Lymph node density vs. the American Joint Committee on Cancer TNM nodal staging system in node-positive bladder cancer in patients undergoing extended or super-extended pelvic lymphadenectomy

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.

Nomograms for predicting survival in patients with micropapillary bladder cancer: a real-world analysis based on the surveillance, epidemiology, and end results database and external validation in a tertiary center

BACKGROUND

The present study aimed to construct and validate nomograms that can be used to predict cancer-specific survival (CSS) and overall survival (OS) in patients with micropapillary bladder cancer.

METHODS

The data of 627 patients diagnosed with micropapillary bladder cancer between 2000 and 2018 were obtained from the surveillance, epidemiology, and end results database. Patients were randomly divided into the training and internal validation sets (7:3). The Cox proportional hazards regression model was applied to evaluate the association between variables and survival and then nomograms were constructed to predict the survival of an individual patient. The performance of nomograms was validated by using calibration curves, concordance index, receiver operating characteristic curves with the calculated area under the curve and decision curve analysis in the training and internal validation set. Data from 41 micropapillary bladder cancer patients at Qilu Hospital of Shandong University from 2000 to 2022 were collected for external validation.

RESULTS

Several independent risk factors were taken into the two nomograms (CSS and OS), including age, marital status, AJCC TMN stage, surgical approach, lymph node ratio, and tumor size while the OS nomogram additionally contained race. The concordance index of the training set, internal validation set, and external verification set were all over 0.7. The calibration curve indicated good consistence between the nomogram prediction and actual survival. Area under the curve and decision curve analysis results indicated great clinical usefulness of nomograms.

CONCLUSIONS

The nomograms predicting the survival outcome of patients with micropapillary bladder cancer would provide a valuable tool to help clinicians to evaluate the risk of patients and make individual treatment strategies.

Log Odds of Positive Lymph Nodes (LODDS) as an Independent Predictor of Overall Survival Following Radical Cystectomy in Urothelial Bladder Cancer: Time to Rethink Conventional Node Staging

BACKGROUND

Radical cystectomy (RC) with lymph node dissection is the mainstay of treatment for patients with muscle-invasive bladder cancer (MIBC) and high risk non-MIBC. The American Joint Committee on Cancer's (AJCC) node staging and lymph node ratio (LNR) systems are used in estimating prognosis; however, they do not directly factor in negative dissected nodes. In this study, we evaluated the log odds of positive lymph nodes (LODDS), a novel measure of nodal involvement, as a predictor of survival.

PATIENTS AND METHODS

Eighty-three patients who underwent RC were retrospectively included and their demographic and clinical data were collected. Kaplan-Meier curve and Cox regression were used for survival analyses.

RESULTS

Median number of dissected lymph nodes was 13 (range 3-45). ROC curve analysis indicated -0.92 as the optimal LODDS cutoff. LODDS > -0.92 was associated with higher T stage, lymphovascular invasion, and significantly worse overall survival (OS) (mean OS 18.6 vs. 45.1 months, P-value < .001). Furthermore, we evaluated AJCC node staging, LNR, and LODDS in three separate multivariable Cox regression models. Among 3 different measures of nodal disease burden, only LODDS was an independent predictor of OS (HR 2.71, 95% CI 1.28-5.73, P = .009).

CONCLUSIONS

Our results show that LODDS is an independent predictor of OS and outperforms AJCC node staging and LNR in forecasting prognosis among patients with urothelial bladder cancer who undergo RC.

Extent of lymph node dissection and impact on survival in radical cystectomy for advanced bladder cancer

PURPOSE OF REVIEW

In patients with muscle invasive bladder cancer (MIBC) or unresectable non-MIBC, radical cystectomy is routinely combined with bilateral pelvic lymph node dissection (LND) owing to the oncological benefits found in recurrence-free survival (RFS), overall survival (OS) and cancer-specific survival (CSS) compared with radical cystectomy alone. However, the optimal anatomic extent of LND is still unclear.

RECENT FINDINGS

Retrospective studies were consistent in reporting oncological benefits of extended LND over nonextended LND. A recent RCT (the LEA trial) failed to demonstrate any benefit in terms of RFS, CSS and OS of super-extended LND over standard LND. Several confounding factors hindered the interpretation of the results, leaving the question of the right extent for LND still open. Results of a similar study, the SWOG S1011 are, therefore, highly anticipated. This study differed from the LEA study in several aspects but might also turn out to be a negative study.

SUMMARY

There are still no firm data on the oncological benefit brought by more extended LND in patients with MIBC. Survival benefits seem limited, at least in the general population. Other factors could influence the impact of LND on survival, including the administration of adjuvant and neoadjuvant chemotherapies.

Can American Joint Committee on Cancer prognostic groups be individualized in patients undergoing surgery for Stage IV invasive upper tract Urothelial Carcinoma?

Purpose: We explored whether the modified American Joint Committee on Cancer tumor-node-metastasis prognostic stage group IV can be individualized in a large population-based cohort of surgically treated invasive upper tract urothelial carcinoma (UTUC) patients.

Methods: Invasive UTUC patients from the Surveillance, Epidemiology and End Results database (2004-2015) were screened for inclusion. A total of 10,482 eligible cases were identified. Cancer-specific survival (CSS) after surgery was analyzed using Kaplan-Meier plots.

Results: According to the most recent pathological prognostic group classification, the 5-year mortality rates of T4NxM0 (n=493), TxN1M0 (n=597), TxN2M0 (n=424) and pTxNxM1 (n=677) patients were 41.1% (95% CI 35.2% to 47.0%), 38.6% (95% CI 33.1% to 44.1%), 40.4% (95% CI 33.0% to 47.8%) and 14.2% (95% CI 9.9% to 18.5%), respectively (T4N0M0 vs. TxNxM1, P<0.001; TxN1M0 vs. TxNxM1, P<0.001; TxN2M0 vs. TxNxM1, P<0.001). Stage IV tumors were subdivided on the basis of the mortality data (Modification 1): stage IVa tumors were considered nonmetastatic (T4NxM0, TxN1-2M0; 5-year CSS 39.9%), and stage IVb tumors were considered metastatic (pTxNxM1; 5-year CSS 14.2%). Stage IV tumors were also subdivided according to the grade classification (Modification 2): stage IVa tumors were considered low grade (T4NxM0, TxN1-2M0, TxNxM1; G1-2; n=141), and stage IVb tumors were considered metastatic (T4NxM0, TxN1-2M0, TxNxM1; G3-4; n=2050). The 5-year CSS rates for stage IVa and IVb patients were 76.3% (95% CI 68.7% to 83.9%) and 31.4% (95% CI 28.5% to 34.3%), respectively (P<0.001).

Conclusions: Stage IV patients were stratified into two prognostically different risk groups depending on metastasis or grade. The subclassification of stage IV can increase the level of prognostic detail and individualize the prediction of survival in invasive UTUC patients.

Development of a prognostic signature for bladder cancer based on immune-related genes

Background

Although the prognosis of patients with bladder cancer (BC) has improved significantly with the use of multimodal therapy, reliable prognostic biomarkers are still urgently needed due to the heterogeneity of tumors. Our aim was to develop an individualized immune-related gene pair (IRGP) signature that could precisely predict prognosis in BC patients.

Methods

Gene expression profiles and corresponding clinical information were collected from eight microarray data sets and one RNA-Seq data set.

Results

Among 1,811 immune genes, a 30-IRGP signature consisting of 52 unique genes was generated in the training cohort, which significantly stratified patients into low- and high-risk groups in terms of overall survival. In the testing and validation cohorts, the IRGP signature was also associated with patient prognosis in the univariate and multivariate Cox regression analyses. Several biological processes, including the immune response, chemotaxis, and the inflammatory response, were enriched among genes in the IRGP signature. When the signature was integrated with the TNM stage, an IRGP nomogram was developed and showed improved prognostic accuracy relative to the IRGP signature alone.

Conclusions

In short, we identified a robust IRGP signature for estimating overall survival in BC patients that could also be used as a promising biomarker for identifying high-risk patients for individualized therapy.

Prognostic Value of Lymph Node Density in Patients With T3 and T4 Pyriform Sinus Carcinoma

Background/Aim:

Lymph node density is a parameter used to more accurately predict tumor recurrence and patient survival. However, its association with surgical outcome in pyriform sinus carcinoma remains unclear. The purpose of this study was to assess the prognostic value of lymph node density in advanced pyriform sinus carcinoma.

Patients and Methods:

A total of 87 patients with pyriform sinus carcinoma treated between 2008 and 2015 were enrolled. Then, 5-year overall survival, 5-year disease-specific survival, 5-year disease-free survival, and 5-year regional recurrence-free survival were utilized to assess the prognostic significance of lymph node density.

Results:

With a median follow-up period of 31.8 months, 5-year overall survival, disease-specific survival, disease-free survival, and regional recurrence-free survival were 37.9%, 46.0%, 41.4%, and 54.0%, respectively. Univariate analysis revealed that lymph node density ≥ 0.093 was a significant predictor of poor 5-year overall survival (P = .005), disease-specific survival (P = .008), disease-free survival (P = .0013), and regional recurrence-free survival (P = .003). Furthermore, multivariate analysis demonstrated that lymph node density was negatively associated with adverse 5-year overall survival (hazard ratio = 1.62, 95% CI: 1.15-2.29, P = .006), disease-specific survival (hazard ratio = 1.86, 95% CI: 1.24-2.80, P = .003), disease-free survival (hazard ratio = 0.45, 95% CI: 0.24-0.85, P = .014), and regional recurrence-free survival (hazard ratio = 2.97, 95% CI: 1.43-6.17, P = .004).

Conclusion:

Taken together, these results reveal that lymph node density is a powerful prognostic factor for patients with T3 and T4 pyriform sinus carcinoma, and the median lymph node density cutoff values ≥ 0.093 are associated with a greater risk of recurrence and poorer survival.

The Cancer of the Bladder Risk Assessment (COBRA) score for estimating cancer-specific survival after radical cystectomy: external validation in a large bi-institutional cohort

OBJECTIVE

To perform an external validation of the Cancer of the Bladder Risk Assessment (COBRA) score for estimating cancer-specific survival (CSS) after radical cystectomy (RC) in a large bi-institutional cohort of patients.

PATIENTS AND METHODS

Patients treated with RC and lymph node dissection (LND) between May 1996 and July 2017 were retrieved from the RC databases of Leuven and Turin. Collected variables were age at RC, tumour stage, lymph node (LN) density, neoadjuvant chemotherapy, the extent of LND, and nodal stage. The primary outcome was CSS visualised using Kaplan-Meier plots. Cox proportional hazard models were used to assess the impact of variables on CSS. We performed a pairwise comparison between the COBRA score levels using a log-rank test corrected by Bonferroni, and developed a simplified COBRA score with three risk categories. To compare models, we assessed concordance indices (C-indices), receiver operating characteristic curves with area under the curve (AUC), calibration plots, and decision curve analysis (DCA). Finally, we compared both COBRA and simplified COBRA models with the established American Joint Committee on Cancer (AJCC) model.

RESULTS

A total of 812 patients were included. All COBRA score variables had a significant impact on CSS in a Cox proportional hazard model. However, pairwise comparison of the COBRA subscores could not differentiate significantly between all COBRA score levels. Based on these findings, we developed a simplified COBRA score by introducing three categories within the following COBRA score ranges: low- (0-1) vs intermediate- (2-4) vs high-risk (5-7). A pairwise comparison could discriminate significantly between all COBRA risk categories. When finally comparing COBRA and simplified COBRA models with the AJCC model, AJCC performed better than both. C-indices, AUCs, calibration plots and DCA for AJCC were all better compared with the original and simplified COBRA models.

CONCLUSION

We performed an external validation of the COBRA score in a large bi-institutional cohort. We observed that several risk groups had overlapping CSS, demonstrating suboptimal performance of the COBRA score. Therefore, we constructed a simplified model with three COBRA score risk categories. This model resulted in demarcated risk groups with non-overlapping CSS and good predictive accuracy. However, both COBRA score models were outperformed by the AJCC staging system. Therefore, we conclude that the AJCC staging system should remain the current standard for stratifying patients after RC for CSS.

Impact of lymph node dissection in radical cystectomy for bladder cancer: How many vs how far?

PURPOSE

To determine whether the extent or number of lymph nodes (LNs) is important in muscle-invasive bladder cancer and high-risk non-muscle-invasive bladder cancer patients' oncologic outcomes.

METHODS

A total of 448 patients who underwent radical cystectomy with lymphadenectomy of standard, extended, and super-extended template were included. Exclusion criteria were neoadjuvant chemotherapy and limited lymphadenectomy. Disease-free survival (DFS) including local recurrence and distant metastasis, cancer-specific survival (CSS), and overall survival (OS) were estimated using the Kaplan-Meier method. Cox hazard regression was applied to analyze risk factors.

RESULTS

Standard (n = 124), extended (n = 216), and super-extended group (n = 108) did not show significant differences in the estimated 5-year DFS, CSS and OS rates. On multivariate analysis, the number of removed LNs was a significant factor for distant metastasis-free (hazard ratio [HR] 0.981, p = 0.0222), CSS (HR 0.980, p = 0.0021) and OS (HR 0.984, p = 0.0032). However, the template was not significant in distant metastasis-free survival, CSS and OS. On Kaplan-Meier curve, the number of removed LN showed significant differences in DFS, CSS, and OS. In the subgroup of positive LNs, number of removed LNs was associated with favorable DFS (HR = 0.969, p = 0.0115), CSS (HR = 0.967, p = 0.0068) and OS (HR = 0.971, p = 0.0028).

CONCLUSION

The number of removed LNs was a more important factor for CSS and OS than the extent of lymphadenectomy. Meticulous and extended LN dissection can be helpful in controlling recurrence, and its survival benefit might be maximized in cases with positive LN. Meanwhile, the survival benefit of super-extended lymphadenectomy was limited for this patient population.

Lymphadenectomy for Muscle-Invasive Bladder Cancer and Upper Tract Urothelial Cell Carcinoma

There are currently no reported randomized trials that characterize the staging or therapeutic benefit of performing a lymph node dissection in either bladder cancer or upper tract urothelial carcinoma. Several unanswered questions remain in this domain focused on the indications and patient selection for pelvic lymph node dissection, extent of dissection, its impact on outcome, and potential risks. However, the results of observational studies suggest that the burden of metastasis is high in both diseases when muscle invasive and performing a lymphadenectomy can provide prognostic information and yield therapeutic benefit.

A practical guide to bladder cancer pathology

Pathological assessment of bladder cancer is becoming an increasingly complex task owing to the growing availability of molecular data for different histological subtypes and the appreciation of their importance in determining outcomes of neoadjuvant chemotherapy. Urologists are aware of the need to closely collaborate with pathologists, and comprehensive sharing of information is crucial to achieve optimal patient management. Numerous steps towards this goal have been made during the past years. Important advances in the assessment and reporting of grading and staging, especially substaging of pT1 urothelial carcinomas, have been made. As part of the International Collaboration on Cancer Reporting (ICCR), an international expert group has suggested worldwide reporting standards for urothelial lesions. Nevertheless, several issues remain unresolved, for example, regarding the reporting of heterogeneous lesions and substaging as well as the gross handling and the reporting for lymphadenectomy specimens. During the past few years, major insights have been gained into the molecular changes that occur during bladder cancer development, but a consensus on how to integrate these data into daily practice has not been achieved.