Oncology - Bladder, Renal, Test
Mid-Atlantic Section 76th Annual Meeting
Introduction & Objective : Bladder cancer is the fifth most commonly diagnosed cancer in the US in 2018. Unfortunately, it also happens to be one of the most expensive cancers to treat due to the frequent surveillance required. Practically, a urinary biomarker with both high sensitivity and specificity for urothelial carcinoma (UC) could decrease the number of surveillance cystoscopies. The goal of the study was to determine the accuracy of cytology as compared CxBladder in detecting UC of the bladder confirmed by cystoscopy and biopsy.
This was a single institution, retrospective chart review study of all patients 18 years of age or older who were tested with urinary cytology and CxBladder (Detect or Monitor) as part of a standard bladder cancer surveillance protocol between 10/2013 through 02/2017. Urinary cytology was defined as positive if suspicious for malignancy or urothelial carcinoma. It was defined as negative if negative for malignancy or one of the three atypical subtypes including atypical suspicious for neoplasm. Sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) at the 95% confidence interval were used to assess the validity and reliability of above urinary biomarkers to detect the presence or absence of UC compared to the gold standard, cystoscopic examination +/- biopsies. Analyses were performed in SAS 9.4 (SAS Institute, Cary, NC).
Results : A total of 223 urine samples were collected from patients undergoing surveillance for UC. 195 cytology reports and 173 CxBladder reports (126 for Detect, and 47 for Monitor) were included in the analysis. The results for the urinary biomarkers are outlined in Table 1. Urinary cytology had a sensitivity of 39.2% and a specificity of 96.4%. CxBladder Monitor had the best sensitivity of 66.7%.
The best NPV was recorded by CxBladder Monitor and indicates 93.3% of patients who tested negative truly did not have recurrence of urothelial carcinoma.
CxBladder Monitor has overall superior sensitivity and NPV compared to cytology, which makes it a better surveillance adjunct for patients with history of UC of bladder. This urinary biomarker improves our ability to “rule-out” disease recurrence non-invasively.