External Validation of Bladder Cancer Predictive Nomograms for Recurrence, Cancer-Free Survival and Overall Survival following Radical Cystectomy

Association of Tumor-informed Circulating Tumor DNA Detectability Before and After Radical Cystectomy with Disease-free Survival in Patients with Bladder Cancer

BACKGROUND AND OBJECTIVE

Despite curative-intent radical cystectomy (RC), patients with muscle-invasive bladder cancer (MIBC) are at high risk of recurrence. Biomarkers are urgently needed to refine prognostication and selection of appropriate perioperative systemic therapies. Our aim was to evaluate the prognostic and predictive value of tumor-informed circulating tumor DNA (ctDNA) results in a multicenter cohort of patients with bladder cancer who underwent RC.

METHODS

We performed a retrospective analysis of real-world data for a commercial ctDNA test (Signatera; Natera, Austin, TX, USA) performed in 167 patients (852 plasma samples) before RC and during molecular residual disease (MRD; adjuvant decision) and surveillance windows. We assessed the correlation between recurrence and ctDNA status before and after RC using Cox regression analysis.

RESULTS AND LIMITATIONS

During study-defined postoperative MRD and surveillance windows, detectable ctDNA was associated with shorter disease-free survival (DFS) when compared to undetectable ctDNA (MRD: hazard ratio 6.93; p < 0.001; surveillance: hazard ratio 23.02; p < 0.001). Of note, patients with undetectable ctDNA did not appear to benefit from adjuvant therapy (p = 0.34). Detectable ctDNA in the pre-RC (p = 0.045), MRD (p = 0.002), and surveillance (p < 0.001) windows was the only risk factor independently associated with shorter DFS. Limitations include the retrospective and nonrandomized nature of the study.

CONCLUSIONS

ctDNA testing in patients with bladder cancer undergoing RC was prognostic and potentially predictive. Identification of patients at high risk of recurrence may aid in patient counseling and decision-making.

PATIENT SUMMARY

We found that outcomes for patients with muscle-invasive bladder cancer are strongly linked to detection of tumor DNA in blood samples. The results show the value of tumor-informed testing for tumor DNA in blood for decisions on the best treatment for each individual patient.

Survival nomogram for high-grade bladder cancer patients after surgery based on the SEER database and external validation cohort

Background

The aim of this study was to develop a comprehensive and effective nomogram for predicting overall survival (OS) rates in postoperative patients with high-grade bladder urothelial carcinoma.

Methods

Patients diagnosed with high-grade urothelial carcinoma of the bladder after radical cystectomy (RC) between 2004 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database were enrolled. We randomly split (7:3) these patients into the primary cohort and the internal validation cohort. Two hundred eighteen patients from the First Affiliated Hospital of Nanchang University were collected as the external validation cohort. Univariate and multivariate Cox regression analyses were carried out to seek prognostic factors of postoperative patients with high-grade bladder cancer (HGBC). According to these significant prognostic factors, a simple-to-use nomogram was established for predicting OS. Their performances were evaluated using the concordance index (C-index), the receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

Results

The study included 4,541 patients. Multivariate Cox regression analysis demonstrated that T stage, positive lymph nodes (PLNs), age, chemotherapy, regional lymph nodes examined (RLNE), and tumor size were correlated with OS. The C-index of the nomogram in the training cohort, internal validation cohort, and external validation cohort were 0.700, 0.717, and 0.681, respectively. In the training, internal validation, and external validation cohorts, the ROC curves showed that the 1-, 3-, and 5-year areas under the curve (AUCs) were higher than 0.700, indicating that the nomogram had good reliability and accuracy. The results of calibration and DCA showed good concordance and clinical applicability.

Conclusion

A nomogram was developed for the first time to predict personalized 1-, 3-, and 5-year OS in HGBC patients after RC. The internal and external validation confirmed the excellent discrimination and calibration ability of the nomogram. The nomogram can help clinicians design personalized treatment strategies and assist with clinical decisions.

Predictive Value of the Log Odds of Negative Lymph Nodes/T Stage as a Novel Prognostic Factor in Bladder Cancer Patients After Radical Cystectomy

Background

The effect of lymph node resection on the prognosis of bladder cancer (BLCA) patients receiving radical cystectomy should not be ignored. Our aim was to explore the prognostic value of the log odds of negative lymph nodes/T stage (LONT) and construct a more effective nomogram based on LONT to predict cancer-specific survival (CSS) in postoperative BLCA patients.

Methods

Patients diagnosed with BLCA after radical cystectomy between 2004 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database were enrolled. We randomly split (7:3) these patients into the primary cohort and internal validation cohort. 86 patients from the First Affiliated Hospital of Nanchang University were collected as the external validation set. Univariate and multivariate cox regression analyses were carried out to seek prognostic factors of postoperative BLCA patients. According to these significantly prognostic factors, a simple-to-use nomogram was established for predicting CSS. Their performances were evaluated by using calibration curves, the concordance index (C-index), the receiver operating characteristic (ROC) curves, and decision curve analysis (DCA). In addition, different risk groups were tested by Kaplan-Meier curves and log-rank tests.

Result

Whether in cancer-specific survival (CSS) or overall survival (OS), LONT was an independent and significant prognostic factor. Through further screening, the ultimate nomogram of CSS was composed of nine independent prognostic factors including LONT, age, race, tumor size, histologic type, T stage, N stage, summary stage and chemotherapy. The C-index of nomogram in the primary cohort, internal and external validation cohort were 0.734, 0.720 and 0.728, respectively. The AUC of predicting CSS at 3 and 5 years were 0.783 and 0.774 in the primary cohort and 0.781 and 0.781 in the validation cohort. The results of calibration and DCA showed good concordance and clinical applicability. Significant differences (P < 0.05) were displayed in CSS among different risk groups.

Conclusion

LONT was regarded as a novel and reliable prognostic factor. Compared with the AJCC staging system, the established nomogram based on LONT can more effectively predict the prognosis of BLCA patients after radical cystectomy.

Progress in the development of tissue-based biomarkers for urothelial cancer

INTRODUCTION

As the understanding of molecular mechanisms of bladder cancer advances, molecularly-guided precision medicine becomes increasingly relevant. Biomarkers play a critical role in this setting, predicting treatment response and identifying candidates for targeted therapies.

AREAS COVERED

Current literature on biomarkers in their role in disease prognosis, and response to neoadjuvant and adjuvant therapies. In non-muscle invasive bladder cancer, particular focus is on markers of disease progression, and response to intravesical therapy. In muscle invasive and advanced bladder cancer, particular emphasis is on markers associated with neoadjuvant chemotherapy, as well as systemic immunotherapy. We discuss current shortcomings and pitfalls in contemporary markers, and future avenues of prospective research.

EXPERT OPINION

The focus on biomarkers has moved from immunohistochemical analysis and tumor-related phenotypic changes to examining genetic alterations. Single marker analysis has been shown to be insufficient in predicting both disease course and response to therapy, and studies have shifted towards examining marker combinations and genetic classifiers. Ultimately, significant progress in implementing biomarkers into clinical guidelines remains elusive, largely due to lack of prospective studies in well-defined patient cohorts and with clinically-meaningful endpoints. Until then, despite their promising value, tissue markers should be limited to experimental settings and clinical trials.

Trends of incidence and prognosis of primary adenocarcinoma of the bladder

BACKGROUND

Primary adenocarcinoma of the bladder (ACB) is a rare malignant tumor of the bladder with limited understanding of its incidence and prognosis.

METHODS

Patients diagnosed with ACB between 2004 and 2015 were obtained from the SEER database. The incidence changes of ACB patients between 1975 and 2016 were detected by Joinpoint software. Nomograms were constructed based on the results of multivariate Cox regression analysis to predict overall survival (OS) and cancer-specific survival (CSS) in patients with ACB, and the constructed nomograms were validated.

RESULTS

The incidence of ACB was trending down from 1991 to 2016. A total of 1039 patients were included in the study and randomly assigned to the training cohort (727) and validation cohort (312). In the training cohort, multivariate Cox regression showed that age, marital status, primary site, histology type, grade, AJCC stage, T stage, SEER stage, surgery, radiotherapy, and chemotherapy were independent prognostic factors for OS, whereas these were age, marital status, primary site, histology type, grade, AJCC stage, T/N stage, SEER stage, surgery, and radiotherapy for CSS. Based on the above Cox regression results, we constructed prognostic nomograms for OS and CSS in ACB patients. The C-index of the nomogram OS was 0.773 and the C-index of CSS was 0.785, which was significantly better than the C-index of the TNM staging prediction model. The area under the curve (AUC) and net benefit of the prediction model were higher than those of the TNM staging system. In addition, the calibration curves were very close to the ideal curve, suggesting appreciable reliability of the nomograms.

CONCLUSION

The incidence of ACB patients showed a decreasing trend in the past 25 years. We constructed a clinically useful prognostic nomogram for calculating OS and CSS of ACB patients, which can provide a personalized risk assessment for ACB patient survival.

Development and validation of a prognostic nomogram for predicting cancer-specific survival after radical cystectomy in patients with bladder cancer:A population-based study

Purpose

To establish a prognostic model to estimate the cancer‐specific survival (CSS) for urothelial carcinoma of bladder (UCB) patients after radical cystectomy (RC).

Methods

A total of 8650 candidates (2004–2011) obtained from the Surveillance, Epidemiology, and End Results (SEER) database were randomly split into development cohort (n = 4323) and validation cohort (n = 4327). We performed Cox regression analysis to identify prognostic factors and Kaplan‐Meier analysis to assess survival outcome. A nomogram predicting CSS was constructed. Its performance was validated by calibration curves, the receiver operating characteristic (ROC) curves, concordance index (C‐index), decision curve analysis (DCA), the net reclassification improvement (NRI), and the integrated discrimination improvement (IDI).

Results

The nomogram incorporated marital status, T stage, N stage, tumor size, and chemotherapy. In validation cohort, C‐index of the nomogram was 0.707. AUC of the nomogram and AJCC stage were 0.767 versus 0.674. Calibration plots for 3‐ and 5‐year CSS displayed good concordance. DCA curves of the nomogram exhibited larger benefits than the AJCC stage. The NRI and IDI indicated the nomogram outperformed AJCC stage.

Conclusions

We have established a prognostic nomogram with improved discriminative ability and clinical benefits for UCB patients after RC. The nomogram alongside an easy access web tool may assist clinicians in optimizing the postoperative management.

Clinical markers of morbidity, mortality and survival in bladder cancer patients treated with radical cystectomy. A systematic review

Context: Radical cystectomy and pelvic lymph node dissection (RC and PLND) are an essential part of the treatment paradigm in high risk bladder cancer. However, these patients have high rates of morbidity and mortality related both to the treatment and to the disease.Objective: To provide overview of current literature about clinical markers that can be used to predict and improve BC-patient outcomes at the time of RC and PLND and to study if they are properly validated.Evidence acquisition: A systematic literature search was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria between January 1990 and October 2018 to identify English written original and review articles relevant to this topic. Prospective and retrospective studies were included.Evidence synthesis: There are several risk factors identified from non-randomised trials that can be improved before surgery to reduce perioperative mortality and morbidity. These include poor nutritional status, anaemia, renal function and smoking. Preoperative nomograms have also been developed to help decision-making and to inform patients about the risks of surgery. They can be used to estimate risk of postoperative mortality after RC and PLND with accuracy varying from 70 to 86%. These nomograms are largely based on retrospective data. Likewise, nomograms developed to calculate estimates about patient's overall and cancer specific survival have the same limitations.Conclusion: Clinical markers to predict morbidity, mortality and survival in patients with bladder cancer treated with RC and PLND may help to improve patient outcomes and treatment decision-making, but available data come from small retrospective trials and have not been properly validated. Prospective, multi-centre studies are needed to implement and disseminate predictive clinical markers and nomograms such that they can be utilised in treatment decision-making in daily practice.

Mortality prediction model for patients with bladder urothelial tumor after radical cystectomy

OBJECTIVE

Based on preoperative clinical and postoperative pathological variables, we aim to build a prediction model of cancer specific mortality (CSM) at 1, 3, and 5 years for patients with bladder transitional cell carcinoma treated with RC.

MATERIAL AND METHODS

Retrospective analysis of 517 patients with diagnosis of cell carcinoma treated by RC (1986-2009). Demographic, clinical, surgical and pathological variables were collected, as well as complications and evolution after RC. Comparative analysis included Chi square test and ANOVA technique. Survival analysis was performed using Kaplan-Meier method and log-rank test. Univariate and multivariate analyses were performed using logistic regression to identify the independent predictors of CSM. The individual probability of CSM was calculated at 1, 3 and 5 years according to the general equation (logistic function). Calibration was obtained by the Hosmer-Lemeshow method and discrimination with the elaboration of a ROC curve (area under the curve).

RESULTS

BC was the cause of death in 225 patients (45%). One, three and five-year CSM were 17%, 39.2% and 46.3%, respectively. The pT and pN stages were identified as independent prognostic variables of CSM at 1, 3 and 5 years. Three prediction models were built. The predictive capacity was 70.8% (CI 95% 65-77%, p=.000) for the 1st year, 73.9% (CI95% 69.2-78.6%, p=.000) for the third and 73.2% (CI% 68.5-77.9%, p=.000) for the 5th.

CONCLUSIONS

The prediction model allows the estimation of CSM risk at 1, 3 and 5 years, with a reliability of 70.8, 73.9 and 73.2%, respectively.

Application of nomograms in the prediction of overall survival and cancer-specific survival in patients with T1 high-grade bladder cancer

To predict survival outcomes for individual patients with clinical T1 high-grade (T1HG) bladder cancer (BC), data from the Surveillance Epidemiology and End Results (SEER) database were analyzed in the present study. The data of 6,980 cases of T1HG BC between 2004 and 2014 were obtained from the SEER database. Uni- and multivariate Cox analyses were performed to identify significant prognostic factors. Subsequently, prognostic nomograms for predicting 3- and 5-year overall survival (OS) and cancer-specific survival (CSS) rates were constructed based on the SEER database. Clinical information from the SEER database was divided into internal and external groups and used to validate the nomograms. In addition, calibration plot diagrams and concordance indices (C-indices) were used to verify the predictive performance of the nomogram. A total of 6,980 patients were randomly allocated to the training cohort (n=4,886) or the validation cohort (n=2094). Univariate and multivariate Cox analyses indicated that age, ethnicity, tumor size, marital status, radiation and surgical status were independent prognostic factors. These characteristics were used to establish nomograms. The C-indices for OS and CSS rate predictions for the training cohort were 0.707 (95% CI, 0.693–0.721) and 0.700 (95% CI, 0.679–0.721), respectively. Internal and external calibration plot diagrams exhibited an excellent consistency between actual survival rates and nomogram predictions, particularly for 3- and 5-year OS and CSS. The significant prognostic factors in patients with T1HG BC were age, ethnicity, marital status, tumor size, status of surgery and use of radiation. In the present study, a nomogram was developed that may serve as an effective and convenient evaluation tool to help surgeons perform individualized survival evaluations and mortality risk determination for patients with T1HG BC.

Nomograms Predict Survival Advantages of Gleason Score 3+4 Over 4+3 for Prostate Cancer: A SEER-Based Study

Background: Different proportions of Gleason pattern 3 and Gleason pattern 4 lead to various prognosis of prostate cancer with Gleason score 7. The objective of this study was to compare the survival outcomes of Gleason score 3+4 and 4+3 based on data from the Surveillance, Epidemiology, and End Results cancer registry database, and to investigate independent prognosis-associated factors and develop nomograms for predicting survival in Gleason score 7 prostate cancer patients.

Methods: A retrospective study was conducted on 69,116 cases diagnosed as prostate adenocarcinoma with Gleason score 7 between 2004 and 2009. Prognosis-associated factors were evaluated using univariate and multivariate Cox regression analysis, and a 1:1 ratio paired cohort by propensity score matching with the statistical software IBM SPSS, to evaluate prognostic differences between Gleason score 3+4 and 4+3. The primary cohort was randomly divided into training set (n = 48,384) and validation set (n = 20,732). Based on the independent factors of prognosis, nomograms for prognosis were established by the training group and validated by the validation group using R version 3.5.0.

Results: After propensity score matching, Cox regression analysis showed that Gleason 4+3 had an increased mortality risk both for overall survival (HR: 1.235, 95% CI: 1.179–1.294, P < 0.001) and cancer-specific survival (HR: 1.606, 95% CI: 1.468–1.762, P < 0.001). Nomograms for overall survival and cancer-specific survival were established with C-index 0.786 and 0.842, respectively. The calibration plot indicated an optimal agreement between the actual observation and nomogram prediction for overall survival and cancer-specific survival probability at 5 or 10 year.

Conclusions: Prostate cancer with Gleason score 4+3 had worse overall survival and cancer-specific survival than Gleason score 3+4. Nomograms were formulated to predict 5-year and 10-year OS and CSS in patients with prostate cancer of Gleason score 7.

The expression profile of p14, p53 and p21 in tumour cells is associated with disease-specific survival and the outcome of postoperative chemotherapy treatment in muscle-invasive bladder cancer

PURPOSE

We investigated the effects of alterations in the biological markers p14, p53, p21, and p16 in relation to tumour cell proliferation, T-category, N- category, lymphovascular invasion, and the ability to predict prognosis in patients with muscle-invasive bladder cancer (MIBC) treated with cystectomy and, if applicable, chemotherapy.

MATERIALS AND METHODS

We prospectively studied patients with urinary bladder cancer pathological stage pT1 to pT4 treated with cystectomy, pelvic lymph node dissection and postoperative chemotherapy. Tissue microarrays from paraffin-embedded cystectomy tumour samples were examined for expression of immunostaining of p14, p53, p21, p16 and Ki-67 in relation to other clinical and pathological factors as well as cancer-specific survival.

RESULTS

The median age of the 110 patients was 70 years (range 51-87 years), and 85 (77%) were male. Pathological staging was pT1 to pT2 (organ-confined) in 28 (25%) patients and pT3 to pT4 (non-organ-confined) in 82 (75%) patients. Lymph node metastases were found in 47 patients (43%). P14 expression was more common in tumours with higher T-stages (P = 0.05). The expression of p14 in p53 negative tumours was associated with a significantly shorter survival time (P=0.003). Independently of p53 expression, p14 expression was associated with an impaired response to chemotherapy (P=0.001). The expression of p21 in p53 negative tumours was associated with significantly decrease levels of tumour cell proliferation detected as Ki-67 expression (P=0.03).

CONCLUSIONS

The simultaneous expression of the senescence markers involved in the p53-pathway shows a more relevant correlation to the pathological outcome of MIBC than each protein separately. P14 expression in tumours with non-altered (p53-) tumours is associated with poor prognosis. P14 expression is associated with impaired response to chemotherapy. P21 expression is related to decreased tumour cell proliferation.

Nomograms to Predict Individual Prognosis of Patients with Primary Small Cell Carcinoma of the Bladder

Objectives: To develop reliable nomograms to estimate individualized overall survival (OS) and cancer specific survival (CSS) for patients with primary small cell carcinoma of the bladder (SCCB) and compare the predictive value with the AJCC stages.

Patients and Methods: 582 eligible SCCB patients identified in the Surveillance, Epidemiology, and End Results (SEER) dataset were randomly divided into training (n=482) and validation (n=100) cohorts. Akaike information criterion was used to select the clinically important variables in multivariate Cox models when establishing nomograms. The performance of nomograms was bootstrapped validated internally and externally using the concordance index (C-index) with 95% confidence interval (95% CI) and calibration curves and was compared with that of the AJCC stages using C-index, Kaplan-Meier curves and decision curve analysis (DCA).

Results: Two nomograms shared common indicators including age, tumor size, T stage, lymph node ratio, metastases, chemotherapy, radiation and radical cystectomy, while marriage and gender were only incorporated in the OS nomogram. The C-indices of nomograms for OS and CSS were 0.736 (95%CI 0.711-0.761) and 0.731(95%CI 0.704-0.758), respectively, indicating considerable predictive accuracy. Calibration curves showed consistency between the nomograms and the actual observation. The results remained reproducible when nomograms were applied to the validation cohort. Additionally, comparisons between C-indices, Kaplan-Meier curves and DCA proved that the nomograms obtained obvious superiority over the AJCC stages with wide practical threshold probabilities.

Conclusions: We proposed the first two nomograms for individualized prediction of OS and CSS in SCCB patients with satisfactory predictive accuracy, good robustness and wide applicability.

Cancer and All-cause Mortality in Bladder Cancer Patients Undergoing Radical Cystectomy: Development and Validation of a Nomogram for Treatment Decision-making

OBJECTIVE

To develop and validate a nomogram assessing cancer and all-cause mortality following radical cystectomy. Given concerns regarding the morbidity associated with surgery, there is a need for incorporation of cancer-specific and competing risks into patient counseling and recommendations.

MATERIALS AND METHODS

A total of 5325 and 1257 diagnosed with clinical stage T2-T4a muscle-invasive bladder cancer from January 1, 2006 to December 31, 2011 from Surveillance, Epidemiology, and End Results-Medicare and Texas Cancer Registry-Medicare linked data, respectively. Cox proportional hazards models were used and a nomogram was developed to predict 3- and 5-year overall and cancer-specific survival with external validation.

RESULTS

Patients who underwent radical cystectomy were mostly younger, male, married, non-Hispanic white and had fewer comorbidities than those who did not undergo radical cystectomy (P < .001). Married patients, in comparison with their unmarried counterparts, had both improved overall (hazard ratio 0.76; 95% confidence interval 0.70-0.83, P < .001) and cancer-specific (hazard ratio 0.76; 95% confidence interval 0.68-0.85, P < .001) survival. A nomogram developed using Surveillance, Epidemiology, and End Results-Medicare data, predicted 3- and 5-year overall and cancer-specific survival rates with concordance indices of 0.65 and 0.66 in the validated Texas Cancer Registry-Medicare cohort, respectively.

CONCLUSION

Older, unmarried patients with increased comorbidities are less likely to undergo radical cystectomy. We developed and validated a generalizable instrument that has been converted into an online tool (Radical Cystectomy Survival Calculator), to provide a benefit-risk assessment for patients considering radical cystectomy.