Accuracy of Frozen Section Analysis of Urethral and Ureteral Margins During Radical Cystectomy for Bladder Cancer: A Systematic Review and Diagnostic Meta-Analysis

Virtual Staining of Nonfixed Tissue Histology

Surgical pathology workflow involves multiple labor-intensive steps, such as tissue removal, fixation, embedding, sectioning, staining, and microscopic examination. This process is time-consuming and costly and requires skilled technicians. In certain clinical scenarios, such as intraoperative consultations, there is a need for faster histologic evaluation to provide real-time surgical guidance. Currently, frozen section techniques involving hematoxylin and eosin (H&E) staining are used for intraoperative pathology consultations. However, these techniques have limitations, including a turnaround time of 20 to 30 minutes, staining artifacts, and potential tissue loss, negatively impacting accurate diagnosis. To address these challenges, researchers are exploring alternative optical imaging modalities for rapid microscopic tissue imaging. These modalities differ in optical characteristics, tissue preparation requirements, imaging equipment, and output image quality and format. Some of these imaging methods have been combined with computational algorithms to generate H&E-like images, which could greatly facilitate their adoption by pathologists. Here, we provide a comprehensive, organ-specific review of the latest advancements in emerging imaging modalities applied to nonfixed human tissue. We focused on studies that generated H&E-like images evaluated by pathologists. By presenting up-to-date research progress and clinical utility, this review serves as a valuable resource for scholars and clinicians, covering some of the major technical developments in this rapidly evolving field. It also offers insights into the potential benefits and drawbacks of alternative imaging modalities and their implications for improving patient care.

Electrospun nanofibrous mats loaded with gemcitabine and cisplatin suppress bladder tumor growth by improving the tumor immune microenvironment

The perplexing issues related to positive surgical margins and the considerable negative consequences associated with systemic chemotherapy have posed ongoing challenges for clinicians, especially when it comes to addressing bladder cancer treatment. The current investigation describes the production of nanocomposites loaded with gemcitabine (GEM) and cisplatin (CDDP) through the utilization of electrospinning technology. In vitro and in vivo studies have provided evidence of the strong effectiveness in suppressing tumor advancement while simultaneously reducing the accumulation of chemotherapy drugs within liver and kidney tissues. Mechanically, the GEM and CDDP-loaded electrospun nanocomposites could effectively eliminate myeloid-derived suppressor cells (MDSCs) in tumor tissues, and recruit CD8+ T cells and NKp46+ NK cells to kill tumor cells, which can also effectively inhibit tumor microvascular formation. Our investigation into the impact of localized administration of chemotherapy through GEM and CDDP-loaded electrospun nanocomposites on the tumor microenvironment will offer novel insights for tackling tumors.

The impact of routine frozen section analysis during nephroureterectomy or segmental ureterectomy for urothelial carcinoma on final surgical margin status and long-term oncologic outcome

OBJECTIVE

The utility of intraoperative frozen section analysis (FSA) at the surgical margins (SMs) in patients with upper urinary tract cancer has not been established. We herein assessed the clinical significance of routine FSA of ureteral SMs during nephroureterectomy (NU) or segmental ureterectomy (SU).

MATERIALS AND METHODS

A retrospective review of our Surgical Pathology database identified consecutive patients undergoing NU (n=246) or SU (n=42) for urothelial carcinoma from 2004 to 2018. FSA (n=54) was correlated with the diagnosis of frozen section controls, the status of final SMs, and the prognosis of patients.

RESULTS

During NU, FSA was performed in 19 (7.7%) patients and was significantly more often requested in cases with ureteral tumor (13.1%) than in those with renal pelvis/calyx tumor (3.5%). Final SMs at the distal ureter/bladder cuff were positive only in non-FSA cases in the entire NU cohort (8.4%; P=0.375) or those with tumor at the lower ureter (57.6%; P=0.046), but not in any of FSA patients (0%). During SU, FSA was performed in 35 (83.3%) cases, including 19 at either proximal or distal SM and 16 at both SMs (SU-FSA2). Final positive SMs were significantly more often detected in non-FSA patients (42.9%) than in all FSA (8.6%; P=0.048) or SU-FSA2 (0%; P=0.020) patients. Overall, FSAs were reported as positive or high-grade carcinoma (n=7), atypical or dysplasia (n=13), and negative (n=34), and all these diagnoses were confirmed accurate on the frozen section controls, except one with a revision from atypical to carcinoma in situ. Meanwhile, 16 (80.0%) of 20 cases with initial positive/atypical FSA achieved negative conversion by excision of additional tissue. Kaplan-Meier analysis revealed that SU-FSA did not significantly reduce the risk of tumor recurrence in the bladder, disease progression, or cancer-specific mortality. Nonetheless, NU-FSA was strongly associated with reduced progression-free (P=0.023) and cancer-specific (P=0.007) survival rates, compared with non-FSA, which may imply a selection bias (e.g., FSA for clinically more aggressive tumors).

CONCLUSIONS

Performing FSA during NU for lower ureteral tumor, as well as during SU, significantly reduced the risk of positive SMs. However, routine FSA for upper urinary tract cancer failed to considerably improve long-term oncologic outcome.

Real-Time Urethral and Ureteral Assessment during Radical Cystectomy Using Ex-Vivo Optical Imaging: A Novel Technique for the Evaluation of Fresh Unfixed Surgical Margins

Background: Our study aims to assess the feasibility and the reproducibility of fluorescent confocal microscopy (FCM) real-time assessment of urethral and ureteral margins during open radical cystectomy (ORC) for bladder cancer (BCa). Methods: From May 2020 to January 2022, 46 patients underwent ORC with intraoperative FCM evaluation. Each specimen was intraoperatively stained for histopathological analysis using FCM, analyzed as a frozen section (FSA), and sent for traditional H&E examination. Sensitivity, specificity, positive predictive value (PPV), and the negative predictive value (NPV) of FCM and FSA were assessed and compared with H&E for urethral and ureteral margins separately. Results: The agreement was evaluated through Cohen’s κ statistic. Urethral diagnostic agreement between FCM and FSA showed a κ = 0.776 (p < 0.001), while between FCM and H&E, the agreement was κ = 0.691 (p < 0.001). With regard to ureteral margins, an overall agreement of κ = 0.712 (p < 0.001) between FCM and FSA and of κ = 0.481 (p < 0.001) between FCM and H&E was found. Conclusions: FCM proved to be a safe, feasible, and reproducible method for the intraoperative assessment of urethral and ureteral margins during ORC. Compared to standard FSA, FCM showed adequate diagnostic performance in detecting urethral and ureteral malignant involvement.

A Systematic Review and Meta-Analysis of Clinicopathologic Factors Predicting Upper Urinary Tract Recurrence After Radical Cystectomy for Urothelial Bladder Cancer

To identify risk factors for upper urinary tract recurrence (UUTR) in patients treated with radical cystectomy (RC) for urothelial bladder carcinoma (UBC). The PubMed, Web of Science, and Cochrane Library were searched on March 2022 to identify relevant studies according to the Preferred Reporting Items for Systematic Review (PRISMA) statement. We included studies that provided multivariate logistic regression analyses. The pooled UUTR rate was calculated using a fixed effect model. We identified 235 papers, of which seven and 6 articles, comprising a total of 8981 and 8404 UBC patients, were selected for qualitative and quantitative analyses, respectively. Overall, 418 (4.65%) patients were diagnosed with UUTR within a median time of 1.4 to 3.1 years after RC. Risk factors for UUTR were surgical margin (hazard ratio [HR] 3.41, 95% confidence interval [CI] 2.59-4.49, P < .00001), preoperative hydronephrosis (HR: 1.74, 95% CI: 1.25-2.43, P = .001), ureteral margin (HR: 4.34, 95% CI: 2.75-6.85, P < .00001), and pT stage (HR: 2.69, 95% CI: 1.37-5.27, P < .004). Incorporation of established risk factors into a clinical prediction model might aid in the decision-making process regarding the intensity and type of surveillance protocols after RC as well as help determine the pretest probability of UUTR.

Follow-up of the Urethra and Management of Urethral Recurrence After Radical Cystectomy: A Systematic Review and Proposal of Management Algorithm by the European Association of Urology-Young Academic Urologists: Urothelial Carcinoma Working Group

CONTEXT

Surveillance of the urethra and management of urethral recurrence (UR) after radical cystectomy (RC) is an area with poor evidence.

OBJECTIVE

We aimed to summarize the available evidence and provide clinicians with practical recommendations on how to prevent and manage UR after RC for bladder cancer.

EVIDENCE ACQUISITION

The MEDLINE and EMBASE databases were searched during September 2021 for studies evaluating UR after RC. The primary endpoint was oncologic outcomes for patients who experienced UR depending on different surveillance and management approaches.

EVIDENCE SYNTHESIS

Forty-three studies were included in the quantitative synthesis. According to the currently available literature, a tight-knitted surveillance protocol should be implemented for males treated with RC and nonorthotopic neobladder diversion as well as patients with prostatic involvement, tumor multifocality, bladder neck involvement, and concomitant carcinoma in situ. A survival benefit of a prophylactic urethrectomy has been reported only in patients at very high risk for UR based on clinical factors. Surveillance protocols were highly heterogeneous and poorly documented among included studies. Patients whose UR was diagnosed based on clinical symptoms had a poor prognosis. Only limited data were available on the comparative effectiveness of watchful waiting after RC versus clinical symptom screening as part of a follow-up strategy. However, the use of regular cytology and/or urethroscopy seems useful in select patients at high risk for UR. Despite limited data on the optimal management of UR, urethra-sparing approaches (transurethral resection of UR) seem to be an option for Ta (only) recurrences; a salvage urethrectomy with or without chemotherapy should be the standard for all others.

CONCLUSIONS

Based on the currently available literature, we have proposed an algorithm to guide the decision-making process to help identify and treat UR after RC. Given the lack of evidence on how to deal with UR and surveil patients at risk for UR, this study may invigorate research in this area of unmet need.

PATIENT SUMMARY

Early diagnosis and tailored management of urethral recurrence could help improve oncologic outcomes in these patients.

Urethrectomy at the time of radical cystectomy for non-metastatic urothelial carcinoma of the bladder: a collaborative multicenter study

INTRODUCTION

The optimal management of the urethra in patients planned for radical cystectomy (RC) remains unclear. We sought to evaluate the impact of urethrectomy on perioperative and oncological outcomes in patients treated with RC for non-metastatic urothelial carcinoma of the bladder (UCB).

MATERIALS AND METHODS

We assessed the retrospective data from patients treated with RC for UCB of five European University Hospitals. Associations of urethrectomy with progression-free (PFS), cancer-free (CSS), and overall (OS) survivals were assessed in univariable and multivariable Cox regression models. We performed a subgroup analysis in patients at high risk for urethral recurrence (UR) (urethral invasion and/or bladder neck invasion and/or multifocality and/or prostatic urethra involvement).

RESULTS

A total of 887 non-metastatic UCB patients were included. Among them, 146 patients underwent urethrectomy at the time of RC. Urethrectomy was performed more often in patients with urethral invasion, T3/4 tumor stage, CIS, positive frozen section analysis of the urethra, and those who received neoadjuvant chemotherapy, underwent robotic RC, and/or received an ileal conduit urinary diversion (all p < 0.001). Estimated blood loss and the postoperative complication rate were comparable between patients who received an urethrectomy and those who did not. Urethrectomy during RC was not associated with PFS (HR 0.83, p = 0.17), CSS (HR 0.93, p = 0.67), or OS (HR 1.08, p = 0.58). In the subgroup of 276 patients at high risk for UR, urethrectomy at the time of RC decreased the risk of progression (HR 0.58, p = 0.04).

CONCLUSION

In our study, urethrectomy at the time of RC seems to benefit only patients at high risk for UR. Adequate risk assessment of UCB patients' history may allow for better clinical decision-making and patient counseling.