TIME TO CHANGE OUR APPROACH TO HIGH-RISK NONMUSCLE-INVASIVE BLADDER CANCER MANAGEMENT IN THE UNITED KINGDOM? OBSERVATIONS FROM THE BRITISH ASSOCIATION OF UROLOGICAL SURGEONS CANCER REGISTRY

摘要

High-risk nonmuscle-invasive bladder cancer (HRNMIBC) is a clinical definition that attempts to distinguish tumours with the potential for progression to invasion from those with an indolent nature. This definition encompasses all poorly differentiated nonmuscle-invasive tumours (grade 3), those invading the lamina propria (T1) and carcinoma in situ (CIS). It accounts for 10-15% of all new bladder cancers within the UK [1]. Most guidelines suggest the initial management of HRNMIBC is with intravesical BCG [2]. This recommendation is based on Level 1 evidence that maintenance BCG reduces recurrence and delays or possibly prevents progression [3]. However, few patients complete the full course of maintenance BCG (16-33%) [4] and few cases within these meta-analyses were of high-grade disease (e.g. 8% [3]). Progression to muscle invasion occurs despite BCG in 9.8-53% of patients [5,6]. The variation in reported progression rates reflects differences in tumour inclusion criteria and the duration of follow-up. The highest progression rates are seen in series with the longest follow-up and only high-risk tumours [6,7]. Consequently, authors have suggested 'early' or 'primary' radical cystectomy (RC) for patients with HRNMIBC that are fit enough to undergo radical pelvic surgery [8]. Proponents of this approach cite the evidence that primary RC is beneficial in terms of disease-specific survival [9], the low mortality and morbidity of modern RC [10], and the increased quality-of-life years and decreased cost of RC when compared to BCG [11,12]. Furthermore, oncological outcomes from RC for BCG-refractory disease appear worse than those for de novo invasive tumours [13]. The counter-argument is that HRNMIBC does not always progress to invasion and that intravesical BCG therapy may allow a significant number of patients to preserve their bladder in the long term, whilst avoiding the risks of radical pelvic surgery [14,15].