Differences in the recurrence pattern after neoadjuvant chemotherapy compared to surgery alone in patients with muscle-invasive bladder cancer

Impact of Urethra-Preserving Surgery During Radical Cystectomy: An Optimal Urethral Management in the Robotic Era

OBJECTIVES

The optimal indication and survival benefits of prophylactic urethrectomy (PU) during radical cystectomy remain unclear. Therefore, this study aims to evaluate the impact of urethra-preserving surgery (UPS) on oncological outcome including its recurrence patterns, and to establish an optimal urethral management strategy with a novel UPS technique in the robotic era.

PATIENTS AND METHODS

We retrospectively analyzed 281 male patients with bladder cancer who received radical cystectomy (RC) (115 with and 166 without PU) at our institutions between 2010 and 2023. Subsequently, perioperative and oncological outcomes were assessed between propensity score-matched cohorts.

RESULTS

Urethral recurrence (UR) occurred in 5 patients (5/166, 3.0%), all of whom underwent open-RC. Three among those (1.8%) with concomitant metastasis were died of cancer. There were no statistically significant differences between the PU and UPS groups in urethral-recurrence free survival (urethral-RFS) (P = .14), local-RFS (P = .59) and overall survival (OS) (P = .84) in the entire cohort. However, the UPS group showed significantly worse urethral-RFS (P = .008), local-RFS (P = .005) and OS (P = .03) in patients with high-risk of UR. Analysis of recurrence patterns revealed that UPS in high-risk patients significantly increased local recurrence (25.8% vs. 5.0%, P = .02). Conversely, a novel robotic-UPS technique demonstrated significantly favorable perioperative outcomes, comparable local-RFS (P = .79) and OS (P = .16) without UR (0/134, 0%) when compared to robotic-PU. Robotic-UPS also exhibited significantly better local-RFS (P =.007) and OS (P < .001) than open-UPS.

CONCLUSIONS

UR-related death was rare and PU did not show a survival benefit for the entire cohort. However, inappropriate UPS in patients at high-risk of UR may increase local recurrence which might be responsible for poor survival after UPS rather than disease progression derived from UR. The robotic-UPS has the potential to reduce unnecessary PU, urethral and local recurrence without compromising survival.

Cost of bladder cancer in Lebanon before and after the economic collapse: a probabilistic modeling study

BACKGROUND AND OBJECTIVES

Lebanon has one of the highest incidence rates of bladder cancer (BC) in the world. In 2019, Lebanon's economy collapsed which majorly impacted healthcare costs and coverage. This study assesses the overall direct costs of urothelial BC in Lebanon, from the perspective of public and private third-party payers (TPP) and households, and evaluates the impact of the economic collapse on these costs.

METHODS

This was a quantitative, incidence-based cost-of-illness study, conducted using a macro-costing approach. Costs of medical procedures were obtained from the records of various TPPs and the Ministry of Public Health. We modeled the clinical management processes for each stage of BC, and conducted probabilistic sensitivity analyses to estimate and compare the cost of each stage, pre-and post-collapse, and for each payer category.

RESULTS

Before the collapse, the total annual cost of BC in Lebanon was estimated at LBP 19,676,494,000 (USD 13,117,662). Post-collapse, the total annual cost of BC in Lebanon increased by 768% and was estimated at LBP 170,727,187,000 (USD 7,422,921). TPP payments increased by 61% whereas out-of-pocket (OOP) payments increased by 2,745% resulting in a decrease in TPP coverage to only 17% of total costs.

CONCLUSION

Our study shows that BC in Lebanon constitutes a significant economic burden costing 0.32% of total health expenditures. The economic collapse induced an increase of 768% in the total annual cost, and a catastrophic increase in OOP payments.

IMvigor011: a study of adjuvant atezolizumab in patients with high-risk MIBC who are ctDNA+ post-surgery

The standard-of-care for muscle-invasive bladder cancer is radical surgery with neoadjuvant cisplatin-based chemotherapy. Despite curative intent from these interventions, relapse rates post-surgery remain high, with approximately 50% of patients developing local or distant recurrence within 2 years of surgery and a 5-year survival of only 50-60%. Identifying patients who are high risk for relapse post-surgery is a priority. Monitoring patients for circulating tumor DNA (ctDNA) is a minimally invasive approach that appears attractive for selecting patients potentially suitable for adjuvant treatment with checkpoint inhibitors. IMvigor011 (NCT04660344) is a global, double-blind, randomized phase III study assessing the efficacy of atezolizumab (anti-PD-L1) versus placebo in patients with high-risk muscle-invasive bladder cancer who are ctDNA positive post-cystectomy. The primary end point is disease-free survival in participants who are ctDNA positive within 20 weeks of cystectomy.

Inhibition of PP2A by LB100 sensitizes bladder cancer cells to chemotherapy by inducing p21 degradation

PURPOSE

Bladder carcinoma (BLCA) is the most common urinary tract malignancy and exhibits a poor response to chemotherapy. Protein phosphatase 2A (PP2A) is a serine/threonine phosphatase involved in a wide variety of regulatory cellular processes, including apoptosis and the DNA-damage response (DDR). LB100, a small molecule inhibitor of PP2A, has been shown to act as a chemo-sensitizer in multiple types of cancer. However, the anti-tumor effect and mode of action of LB100 in BLCA have yet to be identified.

METHODS

In vitro and in vivo experiments were performed to assess the anti-tumor effect of LB100 alone or in combination with gemcitabine. Mass spectrometry (MS)-based phosphoproteomics analysis was used to identify the downstream substrates of PP2A and to explore the mechanism underlying LB100-induced DNA damage and apoptosis. In addition, we established a chemo-resistant BLCA cell line (RT-112-R) by prolonged drug exposure and determined the effect of LB100 in enhancing genotoxicity in BLCA cell lines and xenograft mouse models.

RESULTS

We found that LB100 is sufficient to induce an anti-tumor response in BLCA cells by inducing DNA damage and apoptosis both in vitro and in vivo. Furthermore, we found that PP2A potentially dephosphorylates p-p21-ser130 to stabilize p21. Inhibition of PP2A by LB100 increased the level of p-p21-ser130, subsequently leading to a reduction in p21 level in a dose-dependent manner. In addition, we found that treatment of LB100 abrogated the G1/S cell cycle checkpoint, resulting in increased phosphorylation of γH2AX in BLCA cells. Moreover, LB100 enhanced genotoxicity in chemo-resistant BLCA cells by inducing DNA damage and apoptosis in vitro and in vivo.

CONCLUSION

Our findings indicate that PP2A may serve as a potential therapeutic target in BLCA through regulating p21 stability.

Significance of prophylactic urethrectomy at the time of radical cystectomy for bladder cancer

BACKGROUND

Prophylactic urethrectomy at the time of radical cystectomy is frequently recommended for patients with bladder cancer at a high risk of urethral recurrence without definitive evidence. The present study attempted to clarify the survival benefits of performing prophylactic urethrectomy.

METHODS

We identified 214 male patients who were treated by radical cystectomy with an incontinent urinary diversion in our seven institutions between 2004 and 2017. We used propensity score matching and ultimately identified 114 patients, 57 of whom underwent prophylactic urethrectomy (prophylactic urethrectomy group) and 57 who did not (non-prophylactic urethrectomy group).

RESULTS

No significant differences were observed in the 5-year overall survival rate between the prophylactic urethrectomy and non-prophylactic urethrectomy groups in the overall. However, the local recurrence rate was significantly lower in the prophylactic urethrectomy group than in the non-prophylactic urethrectomy group (P = 0.015). In the subgroup of 58 patients with multiple tumours and/or concomitant carcinoma in situ at the time of transurethral resection of bladder tumour, the 5-year overall survival rate was significantly higher in the prophylactic urethrectomy group than in the non-prophylactic urethrectomy group (P = 0.021). A multivariate analysis revealed that performing prophylactic urethrectomy was the only independent predictor of the overall survival rate (P = 0.016). In those patients who were treated without neoadjuvant chemotherapy (n = 38), the 5-year overall survival rate was significantly higher in the prophylactic urethrectomy group than in the non-prophylactic urethrectomy group (P = 0.007).

CONCLUSIONS

Prophylactic urethrectomy at the time of radical cystectomy may have a survival benefit in patients with multiple tumours and/or concomitant carcinoma in situ, particularly those who do not receive neoadjuvant chemotherapy.

A detailed analysis of the recurrence timing and pattern after curative surgery in patients undergoing neoadjuvant therapy or upfront surgery for gastric cancer

BACKGROUND AND OBJECTIVES

The aim of this study was to determine whether the administration of neoadjuvant therapy (NAD) affects the incidence, timing, and pattern of recurrence in patients treated by curative gastrectomy.

METHODS

Sixty-nine patients undergoing NAD and R0 gastrectomy were compared with 198 patients undergoing upfront surgery using the propensity score matching (PSM) method. Disease-free survival (DFS), disease-specific survival (DSS), and progression-free survival (PFS) analyses were conducted with a log-rank test and Cox regression. Risk factors for recurrence were assessed by logistic regression.

RESULTS

Among 69 patients with NAD, 28 (40.6%) experienced recurrence, and signet-ring cell (SRC) carcinoma was the only factor independently associated with recurrence. In the whole sample, NAD did not influence DFS, DSS, rate of recurrence, or PFS. After PSM, the variables associated with DFS were cN1, type of gastrectomy, the presence of SRCs, and the presence of lymphovascular invasion. Variables independently associated with recurrence were cN1, type of gastrectomy, and the presence of SRCs.

CONCLUSIONS

NAD had no impact on DFS, DSS, or the pattern of recurrence in any patients with gastric cancer. To define a better treatment strategy, future studies should focus on subtypes that do not respond to the current neoadjuvant regimens.

Early Detection of Metastatic Relapse and Monitoring of Therapeutic Efficacy by Ultra-Deep Sequencing of Plasma Cell-Free DNA in Patients With Urothelial Bladder Carcinoma

PURPOSE

Novel sensitive methods for early detection of relapse and for monitoring therapeutic efficacy may have a huge impact on risk stratification, treatment, and ultimately outcome for patients with bladder cancer. We addressed the prognostic and predictive impact of ultra-deep sequencing of cell-free DNA in patients before and after cystectomy and during chemotherapy.

PATIENTS AND METHODS

We included 68 patients with localized advanced bladder cancer. Patient-specific somatic mutations, identified by whole-exome sequencing, were used to assess circulating tumor DNA (ctDNA) by ultra-deep sequencing (median, 105,000×) of plasma DNA. Plasma samples (n = 656) were procured at diagnosis, during chemotherapy, before cystectomy, and during surveillance. Expression profiling was performed for tumor subtype and immune signature analyses.

RESULTS

Presence of ctDNA was highly prognostic at diagnosis before chemotherapy (hazard ratio, 29.1; P = .001). After cystectomy, ctDNA analysis correctly identified all patients with metastatic relapse during disease monitoring (100% sensitivity, 98% specificity). A median lead time over radiographic imaging of 96 days was observed. In addition, for high-risk patients (ctDNA positive before or during treatment), the dynamics of ctDNA during chemotherapy was associated with disease recurrence (P = .023), whereas pathologic downstaging was not. Analysis of tumor-centric biomarkers showed that mutational processes (signature 5) were associated with pathologic downstaging (P = .024); however, no significant correlation for tumor subtypes, DNA damage response mutations, and other biomarkers was observed. Our results suggest that ctDNA analysis is better associated with treatment efficacy compared with other available methods.

CONCLUSION

ctDNA assessment for early risk stratification, therapy monitoring, and early relapse detection in bladder cancer is feasible and provides a basis for clinical studies that evaluate early therapeutic interventions.

Low-dose Bacillus Calmette-Guerin versus full-dose for intermediate and high-risk of non-muscle invasive bladder cancer: a Markov model

BACKGROUND

To compare the efficacy of low dose (27 mg) Bacillus Calmette-Guérin (BCG) and a full dose (81 mg) BCG immunotherapy for patients with intermediate and high-risk non-muscle invasive bladder cancer (NMIBC) after a typical transurethral bladder resection.

METHODS

We constructed a Markov model for a 20-year simulation of the disease to compare the overall survival of patients with intermediate and high-risk of NMIBC between the full-dose therapy (FD group) and the low-dose therapy (LD group). Base case analysis, one-way and two-way sensitivity analysis and a second-order Monte Carlo analysis were performed based on data from 15 published articles.

RESULTS

The expected overall survivals were 9.56 (9.55-9.57) years for FD group and 9.63 (9.61-9.64) years for LD group(P < 0.001). The estimated mortality in the FD group at 5, 10, and 20 years were 34.23%, 57.51% and 83.14%, respectively. The corresponding values in the LD group were 34.11%, 57.17%, 82.16%, respectively. Age-specific mortality and metastatic rate after undergoing radical cystectomy (RC) were the most two sensitive parameters in both groups. The rate of disease recurrence with disease worsening is the determining factor when choosing the optimal dose of BCG treatment.

CONCLUSIONS

A low-dose BCG treatment may act slightly better than a full-dose BCG treatment for patients with intermediate and high-risk of NMIBC. This finding will require further high-quality studies to validate.

Association Of Plasma And Urinary Mutant DNA With Clinical Outcomes In Muscle Invasive Bladder Cancer

Muscle Invasive Bladder Cancer (MIBC) has a poor prognosis. Whilst patients can achieve a 6% improvement in overall survival with Neo-Adjuvant Chemotherapy (NAC), many do not respond. Body fluid mutant DNA (mutDNA) may allow non-invasive identification of treatment failure. We collected 248 liquid biopsy samples including plasma, cell pellet (UCP) and supernatant (USN) from spun urine, from 17 patients undergoing NAC. We assessed single nucleotide variants and copy number alterations in mutDNA using Tagged-Amplicon- and shallow Whole Genome- Sequencing. MutDNA was detected in 35.3%, 47.1% and 52.9% of pre-NAC plasma, UCP and USN samples respectively, and urine samples contained higher levels of mutDNA (p = <0.001). Longitudinal mutDNA demonstrated tumour evolution under the selective pressure of NAC e.g. in one case, urine analysis tracked two distinct clones with contrasting treatment sensitivity. Of note, persistence of mutDNA detection during NAC predicted disease recurrence (p = 0.003), emphasising its potential as an early biomarker for chemotherapy response.