Ajay Gopalakrishna

Multi-institutional external validation of urinary TWIST1 and NID2 methylation as a diagnostic test for bladder cancer

OBJECTIVES We previously reported a clinical trial in which we were unable to replicate the excellent diagnostic metrics produced in the developmental study of the TWIST1 and NID2 gene methylation assay. In this expanded trial with subjects enrolled from another institution, we reexamine the diagnostic capabilities of the test to externally validate our previous study. MATERIALS AND METHODS TWIST1 and NID2 gene methylation was assessed in DNA isolated from the urine of subjects at risk of bladder cancer undergoing cystoscopy for hematuria or bladder cancer surveillance. The diagnostic gold standard was cystoscopy. Two thresholds of TWIST1 and NID2 gene methylation were used for determining test result positivity, those published by Renard et al. and Abern et al. The sensitivity, specificity, positive and negative predictive values, diagnostic likelihood ratios, and receiver operating characteristic curves were calculated for each gene, as well as their combination. In all, 3 methods were used to combine TWIST1 and NID2 into a single composite test: (1) believe-the-positive decision rule-if either gene is methylated the test result is positive, which maximizes test sensitivity; (2) believe-the-negative decision rule-if either gene is not methylated the test result is negative, which maximizes test specificity; and (3) a likelihood-based logistic regression model approach that balances sensitivity and specificity. Clinical utility was determined using a decision curve analysis. RESULTS A total of 209 subjects were evaluated: 40% for hematuria and 60% for bladder cancer surveillance. Approximately 75% were male, most of the prior cancers being low-grade Ta. Using cystoscopy as the gold standard, areas under the curve were 0.67 for TWIST1, 0.64 for NID2, and 0.66 for combined TWIST1 and NID2. Decision rule results revealed optimization of sensitivity at 67% using Renard thresholds and specificity using the Abern thresholds at 69%. We found improved sensitivity (78%) in current smokers. Decision curve analyses revealed that the methylation assay provided only a modest benefit even at high probabilities of missed cancer. CONCLUSION A urine DNA test measuring TWIST1 and NID2 methylation was externally examined with a larger cohort and its results continue to be poor. These 2 biomarkers are unlikely to replace cystoscopy, but they may be worthy of study in active smokers.

A systematic review of regional hyperthermia therapy in bladder cancer

Abstract Context: Bladder cancer therapy remains suboptimal as morbidity and mortality remain high amongst those with non-muscle-invasive and muscle-invasive disease. Regional hyperthermia therapy (RHT) is a promising adjunctive therapy being tested in multiple clinical contexts. Objective: The aim of this study was to systematically review the literature on the efficacy and toxicity of RHT. Evidence acquisition: This systematic review was registered with the PROSPERO database (Registration number: CRD42015025780) and was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. We queried PubMed, EMBASE, and Cochrane libraries. Two reviewers reviewed abstracts independently and a third reviewer arbitrated disagreements. The last search was performed on 28 August 2015. A descriptive analysis was performed and quality assessment was conducted using the Newcastle-Ottawa Quality Assessment Scale for observational studies, and the Cochrane Risk of Bias Assessment Tool for trials. Evidence synthesis: We identified 859 publications in the initial search, of which 24 met inclusion criteria for full-text review. Of these, we were able to obtain data on the outcomes of interest for 15 publications. Conclusions: The review underscores the limited nature of the evidence; definitive conclusions are elusive. However, the promising results of RHT in the setting of intravesical chemotherapy, chemotherapy and radiotherapy show a trend towards legitimate efficacy.

Lifestyle factors and health-related quality of life in bladder cancer survivors: a systematic review

PurposeDiet, physical activity, and smoking cessation are modifiable lifestyle factors that have been shown to improve health-related quality of life (HRQOL) in many cancer survivors. Our objective was to systematically review the literature on the associations between lifestyle factors, namely diet, physical activity, smoking status, and HRQOL in bladder cancer survivors.MethodsWe queried PubMed, EMBASE, and Cochrane libraries. Two reviewers reviewed abstracts independently, and a third reviewer arbitrated disagreements. A descriptive analysis was performed. Quality assessment was conducted using the Newcastle-Ottawa Quality Assessment Scale for observational studies and the Cochrane Risk of Bias Tool for clinical trials.ResultsWe identified 1167 publications in the initial search, of which 9 met inclusion criteria for full-text review. We were able to obtain data on the outcomes of interest for 5 publications. A total of 1288 patients who underwent treatment for bladder cancer were included. Three studies were observational by design and two were randomized controlled trials. Physical activity was addressed by 4 studies, smoking status by 2 studies, and diet by 1 study.ConclusionsThe review highlights the limited evidence around lifestyle factors and quality of life in bladder cancer survivors. There is some evidence for a positive association between HRQOL and physical activity, but insufficient evidence upon which to draw conclusions about the effects of consuming fruits and vegetables or non-smoking.Implications for Cancer SurvivorsThere is limited evidence to support a positive association between health-related quality of life and physical activity, but insufficient evidence upon which to base any conclusions about consumption of fruits and vegetables or smoking cessation in bladder cancer survivors.

High rates of venous thromboembolic events in patients undergoing systemic therapy for urothelial carcinoma: A systematic review and meta-analysis

BACKGROUND Patients undergoing systemic therapy for urothelial carcinoma (UC) are at increased risk for venous thromboembolic (VTE) events. The objective of the current study was to determine the rate of VTE events in patients undergoing systemic therapy for UC and assess factors affecting this rate. METHODS This study was registered with the PROSPERO database (CRD42015025774). We searched Pubmed, MEDLINE, EMBASE, The Cochrane Library, CINAHL, and Web of Science libraries through August 2014. As per PRISMA guidelines, 2 reviewers independently reviewed titles and abstracts. Disagreements were arbitrated by a third reviewer. After full text review, data were abstracted and pooled using a random effects model. Authors were contacted for clarification of data. To determine VTE risk factors, subgroup analyses and meta-regression were conducted. RESULTS We identified 3,635 publications in the initial search, of which 410 met inclusion criteria for full text review. Of these, we were able to obtain data on the outcome of interest for 62 publications. A total of 5,082 patients, of which 77% were male, underwent systemic therapy for UC, with 373 VTE events. The proportion of patients who had had prior surgery, chemotherapy, or radiation was 55%, 25%, and 9%, respectively. Fixed effects and random effects models were used to estimate the VTE rate, yielding event rates of 6.7% and 5.4%, respectively. CONCLUSIONS VTE occurs frequently in patients undergoing systemic therapy for UC. The VTE rate was affected by the country of origin, history of radiation, as well as by the systemic treatment class. The study was limited by the incomplete reporting of all variables of interest.

Urinary NID2 and TWIST1 methylation to augment conventional urine cytology for the detection of bladder cancer

BACKGROUND Abnormal methylation of urinary TWIST1 and NID2 conferred high sensitivity and specificity for the detection of urothelial carcinoma. OBJECTIVE We examine the performance of the urine-based TWIST1/NID2 methylation assay with the addition of urine cytology for the detection of urothelial carcinoma. MATERIALS AND METHODS A prospective multi-institutional study was conducted to assess the performance of a methylation assay for patients with hematuria or under surveillance for non-muscle invasive bladder cancer (NMIBC). All patients underwent cystoscopy, a methylation assay, and cytology. Receiver operator characteristic (ROC) curves were constructed for cytology alone, the methylation assay alone, and a combined model. Areas under the curve (AUC) were compared using likelihood ratio tests. RESULTS A total of 172 patients were enrolled (37% for hematuria and 63% NMIBC). The AUC for cytology alone with equivocal cytologies positive was 0.704, and improved to 0.773 with the addition of the DNA methylation assay (p < 0.001). When the equivocal cytologies were considered negative, the AUC improved from 0.558 to 0.697 with the addition of the DNA methylation assay (p = 0.003). CONCLUSIONS Addition of a TWIST1/NID2-based DNA methylation assay adds diagnostic value to urine cytology and the model is sensitive to the classification of equivocal cytology.