Radical cystectomy and lymphadenectomy for invasive bladder cancer: towards the evolution of an optimal surgical standard

Prognostic Significance of Lymph Node Density in Pathological Node Positive Urothelial Carcinoma of the Bladder -Upfront Surgery and Post Neoadjuvant Chemotherapy Cohorts

AIM

To validate the role of lymph node density as a prognostic marker in patients undergoing primary surgery and postneoadjuvant therapy in pathological node-positive urothelial bladder carcinoma.

MATERIALS AND METHODS

Retrospective analysis of 503 patients who underwent radical cystectomy from 2006 to 2019 for muscle-invasive urothelial bladder carcinoma, of which 152 patients with pathological node-positive disease were analyzed. Demographic details, pathological findings, treatment details, disease-free, and overall survival were documented. X tile program analysis was used to divide patients with positive lymph nodes into 3 groups: LD1: <= 7, LD2 :>7 to <15, LD3: >15, and the optimal cut-off value obtained was 15%. To evaluate the impact of lymph node ratio, patients with positive lymph nodes into 3 categories for each cut-off point estimation method, the application generates the histogram, Kaplan-Meier plot and calculates hazard ratio, confidence intervals and P-values. Univariate and multivariate cox regression analysis was done with a P-value of <.05, considered significant.

RESULTS

One hundred fifty-two patients (30.2%) had pathological nodal metastasis, with 87 of them having perinodal extension. Ninety-six underwent primary surgery, and 56 were postneoadjuvant chemotherapy. The median follow-up was 55.42 months. 68 of the 152 node-positive patients died of the disease. Median number of lymph nodes removed was 17.11. Lymph node density divided into tertiles were LD1 <7%, LD2 7-<15%, LD3 >15% showed 5-year RFS 40.5%,29.3%, 22.6% and 5 year OS was 55.5%, 42.4%,32.1% respectively. Cox regression analysis showed that age less than 55 years ,higher tumor stage, lymphovascular invasion, and higher lymph node ratio were significant in univariate and multivariate analysis. The lymph node density cut-off value of 15% was substantial among node-positive patients (P = .027), and subgroup analysis in upfront surgery with the adjuvant treatment group and postneoadjuvant chemotherapy group was also significant (P =.021).

CONCLUSION

Pathological higher T stage, Age <55 years, Lymphovascular invasion, adjuvant chemotherapy , adjuvant radiation treatment and lymph node density had prognostic significance in both cohorts of patients who underwent upfront surgery and neoadjuvant chemotherapy. Lymph node density cut-off value of <15% was prognostically significant.

Determinants of adequate lymph node dissection following neoadjuvant chemotherapy in patients with urothelial muscle-invasive bladder cancer: results from the National Cancer Database

PURPOSE

Recent literature has separately identified multiple determinants of the use of neoadjuvant chemotherapy (NAC) and adherence to pelvic lymph node dissection (PLND) guidelines in the management of non-metastatic bladder cancer. However, such NAC/PLND analyses tend not to account for the other modality, despite the fact that NAC may impact the extent of dissectible lymph nodes. We aimed to determine the predictors of adequate PLND in patients with non-metastatic urothelial muscle-invasive bladder cancer (MIBC) undergoing radical cystectomy (RC) following receipt of NAC.

METHODS

We queried the National Cancer Database to identify patients from 2006-2015 with cT2-cT4a/N0M0 urothelial MIBC who underwent RC and were pre-treated with NAC. Multivariate logistic regression analysis was used to identify independent predictors of undergoing an adequate PLND (defined as > 8 nodes).

RESULTS

A total of 1518 patients met the criteria for inclusion (74.4% underwent adequate PLND). Adequate PLND was associated with treatment at an academic research facility (OR 2.762 [95% CI 2.119-3.599], p < 0.001). The likelihood of adequate PLND was significantly decreased in patients of older age (0.607 [0.441-0.835], p = 0.002 for age 70-79 years; 0.459 [0.245-0.860], p = 0.015 for age ≥ 80 years), a Charlson-Deyo score of 1 (0.722 [0.537-0.971], p = 0.031), and those who were uninsured (0.530 [0.292-0.964], p = 0.038).

CONCLUSIONS

Established predictors of PLND may not necessarily be generalizable to all patients undergoing treatment for bladder cancer. The interplay between PLND and NAC merits further study, particularly in view of recent literature calling into question the survival benefit of PLND in patients pre-treated with NAC.

Presence of detrusor muscle in bladder tumor specimens--predictors and effect on outcome as a measure of resection quality

OBJECTIVES

To identify predictors of the absence of detrusor muscle in bladder tumor specimens and analyze its effect on clinical outcome as an indicator of resection quality.

METHODS

The bladder cancer database of a tertiary medical center was queried for patients who underwent complete transurethral resection of bladder tumor (TURBT) between 2008 and 2009. Study end points were absence of detrusor muscle in the surgical specimen and its association with disease recurrence/progression.

RESULTS

Detrusor muscle in the surgical specimen was found in 265 of the 332 study patients (79%). The likelihood of finding muscle increased with higher clinical stage (Odds Ratio [OR]-1.8), higher tumor grade (OR-3), larger tumor size (OR-3.2), multifocal disease (OR-1.7), and nonpapillary morphology (OR-2.3). History of bladder cancer, surgeon's experience, and tumor location in the bladder had no effect. In the whole study population, neither tumor recurrence nor disease progression was associated with absence of detrusor muscle. In patients with T1 tumors, absence of detrusor muscle in the specimen was associated with higher early recurrence rate but not worse long-term outcome.

CONCLUSIONS

Absence of detrusor muscle in TURBT specimens is not determined by the technical difficulty of the procedure or surgical experience. Surgeons are more prone to obtain deep muscle in large, nonpapillary-appearing tumors, likely reflecting efforts to attain accurate staging in these cases. The presence or absence of detrusor muscle may serve as a surrogate of resection quality in patients with T1 tumors, but its general applicability to the overall population of patients undergoing TURBT remains questionable.

Diagnostic value of circulating tumor cell detection in bladder and urothelial cancer: systematic review and meta-analysis

Background

The diagnostic value and prognostic significance of circulating tumor cell (CTC) detection in patients with bladder cancer is controversial. We performed a meta-analysis to consolidate current evidence regarding the use of CTC detection assays to diagnose bladder and other urothelial cancers and the association of CTC positivity with advanced, remote disease.

Methods

Studies that investigated the presence of CTCs in the peripheral blood of patients with bladder cancer and/or urothelial cancer were identified and reviewed. Sensitivities, specificities, and positive (LR+) and negative likelihood ratios (LR-) of CTC detection in individual studies were calculated and meta-analyzed by random effects model. Overall odds ratio of CTC positivity in patients with advanced disease versus those with organ-confined cancer was also calculated.

Results

Overall sensitivity of CTC detection assays was 35.1% (95%CI, 32.4-38%); specificity, LR+, and LR- was 89.4% (95%CI, 87.2-91.3%), 3.77 (95%CI, 1.95-7.30) and 0.72 (95%CI, 0.64-0.81). CTC-positive patients were significantly more likely to have advanced (stage III-IV) disease compared with CTC-negative patients (OR, 5.05; 95%CI, 2.49-10.26).

Conclusions

CTC evaluation can confirm tumor diagnosis and identify patients with advanced bladder cancer. However, due to the low overall sensitivity, CTC detection assays should not be used as initial screening tests.

Lymphadenectomy in management of invasive bladder cancer

Radical cystectomy with pelvic lymphadenectomy represents the gold standard for treatment of muscle-invasive bladder cancer. Extent of the lymph node dissection and lymph node involvement during radical cystectomy are the most powerful prognostic factors associated with poor oncological outcome. However, the optimal boundaries of the lymph node dissection during a radical cystectomy are controversial. The published literature based mostly on retrospective studies suggests that increasing the number of nodes excised may have therapeutic and diagnostic benefits without significantly increasing the surgical morbidity. These conclusions are, however, influenced by selection and surgeon biases, inconsistencies in the quality of the surgery, and node count variability. In this paper, we establish the current understanding about the utility of lymphadenectomy during a radical cystectomy for muscle-invasive bladder cancer.

The presence of circulating tumor cells does not predict extravesical disease in bladder cancer patients prior to radical cystectomy

OBJECTIVE

Due to imprecise clinical staging, the finding of extravesical and node-positive disease at the time of radical cystectomy (RC) for patients with clinically localized bladder cancer is not uncommon. Circulating tumor cells (CTCs) have been shown to be present in the peripheral blood of patients with metastatic urothelial carcinoma. The object of this study was to evaluate the ability of CTCs to predict extravesical disease in bladder cancer patients prior to RC.

MATERIALS AND METHODS

Peripheral blood samples from 43 patients with bladder cancer were evaluated using the CellSearch (Veridex, LLC, Raritan, NJ) CTC assay prior to RC. The sensitivity, specificity, and positive predictive value (PPV) of CTC status in predicting extravesical disease was calculated. Receiver operating characteristic (ROC) curves were generated to quantify the ability of CTCs to predict extravesical and node-positive disease.

RESULTS

CTCs were detected in 9 (21%) patients prior to RC. The sensitivity, specificity, and PPV of CTC status in predicting extravesical disease were 27%, 88% and 78%, respectively. The accuracy of CTC status in predicting extravesical (≥pT3 or node-positive) disease for the entire cohort was 0.576. In a model incorporating preoperative hydronephrosis, CTC status did not improve the predictive accuracy for extravesical disease (0.576 vs. 0.585, P = 0.915).

CONCLUSION

CTCs were detected in low numbers in a small percentage (21%) of patients prior to undergoing RC at our institution. CTC status was not a robust predictor of extravesical or node-positive disease in this cohort. CTC status is not likely to be a clinically useful parameter for directing therapeutic decisions in patients with ≤cT2 bladder cancer.

Assessing the minimum number of lymph nodes needed at radical cystectomy in patients with bladder cancer

OBJECTIVE

To identify the likelihood of finding one or more positive lymph nodes (LNs) according to the number of LNs removed at radical cystectomy (RC), as the number of LNs removed affects disease progression and survival after RC.

PATIENTS AND METHODS

Between 1984 and 2003, 731 assessable patients had RC and bilateral pelvic lymphadenectomy at three different institutions. ROC curve coordinates were used to determine the probability of identifying one or more positive LNs according to the total number of removed LNs.

RESULTS

Of the 731 patients, 174 (23.8%) had LNs metastases. The mean (median, range) number of LNs removed was 18.7 (17, 1-80). The ROC coordinate-based plots of the number of removed LNs and the probability of finding one or more LNs metastases indicated that removing 45 LNs yielded a 90% probability. Conversely, removing either 15 or 25 LNs indicated, respectively, 50% and 75% probability of detecting one or more LNs metastases.

CONCLUSIONS

These data indicate that removing 25 LNs might represent the lowest threshold for the extent of lymphadenectomy at RC. Our findings confirm the importance of an extended lymph node dissection.