Transurethral bladder tumor resection can cause seeding of cancer cells into the bloodstream

Randomized Comparison of Magnetic Resonance Imaging Versus Transurethral Resection for Staging New Bladder Cancers: Results From the Prospective BladderPath Trial

PURPOSE

Transurethral resection of bladder tumor (TURBT) is the initial staging procedure for new bladder cancers (BCs). For muscle-invasive bladder cancers (MIBCs), TURBT may delay definitive treatment. We investigated whether definitive treatment can be expedited for MIBC using flexible cystoscopic biopsy and multiparametric magnetic resonance imaging (mpMRI) for initial staging.

PATIENTS AND METHODS

We conducted a prospective open-label, randomized study conducted within 17 UK hospitals (registered as ISRCTN 35296862). Participants with suspected new BC were randomly assigned 1:1 to TURBT-staged or mpMRI-staged care, with minimization factors of sex, age, and clinician visual assessment of stage. Blinding was not possible. Patients unable/unwilling to undergo mpMRI or with previous BC were ineligible. The study had two stages with separate primary outcomes of feasibility and time to correct treatment (TTCT) for MIBC, respectively.

RESULTS

Between May 31, 2018, and December 31, 2021, 638 patients were screened, and 143 participants randomly assigned to TURBT (n = 72; 55 males, 15 MIBCs) or initial mpMRI (n = 71; 53 males, 14 MIBCs). For feasibility, 36 of 39 (92% [95% CI, 79 to 98]) participants with suspected MIBC underwent mpMRI. The median TTCT for participants with MIBC was significantly shorter with initial mpMRI (n = 12, 53 days [95% CI, 20 to 89] v n = 14, 98 days [95% CI, 72 to 125] for TURBT, log-rank P .02). There was no detriment for participants with non-MIBC (median TTCT: n = 30, 17 days [95% CI, 8 to 25] for mpMRI v n = 28, 14 days [95% CI, 10 to 29] for TURBT, log-rank P = .67). No serious adverse events were reported.

CONCLUSION

The mpMRI-directed pathway led to a 45-day reduction in TTCT for MIBC. Incorporating mpMRI ahead of TURBT into the standard pathway was beneficial for all patients with suspected MIBC.

Circulating tumour DNA and circulating tumour cells in bladder cancer - from discovery to clinical implementation

Liquid biopsies, indicating the sampling of body fluids rather than solid-tissue biopsies, have the potential to revolutionize cancer care through personalized, noninvasive disease detection and monitoring. Circulating tumour DNA (ctDNA) and circulating tumour cells (CTCs) are promising blood-based biomarkers in bladder cancer. Results from several studies have shown the clinical potential of ctDNA and CTCs in bladder cancer for prognostication, treatment-response monitoring, and early detection of minimal residual disease and disease recurrence. Following successful clinical trial evaluation, assessment of ctDNA and CTCs holds the potential to transform the therapeutic pathway for patients with bladder cancer - potentially in combination with the analysis of urinary tumour DNA - through tailored treatment guidance and optimized disease surveillance.

An updated systematic review, meta-analysis, and trial sequential analysis of the efficacy and safety of en bloc transurethral resection vs. conventional transurethral resection for nonmuscle-invasive bladder tumor

OBJECTIVE

En bloc transurethral resection of bladder tumor (ERBT) for nonmuscular-invasive bladder tumor (NMIBC) has been used in clinical practice, but its efficacy and safety have not been conclusional. We aimed to evaluate the efficacy and safety of ERBT and conventional transurethral resection of bladder tumor (cTURBT) for NMIBC.

METHODS

Randomized controlled trials (RCTs) comparing ERBT and cTURBT in the treatment of NMIBC were searched in Pubmed, Embase, Clinicaltrials.gov, and Cochrane; 12 RCTs were included for systematic review and meta-analysis using RevMan 5.4.

RESULTS

A total of 12 RCTs involving 2097 patients with NMIBC were included and analyzed. The results showed the rate of identification of detrusor muscle in specimens [odds ratio (OR) 1.90; P = 0.03] was higher in ERBT group, and bladder perforation (OR 0.30; P = 0.004), obturator nerve reflex (OR 0.18; P = 0.001), catheter indwelling time (MD -0.64; P = 0.002), length of hospital stay (MD -0.58; P = 0.002), tumor recurrence rate 3 months after surgery (OR 0.42; P = 0.03), tumor recurrence rate 6 months after surgery (OR 0.21; P = 0.007), the recurrence rate of the same site 1 year after surgery (OR 0.23; P < 0.0001) and bleeding rate (OR 0.30; P = 0.0005) were significantly lower in ERBT group than that in cTURBT group. There was no significant difference in residual tumor (OR 0.62; P = 0.07), Re-TURBT (OR 0.71; P = 0.19), hemoglobin deficit (MD -0.81; P = 0.29), urethral stricture (OR 0.67; P = 0.42), resection time (MD 2.31; P = 0.16), operative time (MD 1.17; P = 0.49), 1 year (OR 0.61; P = 0.13), 2 years (OR 0.94; P = 0.76), 3-year tumor recurrence rate (OR 1.03; P = 0.86) and the risk of progression at 12 month (OR 0.68; P = 0.79) between the two groups.

CONCLUSIONS

Our results showed that ERBT can improve the rate of identification of detrusor muscle in specimens and reduce the 3-month, 6-month tumor recurrence rate and recurrence rate of the same site 1 year after surgery. In addition, ERBT has fewer complications, and shorter catheter indentation time and hospital stay. The laser ERBT can also decrease tumor residual rate and re-TURBT.

Optimal energy source selection strategies for en bloc resection in non-muscle invasive bladder cancer: a systematic review and network meta-analysis

OBJECTIVE

This research aimed to identify the most effective energy source for en bloc resection of non-muscle-invasive bladder cancer (NMIBC) by a systematic review and network meta-analysis of randomized controlled trials (RCTs) and observational studies. We assessed and contrasted the effectiveness and safety of various energy modalities used in en bloc resection (ERBT) with those employed in conventional transurethral resection of bladder tumor (cTURBT).

METHODS

A thorough search was conducted in PubMed, EMBASE, Cochrane, and Web of Science (WOS) to discover relevant articles published till August 29, 2024. Research comparing en bloc resection using various energy sources (such as hybrid knife, holmium laser, thulium laser, green-light laser, monopolar, and bipolar devices) to conventional transurethral resection of bladder tumor (cTURBT) was included. A network meta-analysis was performed using Stata/MP 18.0. Standardized mean differences (SMD) were computed for continuous outcomes, whilst relative risks (RR) were used for dichotomous outcomes. Nine clinical outcomes were assessed: duration of surgery, length of hospital stay, catheterization duration, irrigation duration, volume of intraoperative blood transfusion, 12-month recurrence rate, bladder perforation rate, incidence of obturator nerve reflex, and presence of detrusor muscle in the resected specimen. (PROSPERO ID: CRD42024623881).

RESULTS

The study included 37 research, including 8 randomized controlled trials (RCTs) and 29 high-quality non-randomized controlled trials (NRCTs), with a total of 4973 patients involved. The network meta-analysis revealed that ERBT was much better than cTURBT in the majority of outcomes. Hybrid knife and laser technologies (holmium, thulium, and green-light lasers) shown superior efficacy regarding decreased surgical length, diminished 12-month recurrence rates, and fewer problems. Hybridknife proved to be the most advantageous energy source for various results, while cTURBT consistently exhibited the least effective performance across all metrics.

CONCLUSION

En bloc resection surpasses traditional TURBT in the management of NMIBC, with various energy modalities exhibiting distinct benefits. Among the assessed energy sources, laser technologies and hybrid knives regularly surpassed monopolar and bipolar devices. These findings provide critical direction for urologists in selecting the most suitable energy source for en bloc resection in NMIBC, emphasizing the need for individualized decision-making based on the patient's distinct variables and tumor attributes.

Improved epirubicin delivery selectivity to bladder cancer achieved by functionalized hydroxyethyl starch-based prodrug

Bladder instillation of chemo-therapeutic agents is common for bladder cancer (BC) treatment, however, due to the poor tissue selectivity of chemotherapeutic agents, this method suffers from bladder irritation or even chemical cystitis. Here, we designed a hydroxyethyl starch-based prodrug for epirubicin (EPI) using a pH-sensitive hydrazone linker and folate as the active targeting moiety (FA-HES-hyd-EPI) to achieve delivery selectivity. Prodrug micelles decorated with FA (FA-m), with diameter of 203.6 ± 7.1 nm and EPI loading of 5.80 ± 0.129 %, were prepared by self-assemble method. FA-m was found with improved cellular uptake and stronger cytotoxicity over EPI. An orthotopic BC model was established with FA receptor over-expression, and FA-m showed significantly higher accumulation at tissue and cell levels compared with the FA-free counterpart. Besides, the systemic exposure of FA-m was significantly lower than EPI (AUC0-t: 28.11 ± 7.23 ng/mL/h versus 11.60 ± 4.27 ng/mL/h). More importantly, FA-m showed stronger in vivo tumor growth inhibition with average tumor weight of 0.26 ± 0.21 mg (EPI group: 1.695 ± 0.62 mg), and better safety according to body weight and HE staining data. Overall, the combination of active targeting and pH responsive prodrug strategies was a feasible way to achieve selective EPI delivery to BC via instillation that improved both therapeutic effect and safety.

Spontaneous Necrosis of a High-Risk Bladder Tumor Under Immunotherapy for Concurrent Malignant Melanoma: Role of BRAF Mutations and PD-L1 Expression

Background: Bladder cancer (BC) is a heterogeneous malignancy, and predicting response to immune checkpoint inhibitors (ICIs) remains a challenge. Herein, we investigate a high-risk bladder tumor, which developed during anti-BRAF/MEK therapy for a concurrent advanced BRAF-V600E-positive malignant melanoma (MM) and subsequently underwent complete spontaneous necrosis following Nivolumab immunotherapy, only to recur thereafter while still under the same treatment. This unique scenario provided an opportunity to investigate the roles of BRAF gene mutations in BC pathogenesis, respectively, of PD-L1 expression in immunotherapy response prediction. Methods: We retrospectively analyzed BC specimens obtained via transurethral resection at two critical time-points: prior to the complete spontaneous necrosis under Nivolumab (prenecrosis) and after tumor recurrence postnecrosis (postnecrosis). The BRAF gene mutation status was evaluated using quantitative polymerase chain reaction (qPCR). PD-L1 expression was assessed by immunohistochemistry (IHC), quantified using the combined positive score (CPS), and a cutoff of ≥10 for positivity. Results: Neither pre- nor postnecrosis BC samples harbored BRAF gene mutations. Prenecrosis PD-L1 expression (CPS = 5) indicated a minimal likelihood of response to immunotherapy. However, complete spontaneous necrosis occurred under Nivolumab, followed by recurrence with further reduced PD-L1 expression (CPS = 1). Conclusions: The complete BC regression challenges the conventional role of PD-L1 as a sole predictive biomarker for immunotherapy. This study also highlights the potential role of BRAF/MEK inhibitors in BC oncogenesis and underscores the need for alternative biomarkers, such as tumor mutation burden (TMB) and circulating tumor DNA (ctDNA), to guide treatment selection in BC better.

En bloc resection of large bladder tumor: is it feasible and reasonable?

PURPOSE OF REVIEW

Transurethral resection of bladder tumor (TURBT) remains the basis of bladder tumor diagnosis and an effective means of treating nonmuscle invasive bladder cancer (NMIBC). There are several limitations to this procedure: TURBT may cause free floating of malignant cells in the bladder and as a result re-implantation and early recurrence. Also, it does not allow the pathologist to define the correct spatial orientation of the specimen. The development of en bloc resection of bladder tumor (ERBT) has helped overcome the abovementioned key disadvantages of TURBT. However, many urologists doubt whether this approach is feasible for treating larger tumors.

RECENT FINDINGS

In this review, it is shown that ERBT of large bladder tumor (>3 cm) is in fact a feasible and well tolerated method. Although there is a lack of comparative data proving its advantages over TURBT, en bloc in large tumor seems to result in better local cancer control (due to higher prevalence of detrusor specimen, lower need for re-TURBT), lower rate of relapse outside the resection area (due to lower risk of tumor cells circulation), and higher quality of pathology specimen.

SUMMARY

Despite the skepticism of some surgeons, potential difficulties caused by larger tumor size may be overcome easily, and most agree that tumor size should not limit the implementation of the method in their daily practice.

Metastasis development in non-muscle-invasive bladder cancer

Non-muscle-invasive bladder cancer (NMIBC) is the most common type of bladder cancer presentation and is characterized by a varying probability of recurrence and progression. Sporadically, patients with NMIBC might also develop tumour metastases without any pathological evidence of muscle-invasive disease within the bladder, a condition known as metastatic NMIBC. In the published literature, this phenomenon is limited to several case reports and small reviews, with few data regarding the possible aetiologies. Several possible factors can be potentially associated with metastatic NMIBC, including tumour understaging, the number of transurethral resection procedures received by the patient, the presence of circulating tumour cells, the modality used for diagnostic cystoscopy and possible gender-associated differences. In this Perspective, our aim was to integrate and report currently available data on this relatively rare entity and provide some potential aetiological explanations.

The Role of Maximal TURBT in Muscle-Invasive Bladder Cancer: Balancing Benefits in Bladder Preservation and Beyond

Radical cystectomy with lymph node dissection and urinary diversion is the gold-standard treatment for non-metastatic muscle-invasive bladder cancer (MIBC). However, in patients who refuse cystectomy, or in whom cystectomy carries a high risk, bladder-preserving therapies remain potential options. Bladder preservation therapies can include maximal debulking transurethral resection of bladder tumor (TURBT), concurrent chemoradiation therapy, followed by cystoscopy to assess response. At this time, maximal TURBT is recommended for patients prior to the initiation of chemoradiation therapy or in patients with residual bladder tumors after the completion of chemoradiation therapy. That being said, TURBT carries significant risks such as bladder perforation, bleeding, and infection, ultimately risking delayed systemic treatment. Hence, understanding its role within trimodal therapy is crucial to avoid undue suffering in patients. Herein, we review the current literature on the impact of debulking TURBT in non-metastatic MIBC.

Image directed redesign of bladder cancer treatment pathways: the BladderPath RCT

Background

Transurethral resection of bladder tumour has been the mainstay of bladder cancer staging for > 60 years. Staging inaccuracies are commonplace, leading to delayed treatment of muscle-invasive bladder cancer. Multiparametric magnetic resonance imaging offers rapid, accurate and non-invasive staging of muscle-invasive bladder cancer, potentially reducing delays to radical treatment.

Objectives

To assess the feasibility and efficacy of the introducing multiparametric magnetic resonance imaging ahead of transurethral resection of bladder tumour in the staging of suspected muscle-invasive bladder cancer.

Design

Open-label, multistage randomised controlled study in three parts: feasibility, intermediate and final clinical stages. The COVID pandemic prevented completion of the final stage.

Setting

Fifteen UK hospitals.

Participants

Newly diagnosed bladder cancer patients of age ≥ 18 years.

Interventions

Participants were randomised to Pathway 1 or 2 following visual assessment of the suspicion of non-muscle-invasive bladder cancer or muscle-invasive bladder cancer at the time of outpatient cystoscopy, based upon a 5-point Likert scale: Likert 1-2 tumours considered probable non-muscle-invasive bladder cancer; Likert 3-5 possible muscle-invasive bladder cancer. In Pathway 1, all participants underwent transurethral resection of bladder tumour. In Pathway 2, probable non-muscle-invasive bladder cancer participants underwent transurethral resection of bladder tumour, and possible muscle-invasive bladder cancer participants underwent initial multiparametric magnetic resonance imaging. Subsequent therapy was determined by the treating team and could include transurethral resection of bladder tumour.

Main outcome measures

Feasibility stage: proportion with possible muscle-invasive bladder cancer randomised to Pathway 2 which correctly followed the protocol. Intermediate stage: time to correct treatment for muscle-invasive bladder cancer.

Results

Between 31 May 2018 and 31 December 2021, of 638 patients approached, 143 participants were randomised; 52.1% were deemed as possible muscle-invasive bladder cancer and 47.9% probable non-muscle-invasive bladder cancer. Feasibility stage: 36/39 [92% (95% confidence interval 79 to 98%)] muscle-invasive bladder cancer participants followed the correct treatment by pathway. Intermediate stage: median time to correct treatment was 98 (95% confidence interval 72 to 125) days for Pathway 1 versus 53 (95% confidence interval 20 to 89) days for Pathway 2 [hazard ratio 2.9 (95% confidence interval 1.0 to 8.1)], p = 0.040. Median time to correct treatment for all participants was 37 days for Pathway 1 and 25 days for Pathway 2 [hazard ratio 1.4 (95% confidence interval 0.9 to 2.0)].

Limitations

For participants who underwent chemotherapy, radiotherapy or palliation for multiparametric magnetic resonance imaging-diagnosed stage T2 or higher disease, it was impossible to conclusively know whether these were correct treatments due to the absence of histopathologically confirmed muscle invasion, this being confirmed radiologically in these cases. All patients had histological confirmation of their cancers. Due to the COVID-19 pandemic, we were unable to realise the final stage.

Conclusion

The multiparametric magnetic resonance imaging-directed pathway led to a substantial 45-day reduction in time to correct treatment for muscle-invasive bladder cancer, without detriment to non-muscle-invasive bladder cancer participants. Consideration should be given to the incorporation of multiparametric magnetic resonance imaging ahead of transurethral resection of bladder tumour into the standard pathway for all patients with suspected muscle-invasive bladder cancer. The improved decision-making accelerated time to treatment, even though many patients subsequently needed transurethral resection of bladder tumour. A proportion of patients can avoid transurethral resection of bladder tumour completely, reducing costs and morbidity, given the much lower cost of magnetic resonance imaging and biopsy compared to transurethral resection of bladder tumour.

Future work

Further work to cross-correlate with the recently developed Vesical Imaging-Reporting and Data System will improve accuracy and aid dissemination. Longer follow-up to examine the effect of the pathway on outcomes is also required. Incorporation of liquid deoxyribonucleic acid-based biomarkers may further improve the quality of decision-making and should also be investigated further.

Study registration

This study is registered as ISRCTN 35296862.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR135775) and is published in full in Health Technology Assessment; Vol. 28, No. 42. See the NIHR Funding and Awards website for further award information.

Effect of different anaesthetic techniques on the prognosis of patients with colorectal cancer after resection: a systematic review and meta-analysis

Background

The effect of total intravenous anaesthesia (TIVA) and inhalation anaesthesia (IA) on the prognosis of patients with colorectal cancer after resection is controversial. This study aimed to explore the effects of different anaesthesia methods on the postoperative prognosis of colorectal cancer.

Methods

PubMed, Embase and Cochrane Library databases were searched for relevant literature from each database's inception until 18 November 2023. The literature topic was to compare the effects of TIVA and IA on the prognosis of patients undergoing colorectal cancer resection.

Results

Six studies were selected for meta-analysis. The studies involved 111043 patients, with a trial size of 1001-88184 people. A statistically significant difference was observed in the overall survival (OS) between colorectal cancer patients administered TIVA and IA (hazard ratio [HR], 0.83; 95% confidence interval [CI], 0.70-0.99), but none in recurrence-free survival (RFS) (HR, 0.99; 95% CI, 0.90-1.08). In the subgroup analysis of OS, no statistically significant difference was observed between colorectal cancer patients administered TIVA and IA in Asia (HR, 0.77; 95% CI, 0.57-1.05), and not in Europe (HR, 0.99; 95% CI, 0.93-1.06). Regarding tumour location, no significant association was found between TIVA and IA in the colon, rectum and colorectum ((HR, 0.70; 95% CI, 0.38-1.28), (HR, 0.95; 95% CI, 0.83-1.08) and (HR, 0.99; 95% CI, 0.93-1.06), respectively).

Conclusion

OS differed significantly between patients administered TIVA and IA when undergoing colorectal cancer resection, but no difference was observed in RFS. The prognostic effects of TIVA and IA differed.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023453185, identifier CRD42023453185.

Radiomics Prediction of Muscle Invasion in Bladder Cancer Using Semi-Automatic Lesion Segmentation of MRI Compared with Manual Segmentation

Conventional radiomics analysis requires the manual segmentation of lesions, which is time-consuming and subjective. This study aimed to assess the feasibility of predicting muscle invasion in bladder cancer (BCa) with radiomics using a semi-automatic lesion segmentation method on T2-weighted images. Cases of non-muscle-invasive BCa (NMIBC) and muscle-invasive BCa (MIBC) were pathologically identified in a training cohort and in internal and external validation cohorts. For bladder tumor segmentation, a deep learning-based semi-automatic model was constructed, while manual segmentation was performed by a radiologist. Semi-automatic and manual segmentation results were respectively used in radiomics analyses to distinguish NMIBC from MIBC. An equivalence test was used to compare the models' performance. The mean Dice similarity coefficients of the semi-automatic segmentation method were 0.836 and 0.801 in the internal and external validation cohorts, respectively. The area under the receiver operating characteristic curve (AUC) were 1.00 (0.991) and 0.892 (0.894) for the semi-automated model (manual) on the internal and external validation cohort, respectively (both p < 0.05). The average total processing time for semi-automatic segmentation was significantly shorter than that for manual segmentation (35 s vs. 92 s, p < 0.001). The BCa radiomics model based on semi-automatic segmentation method had a similar diagnostic performance as that of manual segmentation, while being less time-consuming and requiring fewer manual interventions.

Combined use of a 980‑nm diode laser and preoperative intravesical instillation of pirarubicin for the prevention of short‑term recurrence of non‑muscle invasive bladder cancer: A pilot study

At present, transurethral resection of bladder tumors (TURBT) is the main surgical method for treating non-muscle invasive bladder cancer (NMIBC), but its postoperative recurrence needs to be prevented. The aim of the present study was to investigate the efficacy of a 980-nm diode laser combined with preoperative intravesical instillation of pirarubicin (THP) for the prevention of NMIBC recurrence. The data of 120 patients with NMIBC who underwent transurethral resection between May 2021 and July 2022 were retrospectively collected, and these patients were followed up. The patients were divided into four groups based on the surgical method used and preoperative intravesical instillation of THP as follows: i) 980-nm diode laser with THP (LaT); ii) 980-nm diode laser alone (La); iii) TURBT with THP (TUT); and iv) TURBT alone (TU). Clinicopathological variables, postoperative complications and short-term outcomes among the aforementioned groups were analyzed. The blood loss volume and the incidence of perforation and delayed bleeding were significantly lower in the LaT and La groups compared with those in the TUT and TU groups. The days of bladder irrigation, catheter extubation and postoperative hospitalization were significantly shorter in the LaT and La groups compared with the TUT and TU groups. The detection rate of suspicious lesions was significantly higher in the THP irrigation groups (LaT and TUT) compared with that in the saline irrigation groups (La and TU). Tumor diameter and number, 980-nm laser and THP irrigation were shown to be independent risk factors in the Cox regression analysis. In addition, the recurrence-free survival (RFS) rate of the LaT group was significantly higher than that of the other three groups. In conclusion, a 980-nm diode laser can effectively reduce intraoperative blood loss and the incidence of perforation, and accelerate postoperative recovery. Preoperative intravesical instillation of THP is conducive to identifying suspicious lesions. The combination of a 980-nm laser with preoperative THP intravesical instillation can significantly prolong RFS time.

Liquid biopsies for detection, surveillance, and prognosis of urothelial cancer: a future standard?

INTRODUCTION

Liquid biopsies are used for the detection of tumor-specific elements in body fluid. Their application in prognosis and diagnosis of muscle/non-muscle invasive bladder cancer (MIBC/NMIBC) or upper tract urothelial cancer (UTUC) remains poorly known and rarely mentioned in clinical guidelines.

AREAS COVERED

Herein, we provide an overview of current data regarding the use of liquid biopsies in urothelial tumors.

EXPERT OPINION

Studies that were included analyzed liquid biopsies using the detection of circulating tumor cells (CTCs), deoxyribonucleic acid (DNA), ribonucleic acid (RNA), exosomes, or metabolomics. The sensitivity of blood CTC detection in patients with localized cancer was 35% and raised to 50% in patients with metastatic cancer. In NMIBC patients, blood CTC was associated with poor prognosis, whereas discrepancies were seen in MIBC patients. Circulating plasma DNA presented a superior sensitivity to urine and was a good indicator for diagnosis, follow-up, and oncological outcome. In urine, specific bladder cancer (BC) microRNA had an overall sensitivity of 85% and a specificity of 86% in the diagnosis of urothelial cancer. These results are in favor of the use of liquid biopsies as biomarkers for in urothelial cancer management.

The accuracy of cystoscopy in predicting muscle invasion in newly diagnosed bladder cancer patients

PURPOSE

The prognosis of muscle-invasive bladder cancer (MIBC) has not improved for three decades. Transurethral resection of the bladder tumor (TURBT) is the standard procedure for local tumor staging. TURBT has several limitations, including the spread of tumor cells. Therefore, an alternative is needed in patients with suspected MIBC. Recent studies have shown that mpMRI is very accurate in staging bladder tumors. Because the diagnostic efficacy of urethrocystoscopy (UCS) has been reported as good as the efficacy of mpMRI to predict muscle invasion we performed this prospective multicenter study in which we compare UCS with pathology.

METHODS

From July 2020 until March 2022, 321 patients with suspected primary BC in seven participating Dutch hospitals were included in this study. A flexible UCS was performed by urologists, physician assistants, or residents. Predictions of muscle invasion using a 5-point Likert scale alongside the histopathology data were recorded. The sensitivity, specificity, predictive values, and 95% confidence intervals were determined using a standard contingency table.

RESULTS

Of the 321 included patients, 232 (72.3%) received a histopathological diagnosis of non-muscle-invasive bladder cancer (NMIBC) and 71 (22.1%) were histopathologically diagnosed as MIBC. In 2 patients (0.6%), classification was not possible (Tx). Cystoscopy predicted muscle invasion with a sensitivity of 71.8% (95% CI 59.9-81.9), and a specificity of 89.9% (95% CI 85.4-93.3). This corresponds to a positive predictive value (PPV) of 67.1% and a negative predictive value (NPV) of 91.7%.

CONCLUSION

Our study shows a moderate accuracy of cystoscopy to predict muscle invasion. This result does not support the use of cystoscopy only instead of TURBT for local staging.

Urodrill - a novel MRI-guided endoscopic biopsy technique to sample and molecularly classify muscle-invasive bladder cancer without fractionating the specimen during transurethral resection

The current diagnostic pathway for patients with muscle-invasive bladder cancer (MIBC), which involves with computed tomography urography, cystoscopy, and transurethral resection of the bladder (TURB) to histologically confirm MIBC, delays definitive treatment. The Vesical Imaging-Reporting and Data System (VI-RADS) has been suggested for MIBC identification using magnetic resonance imaging (MRI), but a recent randomized trial reported misclassification in one-third of patients. We investigated a new endoscopic biopsy device (Urodrill) for histological confirmation of MIBC and assessment of molecular subtype by gene expression in patients with VI-RADS 4 and 5 lesions on MRI. In ten patients, Urodrill biopsies were guided by MR images to the muscle-invasive portion of the tumor via a flexible cystoscope under general anesthesia. During the same session, conventional TURB was subsequently performed. A Urodrill sample was successfully obtained in nine of ten patients. MIBC was verified in six of nine patients, and seven of nine samples contained detrusor muscle. In seven of eight patients for whom a Urodrill biopsy sample was subjected to RNA sequencing, single-sample molecular classification according to the Lund taxonomy was feasible. No complications related to the biopsy device occurred. A randomized trial comparing this new diagnostic pathway for patients with VI-RADS 4 and 5 lesions and the current standard (TURB) is warranted.

Patient summary

We report on a novel biopsy device for patients with muscle-invasive bladder cancer that facilitates histology analysis and molecular characterization of tumor samples.

Clinical Validation of a Size-Based Microfluidic Device for Circulating Tumor Cell Isolation and Analysis in Renal Cell Carcinoma

Renal cell carcinoma (RCC) presents as metastatic disease in one third of cases. Research on circulating tumor cells (CTCs) and liquid biopsies is improving the understanding of RCC biology and metastases formation. However, a standardized, sensitive, specific, and cost-effective CTC detection technique is lacking. The use of platforms solely relying on epithelial markers is inappropriate in RCC due to the frequent epithelial-mesenchymal transition that CTCs undergo. This study aimed to test and clinically validate RUBYchip™, a microfluidic label-free CTC detection platform, in RCC patients. The average CTC capture efficiency of the device was 74.9% in spiking experiments using three different RCC cell lines. Clinical validation was performed in a cohort of 18 patients, eight non-metastatic (M0), five metastatic treatment-naïve (M1TN), and five metastatic progressing-under-treatment (M1TP). An average CTC detection rate of 77.8% was found and the average (range) total CTC count was 6.4 (0-27), 101.8 (0-255), and 3.2 (0-10), and the average mesenchymal CTC count (both single and clustered cells) was zero, 97.6 (0-255), and 0.2 (0-1) for M0, M1TN, and M1TP, respectively. CTC clusters were detected in 25% and 60% of M0 and M1TN patients, respectively. These results show that RUBYchip™ is an effective CTC detection platform in RCC.

Liquid Biopsy in Bladder Cancer

Fluid biopsy based on circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), exosome, and circulating RNA in blood and body fluids has gained attention. Here, the recent findings and issues related to liquid biopsy in bladder cancer are discussed, with a focus on CTCs, ctDNA, urinary tumor DNA, exosome, and circulating RNA.

The 980 nm diode laser treatment for non-muscle-invasive bladder tumor with en bloc technique: single-center experience

Background

Transurethral resection of the bladder tumor (TURBT) is one of the most established urological procedures for the treatment of the primary non-muscle-invasive bladder cancer (NMIBC). The aim of the study is to evaluate the efficacy and safety of 980 nm diode laser as a treatment for primary NMIBC.

Methods

Eighty-eight patients with NMIBC were treated by en bloc transurethral resection with 980 nm diode laser, and 76 patients were treated by plasmakinetic transurethral resection from May 2016 to July 2019 at the Department of Urology, Tangdu Hospital, Air Force Medical University. The clinical data were collected and compared between the two groups.

Results

The bladder irrigation time was shortened in 980 nm diode laser group compared to that of plasmakinetic transurethral resection group (4.1 ± 0.6 vs 13.1 ± 3.1 h, p < 0.001). A total of 13.2% (10/76) patients experienced obturator nerve reflex, and 5.3% (4/76) experienced delayed bleeding in plasmakinetic transurethral resection group, while no obturator nerve reflex and delayed bleeding cases were observed in 980 nm diode laser group (p < 0.05). The postoperative catheterization and hospitalization time showed no significant difference between the two groups. The median follow-up time was 27 months (13–38 months). No significant difference in the recurrence rate was observed between the two groups.

Conclusions

The 980 nm diode laser is an effective and safe tool in transurethral resection of NMIBC using en bloc technique. It has less perioperative complications and shortened bladder irrigation time.

Complete transurethral resection of bladder tumor before radical cystectomy is not a risk factor for organ-confined bladder cancer: A case-control study

Objectives

Materials and methods

Results

Conclusions

Systematic review and meta-analysis of randomized controlled trials of perioperative outcomes and prognosis of transurethral en-bloc resection vs. conventional transurethral resection for non-muscle-invasive bladder cancer

OBJECTIVES

This article aimed to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) of perioperative outcomes and prognosis of transurethral en-bloc resection versus conventional transurethral resection for non-muscle-invasive bladder cancer (NMIBC).

METHODS

We searched MEDLINE, Web of Science, and the Cochrane Controlled Register of Trials (CENTRAL) to find eligible RCTs. The studies were classified by version 2 of the Cochrane risk-of-bias tool for randomized trials. Review Manager 5.4.0 was used to evaluate the data. The certainty of the evidence was assessed using the Guideline Development Tool by GRADEpro GDT.

RESULTS

Seven RCTs with 1142 patients was included in the present study. The results indicated that bladder perforation (OR = 0.17; 95% CI 0.05 to 0.67; P = 0.01), obturator nerve reflex (OR = 0.03; 95% CI 0.01 to 0.13; P < 0.00001), residual tumor (OR = 0.24; 95% CI 0.08 to 0.77; P = 0.02) and repeat transurethral resection of bladder tumor (re-TURBT) (OR = 0.54; 95% CI 0.34 to 0.85; P = 0.008) were significantly reduced in the en-bloc resection group than the conventional resection group. However, there were no significant differences in hemoglobin deficit (p = 0.31), urethral stricture (p = 0.47), and detrusor muscle presence (P = 0.16) between both groups. Besides, resection time (p = 0.25), operative time (p = 0.20), catheter dwell time (p = 0.24), and length of hospital stay (p = 0.16) were similar in the two groups. Meanwhile, en-bloc resection yielded no advantage for the 3-month (P = 0.11), 6-month (P = 0.05), 1-year (P = 0.61), 2-year (P = 0.53), and 3-year (P = 0.26) tumor recurrence rates.

CONCLUSIONS

Our meta-analysis shows that transurethral en-bloc resection is associated with comparable outcomes to conventional transurethral resection for recurrence-free survival in NMIBC patients. En-bloc resection is more feasible and safer than conventional resection for NMIBC, with fewer intraoperative complications, less residual tumor, and less re-TURBT.

The application value of multi-parameter cystoscope in improving the accuracy of preoperative bladder cancer grading

PURPOSE

To develop and validate a preoperative cystoscopic-based predictive model for predicting postoperative high-grade bladder cancer (BCa), which could be used to guide the surgical selection and postoperative treatment strategies.

MATERIALS AND METHODS

We retrospectively recruited 366 patients with cystoscopy biopsy for pathology and morphology evaluation between October 2010 and January 2021. A binary logistic regression model was used to assess the risk factors for postoperative high-grade BCa. Diagnostic performance was analyzed by plotting receiver operating characteristic curve and calculating area under the curve (AUC), sensitivity, specificity. From January 2021 to July 2021, we collected 105 BCa prospectively to validate the model's accuracy.

RESULTS

A total of 366 individuals who underwent transurethral resection of bladder tumor (TURBT) or radical cystectomy following cystoscopy biopsy were included for analysis. 261 (71.3%) had a biopsy pathology grade that was consistent with postoperative pathology grade. We discovered five cystoscopic parameters, including tumor diameter, site, non-pedicled, high-grade biopsy pathology, morphology, were associated with high-grade BCa. The established multi-parameter logistic regression model ("JSPH" model) revealed AUC was 0.917 (P < 0.001). Sensitivity and specificity were 86.2% and 84.0%, respectively. And the consistency of pre- and post-operative high-grade pathology was improved from biopsy-based 70.5% to JSPH model-based 85.2%. In a 105-patients prospective validation cohort, the consistency of pre- and post-operative high-grade pathology was increased from 63.1 to 84.2% after incorporation into JSPH model for prediction.

CONCLUSION

The cystoscopic parameters based "JSPH model" is accurate at predicting postoperative pathological high-grade tumors prior to operations.

Removal of Circulating Tumor Cells from Blood Samples of Cancer Patients Using Highly Magnetic Nanoparticles: A Translational Research Project

The count of circulating tumor cells (CTCs) has been associated with a worse prognosis in different types of cancer. Perioperatively, CTCs detach due to mechanical forces. Diagnostic tools exist to detect and isolate CTCs, but no therapeutic technique is currently available to remove CTCs in vivo from unprocessed blood. The aim of this study was to design and test new magnetic nanoparticles to purify whole blood from CTCs. Novel magnetic carbon-coated cobalt (C/Co) nanoparticles conjugated with anti-epithelial cell adhesion molecule (EpCAM) antibodies were synthesized, and their antifouling and separation properties were determined. The newly developed C/Co nanoparticles showed excellent separation and antifouling properties. They efficiently removed tumor cells that were added to healthy subjects’ blood samples, through an anti-EpCAM antibody interaction. The nanoparticles did not interact with other blood components, such as lymphocytes or the coagulation system. In blood samples of carcinoma patients suffering from metastatic disease, on average, ≥68% of CTCs were removed. These nanoparticles could prompt the development of a blood purification technology, such as a dialysis-like device, to perioperatively remove CTCs from the blood of cancer patients in vivo and potentially improve their prognosis.

The Prognostic Value of the Circulating Tumor Cell-Based Four mRNA Scoring System: A New Non-Invasive Setting for the Management of Bladder Cancer

Bladder cancer (BC) is one of the most expensive lifetime cancers to treat because of the high recurrence rate, repeated surgeries, and long-term cystoscopy monitoring and treatment. The lack of an accurate classification system predicting the risk of recurrence or progression leads to the search for new biomarkers and strategies. Our pilot study aimed to identify a prognostic gene signature in circulating tumor cells (CTCs) isolated by ScreenCell devices from muscle invasive and non-muscle invasive BC patients. Through the PubMed database and Cancer Genome Atlas dataset, a panel of 15 genes modulated in BC with respect to normal tissues was selected. Their expression was evaluated in CTCs and thanks to the univariate and multivariate Cox regression analysis, EGFR, TRPM4, TWIST1, and ZEB1 were recognized as prognostic biomarkers. Thereafter, by using the risk score model, we demonstrated that this 4-gene signature significantly grouped patients into high- and low-risk in terms of recurrence free survival (HR = 2.704, 95% CI = 1.010−7.313, Log-rank p < 0.050). Overall, we identified a new prognostic signature that directly impacted the prediction of recurrence, improving the choice of the best treatment for BC patients.

Medical Image Diagnostic Value of Computed Tomography for Bladder Tumors

OBJECTIVE

To study computed tomography (CT) imaging characteristics of bladder tumors, to explore the value of CT in tumor diagnosis, and to identify the relevant factors of CT missed diagnosis so that medical staff can be more accurate in the diagnosis of bladder tumors.

METHODS

To retrospectively analyze the CT manifestations of 153 bladder tumor cases confirmed by paraffin pathology in our hospital and to study the difference between the benign and CT imaging features. CT indicators mainly include the number, location, morphology, calcification, bladder wall smoothness, CT value, degree of enhancement, and invasion of surrounding tissues and organs. Then, we retrospectively analyze 17 cases of CT missed diagnosis of bladder tumors, analyze related factors, and discuss the role of CT in the diagnosis of bladder tumors.

RESULTS

This study has shown that with the help of CT images, the diagnosis rate of bladder tumors has been greatly improved. Of the 153 patients studied, noninvasive urothelial carcinoma accounted for 18.95% of all benign and malignant bladder tumors, invasive urothelial carcinoma accounted for 67.93%, prostatic metastatic carcinoma and inflammatory myofibroblastoma accounted for 8.47%, pheochromocytoma accounted for 1.31%, inverted papilloma accounted for 1.31%, tubular choriocarcinoma accounted for 0.63%, and endocystitis accounted for 1.31%. In addition, the blood supply level, CT index bladder wall smoothness, and CT value are also statistically significant (P < 0.05).

CONCLUSIONS

CT is of high value in the diagnosis of bladder tumors, and benign and malignant bladder tumors have CT and CT imaging features. The size of bladder tumors is related to the missed diagnosis rate of CT. The application of CT examination technology can improve the accuracy of diagnosis of bladder tumors.

Effects of robot-assisted versus hand-assisted nephroureterectomy on circulating tumor cells for upper urinary tract urothelial carcinoma

To compare perioperative circulating tumor cells (CTC) in primary upper tract urothelial carcinoma (UTUC) patients who underwent hand-assisted retroperitoneoscopic nephroureterectomy (HANU) or robotic-assisted nephroureterectomy (RANU). A total of 29 patients received RANU (n = 10) or HANU (n = 19). Peripheral blood samples were collected before, 24 h after surgery (POh24) and on postoperative day 28 (POD28). The demographic and pathologic data are similar in both groups. RANU had a longer operative time (p = 0.031), less bleeding volume (p = 0.004), and comparable pain sore (p = 0.169). The mean CTC numbers before surgery (2.4 vs. 2.3, p = 0.482), POh24 (2.4 vs. 1.9, p = 0.668) and POD28 (0.5 vs. 0.6, p = 0.280) were not significant different among groups. The amount of CTCs in both groups decreased and reached similar level on POD28. No significant difference of overall and intravesical recurrence rate between the two approaches. In comparison to RANU, more surgical manipulation does not affect tumor cell translocation into the bloodstream in UTUC patients who received HANU. However, a longer follow-up would be needed for the final comparison of tumor recurrence.

Potential candidates for en bloc resection among patients with primary and recurrent bladder tumours

INTRODUCTION

Transurethral resection (TURB) is the gold standard treatment for non-muscle invasive bladder cancer (NMIBC). However, conventional TURB is possibly part of the mechanism leading to the high recurrence rate in NMIBC and the need for repeated procedures, as the method with piecemeal resection of the tumour violates basic oncological principles and compromises pathological examination. En bloc resection (EBR) could potentially overcome these flaws by improving pathological quality and thereby reducing the need for re-resections and could potentially also lower the risk of tumour seeding leading to early recurrences. With this study, we aimed to evaluate tumour characteristics in a consecutive cohort of patients undergoing conventional TURB in order to estimate the proportion of procedures eligible for EBR, findings at re-resection, and early recurrence rate.

METHODS

All TURBs performed at a single large University Hospital in a 12 month period were manually reviewed. Based on tumour size and appearance, patients were registered as candidates or non-candidate for EBR.

RESULTS

A total of 600 TURBs were reviewed. Overall, 25% of procedures were found to be eligible for EBR. The most frequent reason for not being a candidate was tumour diameter <1 cm. Re-resections were done after 10.5% of the procedures, where the residual tumour was found in 28.6% of these. Within 6 months, 21.2% had a recurrence.

CONCLUSION

We found approximately 25% of all TURBs to be eligible for EBR. Based on a relatively low recurrence rate, we conclude that future studies on EBR with recurrence rate as the primary endpoint will require large patient cohorts.

Comparing an Imaging-guided Pathway with the Standard Pathway for Staging Muscle-invasive Bladder Cancer: Preliminary Data from the BladderPath Study

Transurethral resection of bladder tumour (TURBT) is central to the diagnosis of muscle-invasive bladder cancer (MIBC). With the oncological safety of TURBT unknown, staging inaccuracies commonplace, and correct treatment of MIBC potentially delayed, multiparametric magnetic resonance imaging (mpMRI) may offer rapid, accurate, and noninvasive diagnosis of MIBC. BladderPath is a randomised trial comparing risk-stratified (5-point Likert scale) image-directed care with TURBT for patients with newly diagnosed BC. To date, we have screened 279 patients and randomised 113. Here we report on the first 100 participants to complete staging: 48 in pathway 1 (TURBT) and 52 in pathway 2 (mpMRI for possible MIBC, Likert 3-5). Fifty of 52 participants designated Likert 1-2 (probable NMIBC) from both pathways were confirmed as having NMIBC (96%). Ten of 11 cases diagnosed as NMIBC by mpMRI have been pathologically confirmed as NMIBC, and 10/15 cases diagnosed as MIBC by mpMRI have been treated as MIBC (5 participants underwent TURBT). The specificity of mpMRI for identification of MIBC remains a limitation. These initial experiences indicate that it is feasible to direct possible MIBC patients to mpMRI for staging instead of TURBT. Furthermore, a 5-point Likert scale accurately identifies patients with low risk of MIBC (Likert 1-2), and flexible cystoscopy biopsies appear sufficient for diagnosing BC. PATIENT SUMMARY: We are conducting a clinical trial to assess whether some bladder tumour surgery can be replaced by magnetic resonance imaging scans to determine the stage of the cancer in patients whose tumours appear to be invasive. Our early data suggest that this approach is feasible. The data also show that using a visual score ('Likert scale') can help to identify bladder tumours that are very unlikely to be invasive, and that taking a biopsy in the outpatient clinic when first inspecting the bladder via a camera (diagnostic flexible cystoscopy) is useful for confirming bladder cancer.

The Use of BT-ESD Technology under General Intravenous Anesthesia in the Treatment of Nonmuscle Invasive Bladder Cancer and the Effect of PI3K/Akt Signaling Pathway on Tumor Recurrence

Objective. The objective is to investigate the effect of minimally invasive treatment of nonmuscle invasive bladder cancer (NMIBC) by transurethral endoscopic submucosal dissection of bladder tumor (BT-ESD) under general intravenous anesthesia and the expression of Akt in NMIBC and to study the effect of upregulation of intracellular phosphatidylinositol kinase (PI3K)/protein kinase B (Akt) on tumor recurrence. Method. 130 patients with NMIBC were selected as the research subjects, including 101 males and 29 females. The patients were divided into transurethral resection of bladder tumor (TURBT) group, BT-ESD learning group A (early 20 cases of chief surgeon), and BT-ESD learning group B (follow-up cases of the chief surgeon). The general information (male and female prevalence ratio and average age), operation duration, postoperative bladder irrigation duration, postoperative indwelling catheter time, postoperative hospitalization time, and postoperative complications were compared among the patients in all groups. The normal bladder tissues and pathological tissues of NMIBC patients were stained by immunohistochemistry. Results. No significant difference is identified in age among the three groups ( $P>0.05$ ), but there are significant differences in the operation duration, postoperative bladder irrigation time, postoperative indwelling catheter time, and postoperative hospital stay ( $P>0.05$ ). At the same time, compared with BT-ESD group A and BT-ESD group B, the number of postoperative complications in TURBT group is statistically different ( $P<0.05$ ). Akt has a strong positive expression in the nucleus of patients, which indicates that Akt activated by cellular PI3K will form the PI3K/Akt signaling pathway and reduce the recurrence rate of bladder tumor.

Circulating tumor cell detection methods in renal cell carcinoma: A systematic review

Circulating tumor cells (CTCs) have a potential role as the missing renal cell carcinoma (RCC) biomarker. However, the available evidence is limited, and detection methods lack standardization, hindering clinical use. We performed a systematic review on CTC enrichment and detection methods, and its role as a biomarker in RCC. Full-text screening identified 54 studies. Reviewed studies showed wide heterogeneity, low evidence level, and high risk of bias. Various CTC detection platforms and molecular markers have been used, but none has proven to be superior. CTC detection and CTC count seem to correlate with staging and survival outcomes, although evidence is inconsistent. CTC research is still in an exploratory phase, particularly in RCC. Further studies are still necessary to achieve a standardization of techniques, molecular markers, CTC definitions, and terminology. This is essential to ascertain the role of CTCs as a biomarker and guide future liquid biopsy research in RCC.

Long-term Follow-up After En Bloc Transurethral Resection of Non-muscle-invasive Bladder Cancer: Results from a Single-center Experience

BACKGROUND

En bloc resection (ERBT) is a valid alternative to piecemeal resection for non-muscle-invasive bladder cancer (NMIBC), guaranteeing pathological outcomes. However, very few studies investigated long-term oncological outcomes of ERBT.

OBJECTIVE

To report long-term oncological outcome of ERBT.

DESIGN SETTING AND PARTICIPANTS

This is a retrospective analysis of prospectively collected data. We included patients who underwent ERBT from June 2010 to February 2014, and were diagnosed with NMIBC at pathology evaluation.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary study endpoint was recurrence-free survival at 5 yr. Secondary outcomes were presence of detrusor muscle, recurrence rate at the first follow-up cystoscopy, progression to muscle-invasive bladder cancer (MIBC) at 5 yr, and factors associated with long-term oncological outcomes. Kaplan-Meier curves were used to describe recurrence-free survival time. A univariate analysis was used to investigate factors associated with recurrence.

RESULTS AND LIMITATIONS

Overall, 74 patients were included in this study. The median age was 71 (66-76) yr. Most of the patients presented with only one bladder tumor, and the median tumor diameter was 2 (interquartile range [IQR] 1-2.5) cm. After histopathological examination, eight, 35, and 31 patients were diagnosed with low-, intermediate-, and high-risk disease, respectively. All the en bloc resected tumors showed the presence of detrusor muscle. The median follow-up was 72 (IQR 66-90) mo. The recurrence rate at the first follow-up cystoscopy was 5.4% (four out of 74 patients). Overall, 57 (77%) patients were free of recurrence at 5 yr. No progression to MIBC was observed: progression-free survival was 100%. Limitations include retrospective design and small size.

CONCLUSIONS

Our findings showed that ERBT for NMIBC presents an optimal long-term oncological outcome. Further studies with larger cohorts are necessary for confirming our preliminary results and for a direct comparison with the traditional piecemeal resection.

PATIENT SUMMARY

In case of superficial bladder tumors, transurethral resection of the entire tumor and its base in one piece seems to provide good long-term results in terms of recurrence and progression rates.

Systemic dissemination of tumor cells during transurethral resection in patients with bladder tumor and its clinical relevance: A follow up study

OBJECTIVE

Tumor cells are shed during transurethral resection of bladder tumor (TURBT) and form the basis for use of single dose immediate chemotherapy instillation to reduce recurrences. Systemic dissemination of these cells along with the irrigation fluid is also possible but not consistently proven. In this study, we evaluated such dissemination of tumor cells into the circulation during TURBT and its clinical impact.

METHODS

Patients with primary presentation of bladder tumor who underwent TURBT were included. Peripheral venous blood samples before and after TURBT were analyzed for circulating tumor cells (CTCs) using flow-cytometry. A CD45 negative cell with positive expression of cytokeratin 18, 19, and EpCam was defined as CTC. The CTC counts, pre and post TURBT, were compared and correlated with final histopathology. The patients were also followed up for any local and/or systemic recurrences.

RESULTS

Nine (16.98%) out of 53 patients developed a measurable rise in CTCs after TURBT. All of these patients had high grade and muscle invasive disease. Overall, a measurable rise in CTCs was seen in 9 out of 17 (52.94%) patients with muscle invasive disease. There was no difference in the clinico-pathological stage or the status of cystectomy and/or chemotherapy between those who did or did not show a rise in CTCs. On follow up, 7 patients with muscle invasive disease developed local and/or systemic recurrences and the rise in CTCs was not found to be associated with adverse oncological outcomes.

CONCLUSIONS

This study confirms the hypothesis of inadvertent dissemination of tumor cells into the circulation during TURBT, especially in patients with high grade and muscle invasive disease. The long-term oncological impact of such dissemination remains to be confirmed.

En Bloc Tumor Resection, Optical Molecular Imaging, and the Potential Synergy of the Combination of the Two Techniques in Bladder Cancer

Although transurethral resection of bladder tumor is the golden standard for the treatment of non-muscle invasive bladder cancer, this surgical procedure still has some serious drawbacks. For example, piecemeal resection of tumor tissue results in exfoliated tumor cells dissemination and implantation, and fragmented tumor specimens make it difficult for pathologists to accurately assess the pathological stage and histologic grade. En bloc tumor resection follows the basic principle of oncological surgery and provides an intact tumor specimen containing detrusor muscle for pathologists to make accurate histopathological assessment. However, there is no robust clinical evidence that en bloc tumor resection is superior to conventional resection in terms of oncological outcomes. Considering the high recurrence rate, small or occult tumor lesions may be overlooked and incomplete tumor resection may occur during white light cystoscopy-assisted transurethral resection. Molecular fluorescent tracers have the ability to bind tumor cells with high sensitivity and specificity. Optical molecular imaging mediated by it can detect small or occult malignant lesions while minimizing the occurrence of false-positive results. Meanwhile, optical molecular imaging can provide dynamic and real-time image guidance in the surgical procedure, which helps urologists to accurately determine the boundary and depth of tumor invasion, so as to perform complete and high-quality transurethral tumor resection. Integrating the advantages of these two technologies, optical molecular imaging-assisted en bloc tumor resection shows the potential to improve the positive detection rate of small or occult tumor lesions and the quality of transurethral resection, resulting in high recurrence-free and progression-free survival rates.

MR-Guided Adaptive Radiotherapy for Bladder Cancer

Radiotherapy has an important role in the curative and palliative treatment settings for bladder cancer. As a target for radiotherapy the bladder presents a number of technical challenges. These include poor tumor visualization and the variability in bladder size and position both between and during treatment delivery. Evidence favors the use of magnetic resonance imaging (MRI) as an important means of tumor visualization and local staging. The availability of hybrid systems incorporating both MRI scanning capabilities with the linear accelerator (MR-Linac) offers opportunity for in-room and real-time MRI scanning with ability of plan adaption at each fraction while the patient is on the treatment couch. This has a number of potential advantages for bladder cancer patients. In this article, we examine the technical challenges of bladder radiotherapy and explore how magnetic resonance (MR) guided radiotherapy (MRgRT) could be leveraged with the aim of improving bladder cancer patient outcomes. However, before routine clinical implementation robust evidence base to establish whether MRgRT translates into improved patient outcomes should be ascertained.

The validity, reliability, and reviewer acceptance of VI-RADS in assessing muscle invasion by bladder cancer: a multicenter prospective study

OBJECTIVE

To assess diagnostic validity and reliability of VI-RADS in predicting muscle invasion by bladder cancer (BCa) and evaluate reviewer acceptance of VI-RADS for clinical routine.

METHODS

A prospective multicenter study enrolled 331 patients with suspected/untreated BCa who underwent preoperative multiparametric MRI examination (mp-MRI) of the urinary bladder. Four experienced radiologists independently evaluated all mp-MRI using VI-RADS. The diagnostic validity of VI-RADS for predicting muscle invasion by BCa was calculated using histopathology of the first transurethral resection bladder tumor (TURBT) and second TURBT as the reference standards. The kappa statistics (κ) were applied to assess the interreader agreement (IRA). Reviewer acceptance was evaluated with questionnaires.

RESULTS

The risk of muscle invasion in VI-RADS 2, 3, 4, and 5 after the first and second TURBT was 21.8%, 45.8%, 69.6%, and 96.4% and 24.4%, 58.3%, 87%, and 99.2%, respectively. The overall diagnostic validity of VI-RADS was high. The optimal cut-off value for predicting muscle invasion after first TURBT was > VI-RADS 3 (sensitivity = 84.1% and specificity = 92.3%), and after second TURBT was > VI-RADS 2 (sensitivity = 89.9% and specificity = 90.1%). VI-RADS categorization showed a very good IRA (κ = 0.93). Reviewers fully agreed with the statement, "The application of structured reporting of bladder tumor should be encouraged" (score = 20).

CONCLUSIONS

VI-RADS showed high diagnostic validity and reliability for predicting muscle invasion by BCa, especially VI-RADS 4 and 5. However, VI-RADS 2 and 3 require further modifications to enhance their diagnostic validity. VI-RADS is highly encouraged to be used in daily practice.

KEY POINTS

• VI-RADS showed high diagnostic validity and reliability in predicting BCa muscle invasion, especially VI-RADS 4 and 5. • In VI-RADS 2 and 3, we observed a notable percentage of BCa with muscle invasion and this would require further modifications to enhance the diagnostic validity for these scores. • Overall VI-RADS is well-accepted by radiologists who recommend it for daily practice.

Recurrence of Subepithelial Non-Muscle Invasive Bladder Cancer Following Transurethral Resection: A Case Report

Transurethral resection (TUR) is the gold standard treatment of non-muscle invasive bladder cancers. Recurrence occurs in approximately half of the patients with bladder cancer after initial TUR. Most recurrent bladder cancers present as polypoid masses with intraluminal growth originating from the mucosa. To the best of our knowledge, there has been no report on imaging findings of recurrent bladder cancers located within the subepithelial and intramural layers. Recurrent cancers within the intramural layer are difficult to detect with cystoscopy; they are also difficult to remove surgically. Imaging studies reveal the most important indicators for diagnosing subepithelial recurrent cancers. Here, we present a rare case of a recurrent bladder cancer within the subepithelial layer detected on imaging.

Holmium Laser En-bloc Resection Versus Conventional Transurethral Resection of Bladder Tumors for Treatment of Non-muscle-invasive Bladder Cancer: A Randomized Clinical Trial

BACKGROUND

En-bloc resection of bladder tumors achieves complete tumor removal, improves the quality of resection, decreases perioperative complication, and potentially improves recurrence rates.

OBJECTIVE

To assess the efficacy and safety of holmium laser en-bloc resection (HolERBT) versus conventional transurethral resection of bladder tumor (cTURBT).

DESIGN, SETTING, AND PARTICIPANTS

Between September 2015 and September 2018, 100 patients with non-muscle-invasive bladder cancer were randomly allocated to cTURBT or HolERBT.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was detection of residual tumor in reTURBT specimens at 4 wk after the primary resection. Operative parameters, specimen quality, perioperative complications, and recurrence-free survival (RFS) were compared. Independent sample t tests, χ² tests, and Kaplan-Meier curves were used, as appropriate.

RESULTS AND LIMITATIONS

The patient and tumor baseline characteristics were comparable between the groups. Residual tumors were detected in 7% and 27.7% of cases after HolERBT and cTURBT, respectively (p=0.01). Detrusor muscle was sampled in 98% of HolERBT and 62% of cTURBT cases (p<0.001). Lamina propria invasion substaging was feasible in only 68.2% of HolERBT and 18.4% of cTURBT cases (p<0.001). Following HolERBT, catheterization time (p<0.001) and hospital stay (p=0.001) were shorter when compared to cTURBT. Immediate postoperative instillation of chemotherapy in indicated cases was feasible for 100% of the HolERBT group and 91.5% of the cTURBT group (p=0.04). After follow-up of 20 ± 9.9 mo (13-36), RFS was 31.76 mo (95% confidence interval [CI] 28.67-34.86) in the HolERBT group and 28.25 mo (95% CI 24.87-31.64) in the cTURBT group (hazard ratio 0.43, 95% CI 0.17-1.1; p=0.07). However, this study was not powered to detect a difference in RFS.

CONCLUSIONS

Compared to cTURBT, HolERBT is a safer procedure for bladder tumor resection. It fulfills the oncological criteria of optimized resection with less residual tumor and better specimen quality.

PATIENT SUMMARY

En-bloc resection of bladder cancer tumors using a holmium laser is safer than the conventional technique. It has the advantages of less residual tumor and better specimen quality, with a similar tumor recurrence rate. This study is registered at ClinicalTrials.gov as NCT02555163.

En bloc resection of bladder tumors: indications, techniques, and future directions

PURPOSE OF REVIEW

En bloc resection of bladder tumor (ERBT) is an innovative new surgical technique, the use of which is becoming increasingly widespread. In this review, we analyze the recent literature and explore new developments, which may impact the future role of en bloc bladder surgery.

RECENT FINDINGS

ERBT increases the frequency with which detrusor muscle is present in the specimen (to 95%) and offers a significant improvement in the quality of the resection specimen, thereby helping with T1 substaging. Furthermore, the laser treatment reduces the rate of obturator nerve-related bladder perforation.

SUMMARY

ERBT represents a considerable advancement in the surgical management of nonmuscle-invasive bladder cancer. It delivers excellent oncological results and is a well tolerated procedure.

VIDEO

In the accompanying video, we shortly report the different modalities and energy sources used for bladder cancer resection. The three strategies are currently employed at the Fundació Puigvert (Barcelona). VIDEO ABSTRACT:.

Preoperative detection of Vesical Imaging-Reporting and Data System (VI-RADS) score 5 reliably identifies extravesical extension of urothelial carcinoma of the urinary bladder and predicts significant delayed time to cystectomy: time to reconsider the need for primary deep transurethral resection of bladder tumour in cases of locally advanced disease?

OBJECTIVES

(I) To determine Vesical Imaging-Reporting and Data System (VI-RADS) score 5 accuracy in predicting locally advanced bladder cancer (BCa), so as to potentially identify those patients who could avoid the morbidity of deep transurethral resection of bladder tumour (TURBT) in favour of histological sampling-TUR prior to radical cystectomy (RC). (II) To explore the predictive value of VI-RADS score 5 on time-to-cystectomy (TTC) outcomes.

PATIENTS AND METHODS

We retrospectively reviewed patients' ineligible or refusing cisplatin-based combination neoadjuvant chemotherapy who underwent multiparametric magnetic resonance imaging (mpMRI) of the bladder prior to staging TURBT followed by RC for muscle-invasive BCa. Sensitivity, specificity, positive and negative predictive values (PPV, NPV) were calculated for VI-RADS score 5 vs. score 2-4 cases to assess the accuracy of mpMRI for extravesical BCa detection (≥pT3). VI-RADS score performance was assessed by receiver operating characteristics curve analysis. A Κ statistic was calculated to estimate mpMRI and pathological diagnostic agreement. The risk of delayed TTC (i.e. time from initial BCa diagnosis of >3 months) was assessed using multivariable logistic regression model.

RESULTS

A total of 149 T2-T4a, cN0-M0 patients (VI-RADS score 5, n = 39 vs VI-RADS score 2-4, n = 110) were examined. VI-RADS score 5 demonstrated sensitivity, specificity, PPV and NPV, in detecting extravesical disease of 90.2% (95% confidence interval [CI] 84-94.3), 98.1% (95% CI 94-99.6), 94.9% (95% CI 89.6-97.6) and 96.4% (95% CI 91.6-98.6), respectively. The area under the curve was 94.2% (95% CI 88.7-99.7) and inter-reader agreement was excellent (Κ_inter 0.89). The mean (SD) TTC was 4.2 (2.3) and 2.8 (1.1) months for score 5 vs 2-4, respectively (P < 0.001). VI-RADS score 5 was found to independently increase risk of delayed TTC (odds ratio 2.81, 95% CI 1.20-6.62).

CONCLUSION

The VI-RADS is valid and reliable in differentiating patients with extravesical disease from those with muscle-confined BCa before TURBT. Detection of VI-RADS score 5 was found to predict significant delay in TTC independently from other clinicopathological features. In the future, higher VI-RADS scores could potentially avoid the morbidity of extensive primary resections in favour of sampling-TUR for histology. Further prospective, larger, and multi-institutional trials are required to validate clinical applicability of our findings.

Transurethral en bloc submucosal hydrodissection vs conventional resection for resection of non-muscle-invasive bladder cancer (HYBRIDBLUE): a randomised, multicentre trial

OBJECTIVE

To determine whether transurethral en bloc submucosal hydrodissection of bladder tumours (TUEB) improves the quality of the resection compared to conventional transurethral resection of bladder tumour (TURBT) in patients with non-muscle-invasive bladder cancer (NMIBC).

PATIENTS AND METHODS

A randomised, multicentre trial (HYBRIDBLUE) was conducted with a superiority design. Six German academic centres participated between September 2012 and August 2015. Based on literature analysis, a sample size for accurate histopathological assessment concerning muscle invasion was assumed to be feasible in 50% (P₀ = 0.5) of TURBT and 80% of TUEB cases. After pre-screening of a total of 305 patients, participants were allocated to two study arms: Group I: hexaminolevulinate (HAL)-guided TUEB; Group II: conventional HAL-guided TURBT. The primary endpoint was the proportion of specimens that could be reliably evaluated pathologically concerning muscle invasiveness. Secondary endpoints included rates of histopathological completeness of the resection, muscularis propria content, recurrence, and complication rates.

RESULTS

A total of 115 patients (TUEB 56; TURBT 59) were eligible for final analysis. Adequate histopathological assessment, which included muscularis propria content and tumour margins (R0 vs R1), was present in 48/56 (86%) TUEB patients compared to 37/59 (63%; P = 0.006) in the TURBT group. R0 was confirmed in 30/56 TUEB patients (57%) and five of 59 TURBT patients (9%; P < 0.001). No complications of Grade ≥III were observed in both arms. At 3 and 12 months, three and 19 patients recurred in the TUEB group vs seven and 11 patients in the TURBT group, respectively (P = 0.33 and P = 0.08).

CONCLUSIONS

In this randomised study, TUEB was shown to be clinically safe regarding perioperative endpoints. An adequate histopathological assessment concerning muscle invasion was significantly better assessable in the TUEB arm compared to standard TURBT. This finding indicates the clinical potential for reducing the rate of early re-resections. Yet, a larger study with recurrence-free survival as the primary endpoint is needed to assess the oncological efficacy between both techniques.

The Clinical Application and Potential Roles of Circulating Tumor Cells in Bladder Cancer and Prostate Cancer

Circulating tumor cells (CTCs) are considered to be promising biomarkers in malignant diseases. Recently, molecular profiles of CTCs in prostate cancer (PCa) and the role of CTCs in neoadjuvant chemotherapy and transurethral resections of bladder cancer (BCa) are intensely studied. However, localized PCa and nonmuscle-invasive BCa are less investigated and discussed. Moreover, the benefit and feasibility of clinical applications of CTCs should be critically questioned and reevaluated. This review focuses mainly on clinical issues and lesser on methodologies, and summarizes the quintessence of available works dealing with clinical applications of CTCs in PCa and BCa management.

En-bloc resection of urinary bladder tumour - a prospective controlled multicentre observational study

Introduction

Transurethral resection of bladder tumour (TURBT) is one of the most commonly performed urologic procedures. Because of the shortcomings of conventional TURBT, the en-bloc resection concept was created.

Aim

To analyse the influence of en-bloc technique on surgical and oncological outcomes of TURBT performed with electric current.

Material and methods

This non-randomized, prospective controlled multicentre study enrolled 427 consecutive patients undergoing TURBT performed by five experienced endourologists in five academic institutions. Choice of procedure was at the discretion of the surgeon. The vast majority of patients underwent monopolar resection. The en-bloc procedure was performed with Collin's knife or the classic resection loop. Study end-points were surgery, catheterization and hospitalization time, presence of muscularis propria (MP) in the specimen and 3-month recurrence-free survival (RFS).

Results

The study included 427 (274 conventional TURBT vs. 153 en-bloc) patients with mean age of 69 years (range: 18-99). There were more cases with MP present in the specimen in the en-bloc group (91.3% vs. 75.5%; p < 0.001). Surgery and hospitalization times were statistically shorter in the en-bloc group (both p < 0.05). A borderline significant difference was noted when the number of residual tumours in reTURBTs was analysed, with fewer cases of residual tumour in the en-bloc group (p = 0.051). RFS at 3 months was higher in the en-bloc group (88.4% vs. 80.1%; p = 0.027). After propensity score matching, differences in MP presence, hospitalization time and 3-month RFS status remained statistically significant.

Conclusions

When compared to conventional TURBT, en-bloc resection of bladder tumour is associated with higher percentage of MP presence in histopathological specimen, higher 3-month RFS and shorter hospitalization time.

Retrograde en bloc resection for non-muscle invasive bladder tumor can reduce the risk of seeding cancer cells into the peripheral circulation

Objective

To ascertain whether en bloc resection could reduce the risk of seeding cancer cells into the circulation during the resection of non-muscle invasive bladder cancer (NMIBC).

Methods

Patients with primary NMIBC were enrolled in this prospective study from October 2017 to May 2018. Patients were allocated to receive conventional transurethral resection of the bladder (TURB) or retrograde en bloc resection technique of the bladder tumor (RERBT). Blood samples (1 ml) for circulating tumor cell (CTC) enumeration were drawn from the peripheral vein prior to resection (PV1), immediately after resection of the tumor base (PV2), and at 12 h after resection (PV3). Intra-group comparisons of the changes in the number of CTCs identified among the PV1, PV2, and PV3 blood samples were performed in each group.

Results

A total of 21 patients (12 in the RERBT group and 9 in the TURB group) were recruited. For patients receiving TURB, the level of CTCs identified in PV3 was significantly higher than that in PV1 (p = 0.047). However, there was no significant difference in CTC counts before and after resection in the RERBT group.

Conclusion

RERBT did not increase the number of tumor cells in the bloodstream.

Management of Muscle-invasive Bladder Cancer in the 2020s: Challenges and Perspectives

Despite an increased use of neoadjuvant and adjuvant chemotherapy, the long-term survival rates after radical cystectomy or trimodal therapy (TMT) for muscle-invasive bladder cancer (MIBC) remain basically unchanged for decades. Detection and effective treatment of micrometastatic disease are still a clinical dilemma. Assessment of circulating tumor DNA in combination with improved imaging modalities may improve the prediction of micrometastatic disease. Different genetic subtypes of MIBC show varying degrees of chemosensitivity. Further progress needs to be made in order to develop a common molecular classifier that can be used easily for daily clinical decision making. With the advent on immuno-oncology, bladder-sparing protocols are on the rise as an alternative to surgery. The extent of transurethral bladder tumor resection has a marked impact on the response rates to TMT and neoadjuvant chemotherapy. This review focuses on strategies regarding how to integrate surgery, radiotherapy, and molecular-based systemic treatment for improved oncological outcomes of patients with MIBC. PATIENT SUMMARY: Effective treatment of micrometastatic disease is the key to improved oncological outcomes in muscle-invasive bladder cancer and requires a multidisciplinary approach.

Safety and efficacy of en bloc transurethral resection versus conventional transurethral resection for primary nonmuscle-invasive bladder cancer: a meta-analysis

Background

The purpose of this meta-analysis is to compare the safety and efficacy of en bloc transurethral resection of bladder tumor (EBRT) versus conventional transurethral resection of bladder tumor (CTURBT).

Methods

We performed a meta-analysis of relevant articles through November 2019 using PubMed, Embase, and Cochrane Central Register to compare the safety and efficacy of EBRT versus CTURBT. The main endpoint included the operation time (OT), hospitalization time (HT), catheterization time (AT), perioperative period complications, bladder detrusor muscle found in the specimen, the residual tumor on the base, the ratio of the same site recurrence, and 12/24/36-month recurrence rate. Cochrane Collaboration’s Revman software, version 5.3, was used for statistical analysis.

Results

A total of 19 studies with 2651 patients were included, 1369 underwent EBRT and 1282 underwent CTURBT. Patients treated with EBRT had a significantly lower AT, HT, obturator nerve reflex, bladder perforation, bladder irritation, postoperative complications, and 24-month recurrence rate than those who underwent CTURBT. While no significant difference was found in terms of OT, the ratio of bladder detrusor muscle found in the specimen, the residual tumor on the base, 12-month recurrence rate, 36-month recurrence rate, and the ratio of the same site recurrence. In mitomycin subgroup, EBRT was superior to CTURBT in terms of 12/24-month recurrence rate. Similarly, in the prospective subgroup and retrospective subgroup, EBRT had a lower 24-month recurrence rate than CTURBT. However, no significant difference was found in the low, intermediate, and high-risk group in the light of 12–36-month recurrence rate.

Conclusions

Based on the included 19 articles, EBRT had a significantly lower AT, HT, intraoperative and postoperative complications, and 24-month recurrence rate than those treated with CTURBT. Well-designed randomized controlled trials were needed to reevaluate these outcomes.

Trial registration

This meta-analysis was reported in agreement with the PRISMA statement and was registered on PROSPERO 2019 CRD42019121673.

Perioperative Detection of Circulating Tumor Cells in Radical or Partial Nephrectomy for Renal Cell Carcinoma

BACKGROUND

The current study was conducted to clarify the frequency of systemic circulating tumor cells (CTCs) appearing after surgery for renal cell carcinoma and to evaluate the differences in postoperative CTCs between different surgical procedures.

METHODS

This prospective, cohort study included 60 consecutive patients who underwent laparoscopic radical nephrectomy (RN) (n = 22), laparoscopic partial nephrectomy (PN) (n = 19), open RN (n = 8), or open PN (n = 11). In this study CTCs were measured by the FISHMAN-R system, and CTCs drawn from a peripheral artery were collected just before and immediately after surgery. The number of pre- and postoperative CTCs and the perioperative changes in CTCs were measured for each surgical method.

RESULTS

Six patients were excluded from the current analyses. Preoperative CTCs did not differ significantly by surgical approach (laparoscopic RN: 3.4 ± 4.2; laparoscopic PN: 3.4 ± 4.1; open RN: 7.7 ± 6.8; open PN: 6.0 ± 7.6; P = 0.19). Open RN resulted in a significantly greater number of postoperative CTCs (laparoscopic RN: 4.8 ± 3.7; laparoscopic PN: 7.9 ± 9.1; open RN: 22.5 ± 26.3; open PN: 6.4 ± 6.3; P < 0.001) and perioperative changes in CTCs (laparoscopic RN: 1.3 ± 5.3; laparoscopic PN: 4.5 ± 9.6; open RN: 14.7 ± 25.0; open PN: 0.4 ± 6.3; P < 0.001). No significant differences in these were observed among the three groups except in the open RN group. In the multivariate analysis, the surgical approach was significantly correlated with the number of postoperative CTCs (P = 0.016) and the perioperative change in CTCs (P = 0.01).

CONCLUSIONS

This proof-of-concept study indicated that after surgery, more cancer cells can be expelled into the bloodstream, especially after open RN. Sufficient and careful follow-up assessment for the emergence of distant metastases is needed for patients undergoing open RN.

Accurate Quantification of Residual Cancer Cells in Pelvic Washing Reveals Association with Cancer Recurrence Following Robot-Assisted Radical Cystectomy

PURPOSE

Bladder cancer recurrence following cystectomy remains a significant cause of bladder cancer specific mortality. Residual cancer cells contribute to cancer recurrence due to tumor spillage or undetectable preexisting micrometastatic tumor clones. We detected and quantified residual cancer cells in pelvic washing using ultradeep targeted sequencing. We compared the levels of residual cancer cells with clinical variables and cancer recurrence.

MATERIALS AND METHODS

The primary tumor specimen was available in 17 patients who underwent robot-assisted radical cystectomy. All tumors had negative surgical margins. Pelvic washes and blood were collected intraoperatively before and after robot-assisted radical cystectomy, after pelvic lymph node dissection and in the suction fluid collected during the procedure. Two-step sequencing, including whole exome sequencing followed by ultradeep targeted sequencing (× greater than 50,000), was done to quantify residual cancer cells in each sample. Eight patients were excluded from study due to sample quality issues. The final analysis cohort comprised 9 patients. The residual cancer cell level was quantified for each sample as the relative cancer cell fraction and compared between time points. The peak relative cancer cell fraction of each patient was correlated with clinical and pathological variables.

RESULTS

Residual cancer cells were detected in approximately half of the pelvic washing specimens during or after but not before robot-assisted radical cystectomy. Higher residual cancer cell levels were associated with aggressive variant histology and cancer recurrence. Verifying the feasibility of using residual cancer cells as a novel biomarker for recurrence requires larger cohorts.

CONCLUSIONS

Detection of residual cancer cells in intraoperative peritoneal washes of patients with bladder cancer who undergo radical cystectomy may represent a robust biomarker of tumor aggressiveness and metastatic potential.