Microscopic hematuria and pelvic ultrasonography could rule out flexible cystoscopy during surveillance for T1-low grade non-muscle invasive bladder cancer

Abstract

Purpose Cystoscopy (rigid/flexible [FC]) is the standard surveillance tool for non-muscle invasive bladder cancer (NMIBC). Nevertheless, it has its drawbacks. The objective of this study is to evaluate the performance of microscopic hematuria (MH), abdominal ultrasonography (US), and urine cytology (UC) as potential substitutes for FC in patients with T1-low-grade (T1-LG) NMIBC. Methods Over a 12-month period, patients attending our tertiary referral center for T1-LG NMIBC follow-up underwent urine analysis for MH and UC, and then US and FC were performed as outpatient surveillance procedures. Those with positive findings underwent inpatient rigid cystoscopy under anesthesia and biopsy. The negative predictive values (NPV) and sensitivity of different combinations of MH, UC, US, and FC were compared with the standard histopathology. Results In 218 evaluated patients, FC had the highest NPV (97.9%). However, this figure showed no statistically significant difference if compared with the combination of negative MH and US (93.8%) (difference = 0.04, p = 0.1) or the combination of MH, US, and UC (94.9%) (difference = 0.03, p = 0.2). The reported sensitivity results were similarly comparable between FC (94.2%) and the aforementioned combinations (90.4% and 92.3%; differences: 0.038 and 0.019; p = 0.4 and 0.7, respectively). Conclusions During the surveillance of NMIBC for patients diagnosed with T1-LG disease, the combination of MH/US has comparable sensitivity and NPV with FC. This non-invasive combination could be considered the first station that might preclude the need for FC in a considerable percentage of this group of patients.