The natural history of low-risk non-muscle-invasive bladder cancer: a collaborative multi-centre study.

International guidelines vary in terms of their definition and recommendation for management of low-risk non-muscle-invasive bladder cancer (LRNMIBC). The ideal management for this large subset of bladder cancer patient remains unclear.

To evaluate long-term outcomes of patients with LRNMIBC. As a secondary objective, to assess for intergroup heterogeneity in disease-specific outcomes between G1 and G2LG diseases.

A multi-centre, retrospective study of patients who met the 2015 NICE definition of LRNMIBC. Timeline of diagnosis ranged from 01/01/2012 to 30/06/2016.

A total 390 patients had available follow-up data (G1: 142, G2LG: 249). Over a median follow-up time of 36 months (IQR 25-50), 29.2% of the patients developed a recurrence. G2LG patients were statistically more likely to develop a recurrence (G1: 26.8%, G2LG: 33.7%, p < 0.05). 51.8% of recurrences occurred after 1 year of surveillance. Progression to high-grade disease occurred in 1.8% (n = 7, G1: 3, G2LG: 4) and a further 1.0% (n = 4, G1:3, G2LG: 1) of patients developed muscle-invasive bladder cancer (MIBC).

The majority of recurrences occurred after 1 year of surveillance. The risk of disease progression was low; however, this was observed in a cohort of patients with regular cystoscopic follow-up. The risk may be higher if patients were pre-maturely discharged. If a 5-year surveillance programme were to be followed, 96.5% of recurrences would be captured. Lastly, there appears to be intergroup heterogeneity within LRNMIBC with G2LG patients having a statistically higher risk of recurrence compared to G1.

International urology and nephrology. 2022 Jun 27 [Epub ahead of print]

A Jaffer, M Lee, O Khalil, M Raslan, S Rai, A Kozan, M Hannah, A Al-Mitwalli, M Bryan, M Simms, M Dooldeniya, J Wilson, S R JainChahal

Leeds Teaching Hospitals NHS Trust, Leeds, UK. ., Leeds Teaching Hospitals NHS Trust, Leeds, UK., Hull University Teaching Hospital NHS Trust, Hull, UK., Calderdale and Huddersfield NHS Trust, Huddersfield, UK., Mid Yorkshire Hospitals NHS Trust, Wakefield, UK., York Teaching Hospital NHS Trust, York, UK.