Centre over 10 years period. The patient files and histopathology reports were retrieved and information was extracted. Data were analyzed using Chi-square and student t-test.

RESULTS

A total of 481 patients were diagnosed with urinary bladder cancer during the study period whereby, 52.6% were males and 47.4% were females. The mean age regardless of histological type of cancer was 55 ± 14.2 years. The SCC was the commonest histological type accounting for 57.0%, followed by transitional cell carcinoma 37.6%, and 5.4% were adenocarcinomas. The Schistosoma haematobium eggs were observed in 25.2% and were commonly associated with SCC (p = 0.001). Poorly differentiated cancers were observed mostly in females (58.6%) compared to males (41.4%) (p = 0.003). Muscular invasion of the urinary bladder by cancer was observed in 11.4% of the patients, and this was significantly higher in non-squamous than in squamous cancers (p = 0.034).

CONCLUSION

Schistosomiasis-related cancers of the urinary bladder in the Lake zone of Tanzania is still a problem. Schistosoma haematobium eggs were associated with SCC type indicating the persistence of infection in the area. This calls for more efforts on preventive and intervention programs to reduce the burden of urinary bladder cancer in the lake zone.

The bladder contractility and bladder outlet obstruction indices in adult women. Results of a global Delphi consensus study

AIMS

This Delphi study was planned to examine global expert consensus with regard to utility, accuracy, and categorization of the bladder contractility index (BCI), bladder outlet obstruction index (BOOI), and the related evidence. This manuscript deals with adult women and follows a previous manuscript reporting on adult men.

METHODS

Twenty-nine experts were invited to answer the two-round survey including three foundation questions and 12 survey questions. Consensus was defined as ≥75% agreement. The ordinal scale (0-10) in round 1 was classified into "strongly agree," "agree," "neutral," "disagree," and "strongly disagree" for the final round. A systematic search for evidence was conducted for therapeutic studies that have examined outcome stratified by the indices in women.

RESULTS

Eighteen experts participated in the survey with 100% completion. Consensus was noted with regard to 2 of 12 questions, both in the negative. The experts had a consensus that BOOI was neither accurate nor useful and a similar negative trend was noted with regard to BCI. However, there was support, short of consensus, for the utility on an index of bladder contractility and bladder outflow obstruction. Systematic search yielded eight publications pertaining to stress urinary incontinence (n = 6), pelvic organ prolapse (n = 1), and intra-sphincteric botulinum toxin (n = 1).

CONCLUSIONS

Experts had significant concerns with regard to the use of the male BCI and BOOI in adult women despite a general recognition of the need for numerical indices of contractility and obstruction. Systematic search showed a striking lack of evidence in this regard.

The Tabula Sapiens: A multiple-organ, single-cell transcriptomic atlas of humans

Molecular characterization of cell types using single-cell transcriptome sequencing is revolutionizing cell biology and enabling new insights into the physiology of human organs. We created a human reference atlas comprising nearly 500,000 cells from 24 different tissues and organs, many from the same donor. This atlas enabled molecular characterization of more than 400 cell types, their distribution across tissues, and tissue-specific variation in gene expression. Using multiple tissues from a single donor enabled identification of the clonal distribution of T cells between tissues, identification of the tissue-specific mutation rate in B cells, and analysis of the cell cycle state and proliferative potential of shared cell types across tissues. Cell type-specific RNA splicing was discovered and analyzed across tissues within an individual.

Feasibility of a deep learning-based diagnostic platform to evaluate lower urinary tract disorders in men using simple uroflowmetry

Purpose

To diagnose lower urinary tract symptoms (LUTS) in a noninvasive manner, we created a prediction model for bladder outlet obstruction (BOO) and detrusor underactivity (DUA) using simple uroflowmetry. In this study, we used deep learning to analyze simple uroflowmetry.

Materials and Methods

We performed a retrospective review of 4,835 male patients aged ≥40 years who underwent a urodynamic study at a single center. We excluded patients with a disease or a history of surgery that could affect LUTS. A total of 1,792 patients were included in the study. We extracted a simple uroflowmetry graph automatically using the ABBYY Flexicapture^® image capture program (ABBYY, Moscow, Russia). We applied a convolutional neural network (CNN), a deep learning method to predict DUA and BOO. A 5-fold cross-validation average value of the area under the receiver operating characteristic (AUROC) curve was chosen as an evaluation metric. When it comes to binary classification, this metric provides a richer measure of classification performance. Additionally, we provided the corresponding average precision-recall (PR) curves.

Results

Among the 1,792 patients, 482 (26.90%) had BOO, and 893 (49.83%) had DUA. The average AUROC scores of DUA and BOO, which were measured using 5-fold cross-validation, were 73.30% (mean average precision [mAP]=0.70) and 72.23% (mAP=0.45), respectively.

Conclusions

Our study suggests that it is possible to differentiate DUA from non-DUA and BOO from non-BOO using a simple uroflowmetry graph with a fine-tuned VGG16, which is a well-known CNN model.

Biomaterials assisted reconstructive urology: The pursuit of an implantable bioengineered neo-urinary bladder

Urinary bladder is a dynamic organ performing complex physiological activities. Together with ureters and urethra, it forms the lower urinary tract that facilitates urine collection, low-pressure storage, and volitional voiding. However, pathological disorders are often liable to cause irreversible damage and compromise the normal functionality of the bladder, necessitating surgical intervention for a reconstructive procedure. Non-urinary autologous grafts, primarily derived from gastrointestinal tract, have long been the gold standard in clinics to augment or to replace the diseased bladder tissue. Unfortunately, such treatment strategy is commonly associated with several clinical complications. In absence of an optimal autologous therapy, a biomaterial based bioengineered platform is an attractive prospect revolutionizing the modern urology. Predictably, extensive investigative research has been carried out in pursuit of better urological biomaterials, that overcome the limitations of conventional gastrointestinal graft. Against the above backdrop, this review aims to provide a comprehensive and one-stop update on different biomaterial-based strategies that have been proposed and explored over the past 60 years to restore the dynamic function of the otherwise dysfunctional bladder tissue. Broadly, two unique perspectives of bladder tissue engineering and total alloplastic bladder replacement are critically discussed in terms of their status and progress. While the former is pivoted on scaffold mediated regenerative medicine; in contrast, the latter is directed towards the development of a biostable bladder prosthesis. Together, these routes share a common aspiration of designing and creating a functional equivalent of the bladder wall, albeit, using fundamentally different aspects of biocompatibility and clinical needs. Therefore, an attempt has been made to systematically analyze and summarize the evolution of various classes as well as generations of polymeric biomaterials in urology. Considerable emphasis has been laid on explaining the bioengineering methodologies, pre-clinical and clinical outcomes. Some of the unaddressed challenges, including vascularization, innervation, hollow 3D prototype fabrication and urinary encrustation, have been highlighted that currently delay the successful commercial translation. More importantly, the rapidly evolving and expanding concepts of bioelectronic medicine are discussed to inspire future research efforts towards the further advancement of the field. At the closure, crucial insights are provided to forge the biomaterial assisted reconstruction as a long-term therapeutic strategy in urological practice for patients' care.

Bladder surface dose modeling in prostate cancer radiotherapy: An analysis of motion-induced variations and the cumulative dose across the treatment

PURPOSE

To introduce a novel surface-based dose mapping method to improve quantitative bladder dosimetric assessment in prostate cancer (PC) radiotherapy.

METHODS

Based on the planning and daily pre and postfraction MRIs of 12 PC patients, bladder surface models (SMs) were generated on manually delineated contours and regionally aligned via surface-based registration. Subsequently, bladder surface dose models (SDMs) were created using face-wise dose sampling. To determine the bladder intrafractional and interfractional motion and dose variation, we performed a pose analysis between pre and postfraction bladder SMs, as well as surface mapping for fractional SMs. Discrepancies between the received dose, accumulated from daily SDMs, and the planned dose were then assessed on the corresponding SDMs. Complementary to the surface dose mapping, dose surface histogram (DSH)-based comparisons were also performed.

RESULTS

The intrafraction pose analysis revealed a significant (p < 0.05) bladder expansion, as well as an anterior/superior drift during the treatment. The intrafraction motion substantially altered dose to mid-bladder body, but not the bladder surface areas distal to or contiguous with the target. A similar pattern of dose variations was also detected by interfraction comparisons. With surface registration to the common SM, the cumulative bladder dose significantly differs from the planned dose. The discrepancy is evident in the mid-posterior range that corresponds to a mid- to high-dose region. The received DSH significantly differs from the planned DSH after permutation correction (p = 0.0122), while the overall surface-based comparison after multiple comparison correction is nonsignificant (p = 0.0800).

CONCLUSIONS

We developed a novel surface-based intra and interdose mapping framework applied to a unique daily MR dataset for image-guided radiotherapy. The framework identified significant intrafraction bladder positional changes, localized the intra and interfraction variations, and quantified planned versus received dose differences on the bladder surface. The result indicates the importance of adopting the motion-integrated bladder SDM for bladder dose management.

Evaluation of an ultrasound bladder scanner in supine and standing position

PURPOSE

This study examined the performance of a bladder volume measuring device, the BladderScan (BS) BVI9400. The use of the BS offers the possibility of assessing the bladder volume before positioning the patient and performing the daily image-guided radiotherapy procedure. Patients often cannot lie down before entering the treatment vault. Therefore, the BS was also assessed in a standing position.

METHODS

The repeatability precision was first evaluated, which is the variability of immediate repeated measures of the BS with same operator and subject. This was followed by the reproducibility precision of the BS in which the operator and subjects differ. Finally, the trueness was evaluated in terms of fixed and proportional bias of the results by applying weighted least-squares fitting. Note that 53 and 85 patient measurements were carried out in supine and standing position, respectively, each consisting of three repeated BS measurements. These were compared with the computed tomography (CT)-delineated bladder volume.

RESULTS

Repeatability was dependent on measurement value (heteroscedasticity) with σ_{repeatability} (BS) = ±15 cm³  ± 10%. However, the total agreement between BS and CT was low with the 95% limits of agreement (LOAs) exceeding ±200 cm³ due to poor patient reproducibility and presence of fixed and proportional bias. Only in the best case of male patients in the supine position, three BS measurements, and correction for the fixed and proportional bias, 95% LOAs of [-147, +114] cm³ were obtained between CT and BS.

CONCLUSION

The agreement of the BVI9400 BS with CT was found to be too low for radiotherapy applications.

Correlations between bladder wall thickness and clinical manifestations in female patients with detrusor underactivity and detrusor overactivity-with-detrusor underactivity

BACKGROUND

Among female patients with lower urinary tract symptoms, detrusor underactivity (DU), and detrusor overactivity-with-detrusor underactivity (DO-DU) are two common diagnoses. Here, we investigated the correlations between bladder wall thickness (BWT) and clinical manifestations of the two diagnoses.

METHODS

From 2011 to 2016, female patients with DU or DO-DU, diagnosed at our institute, were recruited. We analyzed their urodynamic parameters and collected three questionnaires (IPSS, UDI-6, OABSS). Using transabdominal sonography, the BWT was recorded. DU was defined as follows: maximum free flow rate (Qmax) ≤ 15 cc/s; detrusor pressure at maximum flow (PdetQmax) ≤ 20 cmH2O; bladder capacity > 150 cc. DO-DU was defined as follows: Qmax ≤ 15 cc/s; PdetQmax ≤ 20 cmH2O; bladder capacity ≤ 150 cc. The BWTs of the two groups were compared using the Mann-Whitney U test; the correlations among the BWTs and the results of three questionnaires were analyzed using Spearman's rank correlation coefficient.

RESULTS

Forty-eight female patients with DU and 13 with DO-DU were recruited. Demographic data revealed no differences between the two groups. The mean BWT of the DO-DU patients was significantly larger than that of the DU patients (4.11 vs 3.42 mm; p = 0.001). In the DO-DU group, a high correlation existed between the BWT and some of the UDI-6 items (urgency incontinence: r = 0.831, p = 0.006; incontinence related to activity: r = 0.884, p = 0.002; small amounts of leakage: r = 0.809, p = 0.008). The BWT of the DO-DU patients also exhibited a moderate correlation with the urgency incontinence from the OABSS questionnaire (r = 0.679; p = 0.044). No correlations existed between the BWT of the DU patients and any of the data from the three questionnaires.

CONCLUSION

The BWT in the DO-DU patients was significantly thicker than that in the DU patients. The DO-DU patients with thicker bladder walls also had higher UDI-6 scores for both urgency and urgency incontinence.

Evaluation of ultrasonographic predictors of alpha-blocker mono-therapy failure in symptomatic benign prostatic enlargement

Objectives:

Many sonographic parameters for predicting treatment failure for benign prostate enlargement have been described. Patients may take alpha-blockers for a long time at high cost before conversion to surgery.

Purpose:

Evaluation of the sonographic parameters that predict alpha 1 adrenoreceptor blocker monotherapy outcomes in symptomatic patients with benign prostate enlargement.

Patients and Methods:

Between June 2016 and July 2019, we prospectively enrolled 750 symptomatic patients with benign prostate enlargement. Trans-rectal ultrasonography was performed, and patients were given Tamsulosin (0.4 mg) oral tablets once daily for 6 months. Treatment outcomes were determined using quality of life, the International Prostatic Symptom Score, and maximum urine flow rate measures. The values of the measured baseline sonographic parameters on treatment outcomes were statistically analyzed.

Results:

Seven-hundred and fifty patients completed the study, and treatment was ineffective in 225 of them (30%). From the measured prostate and bladder sonographic parameters, intra-vesical prostate growth was only significant. Using a cutoff value of 8.2 mm, the area under the receiver operator characteristic curve for intra-vesical prostatic protrusion was 0.866. Using this cutoff value (with 95% confidence interval), both positive and negative predictive values were 73.3% and 98.18%, respectively.

Conclusion:

Based on sonographic parameters, only the intravesical prostate protrusion was valid for predicting alpha-blocker monotherapy failure in symptomatic benign prostate enlargement patients. This information helps determine a medical therapeutic plan and the need for surgical intervention.

Comprehensive non-invasive analysis of lower urinary tract anatomy using MRI

PURPOSE

Anatomic changes that coincide with aging including benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS) negatively impact quality of life. Use of MRI with its exquisite soft tissue contrast, full field-of-view capabilities, and lack of radiation is uniquely suited for quantifying specific lower urinary tract features and providing comprehensive measurements such as total bladder wall volume (BWV), bladder wall thickness (BWT), and prostate volume (PV). We present a technique for generating 3D anatomical renderings from MRI to perform quantitative analysis of lower urinary tract anatomy.

METHODS

T2-weighted fast-spin echo MRI of the pelvis in 117 subjects (59F;58 M) aged 30-69 (49.5 ± 11.3) without known lower urinary tract symptoms was retrospectively segmented using Materialise software. Virtual 3D models were used to measure BWV, BWT, and PV.

RESULTS

BWV increased significantly between the 30-39 and 60-69 year age group in women (p = 0.01), but not men (p = 0.32). BWV was higher in men than women aged 30-39 and 40-49 (p = 0.02, 0.05, respectively) ,but not 50-59 or 60-69 (p = 0.18, 0.16, respectively). BWT was thicker in men than women across all age groups. Regional differences in BWT were observed both between men and women and between opposing bladder wall halves (anterior/posterior, dome/base, left/right) within each sex in the 50-59 and 60-69 year groups. PV increased from the 30-39 to 60-69 year groups (p = 0.05). BWT was higher in subjects with enlarged prostates (> 40cm³) (p = 0.05).

CONCLUSION

Virtual 3D MRI models of the lower urinary tract reliably quantify sex-specific and age-associated changes of the bladder wall and prostate.

Does Body Position Affect Ultrasound Measurements of Bladder-Wall Elasticity?

Ultrasound bladder vibrometry (UBV) parameters have been shown in previous studies to strongly correlate with measurements from urodynamic studies. Just like urodynamic studies, UBV can be performed in supine and sitting positions. The objective of this study is to compare UBV parameters obtained in the two different positions using statistical methods. We recruited eight volunteers with healthy bladders for this purpose. The elasticity, group velocity squared and thickness of the bladder were the UBV parameters of interest, and their values were recorded at different bladder volumes for each volunteer. The results presented indicate that the measurements made in the two positions are in agreement using the Bland-Altman method and a parameter q which compares the values at each bladder volume for each volunteer. UBV parameters were also repeatable for measurements recorded in the supine and sitting positions.

Normal tissue complication probability (NTCP) models of acute urinary toxicity (AUT) following carbon ion radiotherapy (CIRT) for prostate cancer

PURPOSE

To estimate the Lyman Kutcher Burman (LKB) and multivariate NTCP models predicting the AUT of prostate cancer treated with CIRT.

MATERIALS AND METHODS

A cohort of 154 prostate adenocarcinoma patients were retrospectively analyzed. The AUT levels were graded according to CTCAE 4.03. Based on dosimetric parameters and/or clinical factors, a set of variables with best-fit values determined in the two models was validated by the area under the receiver operating characteristic curve (AUC) and used to correlate the predicted and observed NTCP rates for both levels and related endpoints.

RESULT

59 (38.3%) patients experienced AUT. For LKB model, the equivalent uniform doses (EUDs) were calculated to be 62.0 GyE (following V_61.5 > 1.7%) and 61.2 GyE (following maximum dose > 63.0 GyE) with predicted NTCP rates of 37.0% (AUC: 0.71) and 15.6% (AUC: 0.65) for AUT G1&2 and G2 of bladder. While for the multivariate model, the predicted NTCP rates was 37.1% (AUC: 0.70) and 20.2% (AUC: 0.64) for AUT G1&2 and G2, associated with V₆₁ and V₆₅, respectively. Nocturia was associated with bladder volume and maximum dose for G1&2, with patient's age and maximum bladder dose for G2. Other predictable endpoints were associated with V_≥61. The predicted NTCPs agree with the observed complication rates for bladder and its wall.

CONCLUSIONS

The LKB model successfully predicted the NTCP rates of both AUT levels and urgency urination. The multivariate model predicted well on both levels and nocturia. Decreasing high bladder dose volume may reduce the incidence of AUT.

Bladder perforation during transurethral resection of bladder tumour is not a result of a deficient structure of the bladder wall

Background

Transurethral resection of the bladder tumour (TUR) is associated with a risk of bladder perforation. The underlying mechanisms and risk factors are not fully understood. The aim of this study was to determine if the bladder wall structure affects the risk of bladder perforation during TUR.

Methods

Fifteen patients who underwent TUR complicated by a bladder perforation (group 1) and fifteen matched controls who underwent uncomplicated TUR (group 2) were retrospectively enrolled in this morphological analysis. Surgical specimens were collected from all participating patients to describe the quality and architecture of urothelium and bladder submucosa. Immunohistochemical studies were performed with primary mouse anti-human E-cadherin, beta-catenin, type IV collagen, cytokeratin 20 and epithelial membrane antigen antibodies. The intensity of the immunohistochemical reaction was assessed using an immunoreactive score (IRS). Ultrastructural examinations were performed by transmission electron microscopy. The microscopic assessment was focused on the intensity of fibrosis in the bladder submucosa and the presence of degenerative changes in the urothelium.

Results

Patients’ age, sex distribution, tumour diameters, surgeon experience or cancer stage did not differ between study groups. The immunohistochemical analysis did not reveal statistically significant differences between group 1 and group 2. From a clinical point of view, ultrastructural analysis by electron microscopy showed a higher rate of severe fibrosis in group 1 (63.6% vs. 38.5%), with no differences in the rate and degree of urothelial changes. However, these differences were not statistically significant (p = 0.32).

Conclusions

Bladder perforation during TUR is not a result of a deficient structure of the bladder wall. Based on available evidence, the surgical technique seems to play the most important role in its prevention.

Fully Automated Segmentation of Bladder Sac and Measurement of Detrusor Wall Thickness from Transabdominal Ultrasound Images

Ultrasound measurements of detrusor muscle thickness have been proposed as a diagnostic biomarker in patients with bladder overactivity and voiding dysfunction. In this study, we present an approach based on deep learning (DL) and dynamic programming (DP) to segment the bladder sac and measure the detrusor muscle thickness from transabdominal 2D B-mode ultrasound images. To assess the performance of our method, we compared the results of automated methods to the manually obtained reference bladder segmentations and wall thickness measurements of 80 images obtained from 11 volunteers. It takes less than a second to segment the bladder from a 2D B-mode image for the DL method. The average Dice index for the bladder segmentation is 0.93 ± 0.04 mm, and the average root-mean-square-error and standard deviation for wall thickness measurement are 0.7 ± 0.2 mm, which is comparable to the manual ground truth. The proposed fully automated and fast method could be a useful tool for segmentation and wall thickness measurement of the bladder from transabdominal B-mode images. The computation speed and accuracy of the proposed method will enable adaptive adjustment of the ultrasound focus point, and continuous assessment of the bladder wall during the filling and voiding process of the bladder.

Mitomycin C-induced cell cycle arrest enhances 5-aminolevulinic acid-based photodynamic therapy for bladder cancer

BACKGROUND

Photodynamic therapy (PDT) and diagnosis (PDD) using 5-aminolevulinic acid (ALA) to control the production of the intracellular photosensitizer protoporphyrin IX (PpIX) are commonly used clinically. Previously, we demonstrated that dormant and drug-induced dormancy-like cancer cells accumulated high PpIX levels, making them sensitive to ALA-PDT. Because EAU Guidelines awarded a level of evidence of 1a to mitomycin C, the drug is widely used to treat bladder cancer. In this study, we investigated that the effect of mitomycin C-induced cell cycle arrest on porphyrin metabolism, including that induced by ALA-PDT.

METHODS

T24 human urinary bladder carcinoma cells were selected for this research. T24 cells were irradiated using a light-emitting diode emitting red light for the ALA-PDT assay. Cell cycle analysis was conducted by flow cytometry using bromodeoxyuridine. Cell viability was confirmed using the MTT or colony formation assay. Furthermore, mRNA gene expression analysis was performed using our previously reported methods.

RESULTS

The cell cycle of T24 cells was arrested at G2/M phase by mitomycin C. PpIX accumulation was dramatically increased by mitomycin C treatment. Cell viability after ALA-PDT was remarkably decreased by mitomycin C pretreatment. The gene expression of porphyrin transporters was consistent with the metabolic and morphological results. Finally, we confirmed that ALA-PDT combined with mitomycin C treatment exerted a long-term inhibitory effect on cell proliferation.

CONCLUSION

This study demonstrated a new approach to enhance the effects of ALA-PDT using drugs that induce a dormancy-like status and upregulate porphyrin metabolism.

Minimal required PDT light dosimetry for nonmuscle invasive bladder cancer

SIGNIFICANCE

Photodynamic therapy (PDT) could become a treatment option for nonmuscle invasive bladder cancer when the current high morbidity rate associated with red light PDT and variable PDT dose can be overcome through a combination of intravesical instillation of the photosensitizer and the use of green light creating a steep PDT dose gradient.

AIM

To determine how a high PDT selectivity can be maintained throughout the bladder wall considering other efficacy determining parameters, in particular, the average optical properties of the mucosal layer governing the fluence rate multiplication factor, as well as the bladder shape and the position of the emitter in relationship to the bladder wall.

APPROACH

We present three irradiance monitoring systems and evaluate their ability to enable selective bladder PDT considering previously determined photodynamic threshold values for the bladder cancer, mucosa and urothelium in a preclinical model, and the photosensitizer's specific uptake ratio. Monte Carlo-based light propagation simulations performed for six human bladders at the time of therapy for a range of tissue optical properties. The performance of one irradiance sensing device in a clinical phase 1B trial is presented to underline the impact of irradiance monitoring, and it is compared to the Monte Carlo-derived dose surface histogram.

RESULTS

Monte Carlo simulations showed that irradiance monitoring systems need to comprise at least three sensors. Light scattering inside the bladder void needs to be minimized to prevent increased heterogeneity of the irradiance. The dose surface histograms vary significantly depending on the bladder shape and bladder volume but are less dependent on tissue optical properties.

CONCLUSIONS

We demonstrate the need for adequate irradiance monitoring independent of a photosensitizer's specific uptake ratio.

Correlation between prostate volume measured by ultrasound and detrusor wall thickness in men with benign prostatic hypertrophy

Background:

Benign prostatic hypertrophy (BPH) causes subvesical urinary obstruction in the elderly. It leads to changes in the bladder and upper urinary tract. This may be progressive with subsequent morbidities and mortalities. This study aims at determining the relationship between ultrasound-measured prostate volume and detrusor wall thickness (DWT) in men with BPH.

Materials and Methods:

One hundred and ten patients who met the inclusion criteria and were diagnosed with clinical BPH were enrolled. They had no other identifiable cause of bladder outlet obstruction. The International Prostate Symptoms Score (IPSS), Quality of Life (QOL) score, prostate volume, and DWT were measured. Correlation between prostate volume and DWT was done using SPSS version 20.0 (IBM, SPSS, Chicago, IL, USA). A P-value less than 0.05 was considered significant.

Results:

The mean age of patients was 68.3 ± 10.2 years, with a range of 40–100 years. The mean prostate volume and DWT were 94.2 ± 68.4 cm3 and 5.9 ± 3.0 mm, respectively. Mean QOL was 4.77 ± 1.35. The highest IPSS was 35 and lowest was 2. Nocturia was the major IPSS subscore. There was a positive correlation between prostate volume and DWT in men with BPH (r = 0.37; P = 0.007). This is statistically significant.

Conclusion:

Ultrasound-measured prostate volume correlates positively with DWT in men with BPH. This is statistically significant and is able to determine progression of the disease. Coexisting large prostate volume and thickened detrusor wall are an indicator of disease progression and eventual need for surgical intervention. This prevents renal damage.

Sex Differences in Urothelial Bladder Cancer Survival

BACKGROUND

While urinary bladder cancer is consistently more common in men worldwide, women have poorer prognosis. The aim of this study was to outline sex differences in prognostic factors and clinical management and to explore whether these can explain the poorer urinary bladder cancer outcome in women.

PATIENTS AND METHODS

We performed a population-based cohort study including all patients diagnosed with urothelial bladder cancer between 1997 and 2014 at age 18 to 89 who had data recorded in the Swedish Urinary Bladder Cancer Register (n = 36,344). Female-to-male odds ratios for clinical management parameters were estimated by logistic regression. To quantify sex differences in bladder cancer-specific survival, we estimated empirical survival proportions and mortality rates as well as applied flexible parametric models to estimate female-to-male hazard ratios and survival proportions over follow-up. Adjusted models included age, year, World Health Organization grade, stage, marital status, education, health care region, birth country, and comorbidity.

RESULTS

Except for an adverse stage distribution in women, we found no evidence of unequal clinical management. Among those diagnosed with bladder cancer, women had a higher bladder cancer mortality (adjusted hazard ratio, 1.15; 95% confidence interval, 1.08-1.23) driven by muscle-invasive tumors (adjusted hazard ratio, 1.24; 95% confidence interval, 1.14-1.34). The female survival disadvantage was confined to the first 2 years after diagnosis.

CONCLUSION

The excess bladder cancer mortality in women is limited to those diagnosed with muscle-invasive tumors and cannot be explained by the examined clinicopathologic factors. Further investigations of sex differences in therapeutic procedures and outcomes, including complications, of muscle-invasive bladder cancer, must be performed.

FINITE ELEMENT ANALYSIS OF URINARY BLADDER WALL THICKNESS AT DIFFERENT PRESSURE CONDITION

In this work, a 3D urinary bladder was subjected to various pressure loading conditions mimicking the bladder filling volume. The bladder layer consisting of adventitia, detrusor and mucosa layer having different mechanical properties produced different deformation and stresses when subjected to the varying loads. The volume of the bladder changed to 231.34[Formula: see text]ml which was 128.91% higher than the assumed initial volume of 50[Formula: see text]ml on application of 18[Formula: see text]kPa of pressure. The detrusor layer which is thickest of the bladder wall reduced to 1.312[Formula: see text]mm from 4.4[Formula: see text]mm, recording a 108% change in its thickness at 18[Formula: see text]kPa pressure. The maximum von-Mises stress obtained were significantly higher in case of the Mucosa layer when compared to the detrusor and adventia layer. The unique layup of the bladder wall having different properties plays a major role in sustaining adverse pressure gradients and absorbing high stresses.

Structural, biomechanical and hemodynamic assessment of the bladder wall in healthy subjects

Aim

The aim of this study was to apply and evaluate three ultrasound methods to measure the bladder wall in a healthy population using high-resolution applications and to establish reference points and baselines for future research into lower urinary tract diseases, specifically to understand how lower urinary tract disorders affect the bladder wall and to find objective, non-invasive diagnostic tests.

Methods

The study was conducted on 116 healthy volunteers aged 19–79 years old with approximately 10 participants in each decade group.

Results

The following bladder parameters were recorded and measured using a GE LOGIQ E9 XDclear 2.0 ultrasound machine (GE Healthcare, Wauwatosa, WI, USA):

Full bladder wall thickness (BWT) and each of three bladder wall layers thickness (BWLT) – serosa, detrusor and mucosa;

Shear Wave Velocity (SWV) in m/s, using 2D Shear Wave Elastography (2D-SWE); and

Bladder wall blood circulation (Resistive Index, RI), using Duplex Doppler ultrasound.

All of the above measurements were recorded at three different urine filling volumes: V0 (20–50 mL), V2 (180–200 mL) and V4 (380–400 mL) with ten repeats for each measured parameter. As expected, BWT and BWLT correlated inversely with increasing bladder volume. While there are no large differences in the healthy bladders of men compared with women, or with age, some small, but statistically significant, differences revealed. BWT at V0 is greater in men, as is the detrusor thickness at VO, but there are no differences at other volumes or for other layers. There is a small, but statistically significant thickening of BWT and detrusor layer and increase in SWV with age in men at V0. SWE showed increase in SWV measured at 400 mL bladder volume across all gender and age groups. There was no change in bladder wall vessels RI with age, between gender groups or increasing bladder volume.

Conclusion

We used three ultrasound applications to obtain bladder wall reference data in healthy individuals and investigated the relationships between BWT, BWLT, SWV, RI and gender, age at three bladder volumes, for further studies into identifying and diagnosing different urinary bladder disorders. With further research, ultrasound could be used as a diagnostic test to differentiate bladder pathology in clinical practice.

Correlation of Ultrasonically Determined Bladder Wall Thickness and Prostatic Calcification With the Urinary, Psychosocial Dysfunction, Organ Specific, Infection and Neurological/Systemic Symptoms, and Tenderness Scoring System

OBJECTIVE

To evaluate ultrasonically determined bladder wall thickness (BWT) and prostatic calcification presence, in men with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), and to correlate the findings with patient characteristics and the urinary, psychosocial dysfunction, organ specific, infection and neurological/systemic symptoms, and tenderness (UPOINT) classification system.

MATERIAL AND METHODS

Between January 2008 and December 2017, data of 1294 patients diagnosed with chronic prostatitis, in a single urology clinic, meeting a number of selective inclusion/exclusion criteria, were retrospectively analyzed. Patients, compliant to fill out all requested questionnaires, between the ages of 21-65 years were included to the study. Exclusion criteria were noncompliance of filling out required questionnaires, acute and/or chronic bacterial prostatitis, history of genitourinary cancer, history of recent prostate surgery, and diagnosis of neurological diseases affecting the bladder.

RESULTS

The median patient age and UPOINT subdomain was determined as 37 (IQR = 13, range 21-65) and 2 (IQR = 1, range 0-5), respectively. Median values for BWT, National Institute of Health-Chronic Prostatitis Symptom Index (NIH-CPSI), and International Index of Erectile Function were 3 (IQR = 1, range 2-6, 7), 4 (IQR = 6, range 1-23), and 25 (IQR = 10, range 1-30), respectively. The presence of calcification demonstrated a significant association with total NIH-CPSI score and BWT, whereas its relation with age and total UPOINT score was insignificant. However in contrast to calcification status, BWT ≥3.3 showed a strong and statistically significant relation to all the described measurements.

CONCLUSION

Measurement of BWT can be used as an accessible and objective method for the diagnose of CP/CPPS according to UPOINT scoring system.

Recent advances in imaging and understanding interstitial cystitis

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating condition associated with intense pelvic pain and bladder storage symptoms. Since diagnosis is difficult, prevalence estimates vary with the methodology used. There is also a lack of proven imaging tools and biomarkers to assist in differentiation of IC/BPS from other urinary disorders (overactive bladder, vulvodynia, endometriosis, and prostatitis). Current uncertainty regarding the etiology and pathology of IC/BPS ultimately impacts its timely and successful treatment, as well as hampers future drug development. This review will cover recent developments in imaging methods, such as magnetic resonance imaging, that advance the understanding of IC/BPS and guide drug development.

Clinical validation of a novel thermophysical bladder model designed to improve the accuracy of hyperthermia treatment planning in the pelvic region

PURPOSE

Hyperthermia treatment planning for deep locoregional hyperthermia treatment may assist in phase and amplitude steering to optimize the temperature distribution. This study aims to incorporate a physically correct description of bladder properties in treatment planning, notably the presence of convection and absence of perfusion within the bladder lumen, and to assess accuracy and clinical implications for non muscle invasive bladder cancer patients treated with locoregional hyperthermia.

METHODS

We implemented a convective thermophysical fluid model based on the Boussinesq approximation to the Navier-Stokes equations using the (finite element) OpenFOAM toolkit. A clinician delineated the bladder on CT scans obtained from 14 bladder cancer patients. We performed (1) conventional treatment planning with a perfused muscle-like solid bladder, (2) with bladder content properties without and (3) with flow dynamics. Finally, we compared temperature distributions predicted by the three models with temperature measurements obtained during treatment.

RESULTS

Much higher and more uniform bladder temperatures are predicted with physically accurate fluid modeling compared to previously employed muscle-like models. The differences reflect the homogenizing effect of convection, and the absence of perfusion. Median steady state temperatures simulated with the novel convective model (3) deviated on average -0.6 °C (-12%) from values measured during treatment, compared to -3.7 °C (-71%) and +1.5 °C (+29%) deviation for the muscle-like (1) and static (2) models, respectively. The Grashof number was 3.2 ± 1.5 × 10⁵ (mean ± SD).

CONCLUSIONS

Incorporating fluid modeling in hyperthermia treatment planning yields significantly improved predictions of the temperature distribution in the bladder lumen during hyperthermia treatment.

Sonographic Reference Values for Bladder Wall Thickness, Detrusor Wall Thickness, and Bladder Weight in Apparently Healthy Adults in a Nigerian Population

The aim was to establish reference values of bladder wall thickness (BWT), detrusor wall thickness (DWT), and bladder weight (BW) in apparently healthy adults in a Nigerian population. Therefore, a cross-sectional study of healthy adult participants was conducted from May 2015 to April 2016. The urinary bladder was sonographically evaluated on a convenient sample of 384 adult participants. The BWT, DWT, and BW of the participants were measured and documented. The BW was estimated based on the surface area, thickness, and bladder muscle specific gravity. The mean BWT, DWT, and BW were 2.8 ± 0.3 mm, 1.3 ± 0.1 mm, and 23.3 ± 4.1 g, respectively. There was no statistically significant correlation between anthropometric variables with BWT, DWT, and BW except age, which had a weak positive correlation with BWT ( P = .05). This data set could be used for future research, in other parts of the country, for a possible nationwide nomogram.

Normal reference values for bladder wall thickness on CT in a healthy population

PURPOSE

To determine normal bladder wall thickness on CT in patients without bladder disease.

MATERIALS AND METHODS

Four hundred and nineteen patients presenting for trauma with normal CTs of the abdomen and pelvis were included in our retrospective study. Bladder wall thickness was assessed, and bladder volume was measured using both the ellipsoid formula and an automated technique. Patient age, gender, and body mass index were recorded. Linear regression models were created to account for bladder volume, age, gender, and body mass index, and the multiple correlation coefficient with bladder wall thickness was computed. Bladder volume and bladder wall thickness were log-transformed to achieve approximate normality and homogeneity of variance. Variables that did not contribute substantively to the model were excluded, and a parsimonious model was created and the multiple correlation coefficient was calculated. Expected bladder wall thickness was estimated for different bladder volumes, and 1.96 standard deviation above expected provided the upper limit of normal on the log scale.

RESULTS

Age, gender, and bladder volume were associated with bladder wall thickness (p = 0.049, 0.024, and < 0.001, respectively). The linear regression model had an R² of 0.52. Age and gender were negligible in contribution to the model, and a parsimonious model using only volume was created for both the ellipsoid and automated volumes (R² = 0.52 and 0.51, respectively).

CONCLUSION

Bladder wall thickness correlates with bladder wall volume. The study provides reference bladder wall thicknesses on CT utilizing both the ellipsoid formula and automated bladder volumes.

Development of a prediction model for late urinary incontinence, hematuria, pain and voiding frequency among irradiated prostate cancer patients

BACKGROUND AND PURPOSE

Incontinence, hematuria, voiding frequency and pain during voiding are possible side effects of radiotherapy among patients treated for prostate cancer. The objective of this study was to develop multivariable NTCP models for these side effects.

MATERIAL AND METHODS

This prospective cohort study was composed of 243 patients with localized or locally advanced prostate cancer (stage T1-3). Genito-urinary (GU) toxicity was assessed using a standardized follow-up program. The GU toxicity endpoints were scored using the Common Terminology Criteria for Adverse Events version 3.0 (CTCAE 3.0) scoring system. The full bladder and different anatomical subregions within the bladder were delineated. A least absolute shrinkage and selection operator (LASSO) logistic regression analysis was used to analyze dose volume effects on the four individual endpoints.

RESULTS

In the univariable analysis, urinary incontinence was significantly associated with dose distributions in the trigone (V55-V75, mean). Hematuria was significantly associated with the bladder wall dose (V40-V75, mean), bladder dose (V70-V75), cardiovascular disease and anticoagulants use. Pain during urinating was associated with the dose to the trigone (V50-V75, mean) and with trans transurethral resection of the prostate (TURP). In the final multivariable model urinary incontinence was associated with the mean dose of the trigone. Hematuria was associated with bladder wall dose (V75) and cardiovascular disease, while pain during urinating was associated with trigone dose (V75) and TURP. No significant associations were found for increase in voiding frequency.

CONCLUSIONS

Radiation-induced urinary side effects are associated with dose distributions to different organs as risk. Given the dose effect relationships found, decreasing the dose to the trigone and bladder wall may reduce the incidence of incontinence, pain during voiding and hematuria, respectively.

Non-invasive evaluation of lower urinary tract symptoms (LUTS) in men

Lower urinary tract symptoms (LUTS) are common in males over the age of 40 years old and are likely to increase with an aging population. Currently urodynamic studies are the gold standard to determine the aetiology of voiding dysfunction and LUTS. However, due to its invasive nature, a great number of non-invasive ultrasound based investigations have been developed to assess patients with symptomatic LUTS. The clinical application of non-invasive tests could potentially stratify patients who would require more invasive investigations and allow more precise patient directed treatment. A PubMed literature review was performed and we will discuss the non-invasive investigations that have been developed thus far, focusing on bladder wall and detrusor wall thickness (BWT & DWT), ultrasound estimated bladder weight (UEBW) and intravesical prostatic protrusion (IPP).

Lyso-thermosensitive liposomal doxorubicin for treatment of bladder cancer

PURPOSE

To evaluate lyso-thermosensitive liposomal doxorubicin (LTLD, ThermoDox®) in combination with loco-regional mild hyperthermia (HT) for targeted drug delivery to the bladder wall and potential treatment of bladder cancer.

MATERIAL AND METHODS

Porcine in vivo studies were performed with the following groups: (i) intravenous (IV) LTLD with hyperthermia (LTLD + HT); (ii) IV doxorubicin (DOX) with hyperthermia (IV DOX + HT) and (iii) IV LTLD without hyperthermia (LTLD - HT). Drug formulations were delivered via 30 min IV infusion coinciding with 1-h bladder irrigation (45 °C water for HT groups, 37 °C for non-HT group), followed by immediate bladder resection. DOX concentrations were measured in consecutive sections parallel to the bladder lumen by liquid chromatography following drug extraction. Computer models were developed to simulate tissue heating and drug release from LTLD.

RESULTS

Comparing mean DOX concentrations at increasing depths from the lumen to outer surface of the bladder wall, the ranges for LTLD + HT, IV DOX + HT and LTLD - HT, respectively, were 20.32-3.52 μg/g, 2.34-0.61 μg/g and 2.18-0.51 μg/g. The average DOX concentrations in the urothelium/lamina and muscularis, respectively, were 9.7 ± 0.67 and 4.09 ± 0.81 μg/g for IV LTLD + HT, 1.2 ± 0.39 and 0.86 ± 0.24 μg/g for IV DOX + HT, and 1.15 ± 0.38 and 0.62 ± 0.15 μg/g for LTLD - HT. Computational model results were similar to measured DOX levels and suggest adequate temperatures were reached within the bladder wall for drug release from LTLD.

CONCLUSIONS

Doxorubicin accumulation and distribution within the bladder wall was achieved at concentrations higher than with free IV doxorubicin by mild bladder hyperthermia combined with systemic delivery of LTLD.

Evaluation of hyoscine N-butyl bromide efficacy on the prevention of catheter-related bladder discomfort after transurethral resection of prostate: a randomized, double-blind control trial

BACKGROUND

Transurethral resection of prostate (TURP) is the most common treatment for benign prostatic hyperplasia (BPH). Urinary tract catheter is inserted post-operatively which results in catheter-related bladder discomfort (CRBD) in many patients. The purpose of this study was to assess the preventive effect of hyoscine N-butyl bromide on CRBD caused by a urinary tract catheter after TURP surgery in patients with BPH.

METHODS

Twenty-four and twenty-six patients in the treatment and control groups were enrolled, respectively. At the end of the surgery, slow intravenous injection of 20 mg hyoscine N-butyl bromide was administered to the patients of treatment group. The severity of CRBD was followed up at five different time periods and up to 2 h after surgery.

RESULTS

On arrival to PACU and after 30 min of injection, statistically significant less CRBD was seen in the treatment group comparing to the control group (P ≤ 0.05 and P ≤ 0.007). The total utilized meperidine dose during PACU stay and the time to discharge for the intervention group were significantly lower than those for the control group (P ≤ 0.0001) with no significant difference in adverse effects (P > 0.05).

CONCLUSIONS

Hyoscine N-butyl bromide could reduce the severity of CRBD related to TURP in patients with BPH and their need for analgesic consumption either. It shortened the length of stay in the recovery room. Regarding its availability and low cost, it can be an effective pain relief drug for CRBD discomfort related to TURP in BPH patients.

Epidermal Growth Factor Receptor (EGFR)-targeted Photoimmunotherapy (PIT) for the Treatment of EGFR-expressing Bladder Cancer

The use of light as a means of therapy for bladder cancer has a long history but has been hampered by a lack of tumor specificity and therefore, damage to the normal bladder mucosa. Here, we describe a targeted form of phototherapy called photoimmunotherapy (PIT), which targets EGFR-expressing bladder cancer. Anti-EGFR antibody panitumumab was labeled with the photoabsorber (PA), IRDye 700Dx (IR700), to create a panitumumab-IR700 antibody-PA conjugate that is activated by near-infrared radiation (NIR). Bladder cancer tissue microarray (TMA) and bladder cancer cell lines were analyzed for expression of EGFR. Mechanism of PIT-induced cell death was studied using proliferation assays, transmission electron microscopy (TEM), and production of reactive oxygen species. Finally, the in vivo effect was studied in xenografts. EGFR staining of TMAs showed that while most bladder cancers have expression of EGFR to a varying degree, squamous cell carcinomas (SCC) have the highest expression of EGFR. Panitumumab-IR700 activated by NIR light rapidly killed UMUC-5 cells, a bladder SCC line. Panitumumab alone, panitumumab-IR700 without NIR, or NIR alone had no effect on cells. TEM demonstrated that cell death is due to necrosis. Singlet oxygen species contributed toward cell death. NIR-PIT with panitumumab-IR700 reduced growth compared with only panitumumab-IR700-treated UMUC-5 xenograft tumors. PIT is a new targeted treatment for bladder cancer. Panitumumab-IR700-induced PIT selectively kills EGFR-expressing bladder cancer cells in vitro and in vivo and therefore warrants further therapeutic studies in orthotopic xenografts of bladder cancer and ultimately in patients. Mol Cancer Ther; 16(10); 2201-14. ©2017 AACR.

Change of Ultrasound Estimated Bladder Weight and Bladder Wall Thickness After Treatment of Bladder Outlet Obstruction With Dutasteride

OBJECTIVES

To investigate the change of bladder wall hypertrophy to relieve bladder outlet obstruction (BOO) by treatment with 5α-reductase inhibitor.

METHODS

Men who have BOO confirmed by urodynamic study (BOO index ≥40) were treated with dutasteride 0.5 mg once a day for 6 months. We measured ultrasound estimated bladder weight (UEBW), UEBW divided by body surface area (UEBW/BSA), and bladder wall thickness (BWT) before and after treatment. Changes in LUTS parameters were assessed by using the International Prostate Symptom Score, uroflowmetry, residual urine volume, prostate volume, serum prostate-specific antigen (PSA), and LUTS outcome scores (LOS). Correlation between the change of LUTS parameters and UEBW, UEBW/BSA, and BWT were evaluated. We assessed the changes of bladder wall hypertrophy according to the results of benefit, satisfaction, and willingness to continue (BSW) questionnaire.

RESULTS

Thirty patients completed the 6-month study. The mean UEBW was 47.10 ± 7.79 g before and 50.07 ± 5.39 g after dutasteride treatment (P = 0.259). The mean UEBW/BSA was 26.47 ± 4.30 g/m² before and 28.2 ± 3.53 g/m² after treatment (P = 0.253), and there was no definite change in mean BWT after treatment (P = 0.301). Most LUTS parameters including LOS significantly improved. Increased BOO index value was related to decreased BWT (ρ = 0.361, P = 0.049). There was no definite change in mean UEBW, UEBW/BSA, and BWT according to the results of the BSW questionnaire.

CONCLUSIONS

There was no change in UEBW, UEBW/BSA and BWT despite improving most clinical parameters suggesting BOO. The changes of bladder wall hypertrophy parameters still have limitations to directly reflect the relief of BOO.

Feasibility of photoacoustic evaluations on dual-thermal treatment of ex vivo bladder tumors

A variety of thermal therapeutic methods have been investigated to treat bladder tumors but often cause bowel injury and bladder wall perforation due to high treatment dosage and limited clinical margins. The objective of the current study is to develop a dual-thermal modality to deeply coagulate the bladder tumors at low thermal dosage and to evaluate therapeutic outcomes with high contrast photoacoustic imaging (PAI). High intensity focused ultrasound (HIFU) is combined with 532 nm laser light to enhance therapeutic depth during thermal treatments on artificial tumor-injected bladder tissue ex vivo. PAI is employed to identify the margins of the tumors pre- and post-treatments. The dual-thermal modality achieves 3- and 1.8-fold higher transient temperature changes and 2.2- and 1.5-fold deeper tissue denaturation than laser and HIFU, respectively. PAI vividly identifies the position of the injected tumor and entails approximately 7.9 times higher image contrast from the coagulated tumor as that from the untreated tumor. Spectroscopic analysis exhibits that both 740 nm and 760 nm attains the maximum photoacoustic amplitudes from the treated areas. The proposed PAI-guided dual-thermal treatments (laser and HIFU) treatments can be a feasible therapeutic modality to treat bladder tumors in a controlled and efficient manner.

A novel algorithm for the non-invasive detection of bladder outlet obstruction in men with lower urinary tract symptoms

Objective

To determine the ability of bladder wall thickness (BWT) in combination with non-invasive variables to distinguish patients with bladder outlet obstruction (BOO).

Patients and methods

Patients completed the International Prostate Symptom Score (IPSS) questionnaire and prostate size was measured by transrectal ultrasonography (US). Pressure-flow studies were performed to determine the urodynamic diagnosis. BWT was measured at 250-mL bladder filling using transabdominal US. Recursive partition analysis (RPA) recursively partitions data for relating independent variable(s) to a dependent variable creating a tree of partitions. It finds a set of cuts of the dependent variable(s) that best predict the independent variable, by searching all possible cuts until the desired fit is reached. RPA was used to test the ability of the combined data of BWT, maximum urinary flow rate (Q_max), post-void residual urine volume (PVR), IPSS, and prostate size to predict BOO.

Results

In all, 72 patients were included in the final analysis. The median BWT, voided volumes, PVR, mean Q_max, and IPSS were significantly higher in patients who had an Abrams/Griffiths (A/G) number of >40 (55 patients) compared to those with an A/G number of ≤40 (17 patients). RPA revealed that the combination of BWT and Q_max gave a correct classification in 61 of the 72 patients (85%), with 92% sensitivity and 65% specificity, 87% positive predictive value, and 76% negative predictive value (NPV) for BOO (area under the curve 0.85). The positive diagnostic likelihood ratio of this reclassification fit was 2.6.

Conclusions

It was possible to combine BWT with Q_max to create a new algorithm that could be used as a screening tool for BOO in men with lower urinary tract symptoms.

Characterization of miRNA-regulated networks, hubs of signaling, and biomarkers in obstruction-induced bladder dysfunction

Bladder outlet obstruction (BOO) induces significant organ remodeling, leading to lower urinary tract symptoms accompanied by urodynamic changes in bladder function. Here, we report mRNA and miRNA transcriptome sequencing of bladder samples from human patients with different urodynamically defined states of BOO. Patients' miRNA and mRNA expression profiles correlated with urodynamic findings. Validation of RNA sequencing results in an independent patient cohort identified combinations of 3 mRNAs (NRXN3, BMP7, UPK1A) and 3 miRNAs (miR-103a-3p, miR-10a-5p, miR-199a-3p) sufficient to discriminate between bladder functional states. All BOO patients shared cytokine and immune response pathways, TGF-β and NO signaling pathways, and hypertrophic PI3K/AKT signaling pathways. AP-1 and NFkB were dominant transcription factors, and TNF-α was the top upstream regulator. Integrated miRNA-mRNA expression analysis identified pathways and molecules targeted by differentially expressed miRNAs. Molecular changes in BOO suggest an increasing involvement of miRNAs in the control of bladder function from the overactive to underactive/acontractile states.

Increased detrusor collagen is associated with detrusor overactivity and decreased bladder compliance in men with benign prostatic obstruction

Background

This study aimed to investigate the relationship between detrusor collagen content and urodynamic parameters in men with benign prostatic obstruction.

Material and methods

Nineteen consecutive patients undergoing open prostatectomy for bladder outlet obstruction (BOO) due to benign prostatic hyperplasia (BPH) were evaluated. Urodynamic tests were performed in all patients. BOO and detrusor contractility were assessed with the BOO index (BOOI) and the bladder contractility index (BCI), respectively. A bladder fragment was obtained during prostatectomy. Eight cadaveric organ donors composed the control group. Bladder sections were stained with picrosirius red and hematoxylin-eosin. The collagen to smooth muscle ratio (C/M) in the detrusor was measured and its relationship with urodynamic parameters was investigated.

Results

Seven (36.8%) patients were operated on due to lower urinary tract symptoms and 12 (63.2%) had urinary retention. The mean prostate volume was 128.6 cm³ ± 32.3 cm³, the mean BOOI was 76.4 ± 33.0, and the mean BCI was 116.1 ± 33.7. The mean C/M in BPH patients and controls were 0.43 ± 0.13 and 0.33 ± 0.09, respectively (P = 0.042). A negative correlation was shown between C/M and bladder compliance (r = –0.488, P = 0.043). The C/M was increased in BPH patients with detrusor overactivity (DO) compared to those without DO (0.490 ± 0.110 and 0.360 ± 0.130, respectively; P = 0.030) and also in patients with urinary retention (P = 0.002). No correlation was shown between C/M and maximum cystometric capacity, BOOI, or BCI.

Conclusion

Men with BOO/BPH have increased detrusor collagen content which is associated with decreased bladder compliance, detrusor overactivity, and urinary retention.

Clinical significance of incidentally detected bladder wall thickening on computed tomography

PURPOSE

To evaluate the clinical significance of incidentally detected bladder wall thickening (BWT) on computed tomography (CT).

METHODS

A retrospective analysis was performed on 34,793 cystoscopy cases between January 2004 and December 2013. Among these, patients who underwent cystoscopy for the sole indication of incidentally detected BWT on CT were selected. Patients were categorized into the diffuse or focal group depending on the extent of BWT. Suspicious lesions on cystoscopy were biopsied to confirm histologic subtype. The incidence and predictive factors of bladder malignancy were examined.

RESULTS

A total of 167 (0.5%) patients received cystoscopy for incidentally detected BWT on CT, of which 11 (6.6%) patients were diagnosed with bladder malignancy. When a suspicious lesion was identified on cystoscopy, 11 of 25 (44%) patients were found to have a bladder malignancy. Of the 15 patients with diffuse BWT, 5 (33.3%) were diagnosed with bladder malignancy, consisting of carcinoma in situ in 2 patients, high-grade carcinoma in 2 patients and muscle invasive disease in 1 patient. Of the 10 patients with focal BWT, 6 (60.0%) were diagnosed with bladder malignancy, of which 3 patients had high-grade disease. On multivariate logistic regression analysis, focal BWT [95% confidence interval (CI) 1.400-25.357, P = 0.016] and atypical cells in urine cytology (95% CI 2.631-63.446, P = 0.002) were positively associated with bladder malignancy.

CONCLUSIONS

Incidentally detected BWT on CT can be suggestive of bladder malignancy. Therefore, further work-up including cystoscopy and urine cytology should be performed to assess bladder malignancy.

Bladder ultrasonography for diagnosing detrusor overactivity: test accuracy study and economic evaluation

BACKGROUND

Urodynamics (UDS) has been considered the gold standard test for detrusor overactivity (DO) in women with an overactive bladder (OAB). Bladder ultrasonography to measure bladder wall thickness (BWT) is less invasive and has been proposed as an alternative test.

OBJECTIVES

To estimate the reliability, reproducibility, accuracy and acceptability of BWT in women with OAB, measured by ultrasonography, in the diagnosis of DO; to explore the role of UDS and its impact on treatment outcomes; and to conduct an economic evaluation of alternative care pathways.

DESIGN

A cross-sectional test accuracy study.

SETTING

22 UK hospitals.

PARTICIPANTS

687 women with OAB.

METHODS

BWT was measured using transvaginal ultrasonography, and DO was assessed using UDS, which was performed blind to ultrasonographic findings. Intraobserver and interobserver reproducibility were assessed by repeated measurements from scans in 37 and 57 women, respectively, and by repeated scans in 27 women. Sensitivity and specificity were computed at pre-specified thresholds. The smallest real differences detectable of BWT were estimated using one-way analysis of variance. The pain and acceptability of both tests were evaluated by a questionnaire. Patient symptoms were measured before testing and after 6 and 12 months using the International Consultation on Incontinence modular Questionnaire Overactive Bladder (short form) (ICIQ-OAB) questionnaire and a global impression of improvement elicited at 12 months. Interventions and patient outcomes were analysed according to urodynamic diagnoses and BWT measurements. A decision-analytic model compared the cost-effectiveness of care strategies using UDS, ultrasonography or clinical history, estimating the cost per woman successfully treated and the cost per quality-adjusted life-year (QALY).

RESULTS

BWT showed very low sensitivity and specificity at all pre-specified cut-off points, and there was no evidence of discrimination at any threshold (p = 0.25). Extensive sensitivity and subgroup analyses did not alter the interpretation of these findings. The smallest detectable difference in BWT was estimated to be 2 mm. Pain levels following both tests appeared relatively low. The proportion of women who found the test 'totally acceptable' was significantly higher with ultrasonography than UDS (81% vs. 56%; p < 0.001). Overall, subsequent treatment was highly associated with urodynamic diagnosis (p < 0.0001). There was no evidence that BWT had any relationship with the global impression of improvement responses at 20 months (p = 0.4). Bladder ultrasonography was more costly and less effective than the other strategies. The incremental cost-effectiveness ratio (ICER) of basing treatment on the primary clinical presentation compared with UDS was £491,500 per woman successfully treated and £60,200 per QALY. Performing a UDS in those women with a clinical history of mixed urinary incontinence had an ICER of £19,500 per woman successfully treated and £12,700 per QALY compared with the provision of urodynamic to all women. For DO cases detected, UDS was the most cost-effective strategy.

CONCLUSION

There was no evidence that BWT had any relationship with DO, regardless of the cut-off point, nor any relationship to symptoms as measured by the ICIQ-OAB. Bladder ultrasonography has no diagnostic or prognostic value as a test in this condition. Furthermore, despite its greater acceptability, BWT measurement was not sufficiently reliable or reproducible.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN46820623.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 7. See the NIHR Journals Library website for further project information.

Overview of bladder heating technology: matching capabilities with clinical requirements

Moderate temperature hyperthermia (40-45°C for 1 h) is emerging as an effective treatment to enhance best available chemotherapy strategies for bladder cancer. A rapidly increasing number of clinical trials have investigated the feasibility and efficacy of treating bladder cancer with combined intravesical chemotherapy and moderate temperature hyperthermia. To date, most studies have concerned treatment of non-muscle-invasive bladder cancer (NMIBC) limited to the interior wall of the bladder. Following the promising results of initial clinical trials, investigators are now considering protocols for treatment of muscle-invasive bladder cancer (MIBC). This paper provides a brief overview of the devices and techniques used for heating bladder cancer. Systems are described for thermal conduction heating of the bladder wall via circulation of hot fluid, intravesical microwave antenna heating, capacitively coupled radio-frequency current heating, and radiofrequency phased array deep regional heating of the pelvis. Relative heating characteristics of the available technologies are compared based on published feasibility studies, and the systems correlated with clinical requirements for effective treatment of MIBC and NMIBC.