Active surveillance for non-muscle invasive bladder cancer.

Most of low grade (LG) bladder tumors will experience disease recurrence and very few of them (<2%) will experience disease progression. Therefore active surveillance (AS) for LG non-muscle invasive bladder cancer (NMIBC) has emerged. The goal of our study was to provide a literature review of AS for LG NMIBC including inclusion criteria, modalities and oncological outcomes. We conducted a systematic review (registered in PROSPERO: CRD42018102935) using MEDLINE and EMBASE between June 2018 and August 2018 with the following terms: LG, NMIBC, AS, urothelial neoplasm. Overall, 6 studies that reached our scope of review were included cumulating 403 patients with 2 prospective trials. Inclusion criteria were: recurrent LG (G1 and G2) Ta or T1 NMIBC, with a negative cytology, a low volume (<10 mm) and low number (<5) of tumors. Cystoscopy every 3 months during the first 2 years and every 6 months afterwards were required. AS dropout criteria were presence of tumor-related symptoms, a positive cytology, a modification of tumor morphology or size and patient's request. Pooled data showed an overall 65% reclassification rate where 15% of patients were reclassified based on grade and 10% on stage with a median follow-up of 32 months (IQR, 24-42 months). Only one study reported on progression to MIBC in 4 patients out of 186 (2%). Most of patients enrolled in an AS protocol for recurrent LG NMIBC will undergo a TURBT eventually. Many patients may be eligible to this therapeutic approach but current knowledge does not support its use in daily practice outside of a clinical trial.