Non-muscle invasive bladder cancer cystoscopic surveillance: from overuse to underuse and non-adherence impact

The burden of non-muscle-invasive bladder cancer (NMIBC) surveillance is well known, including 8% surgical complication with up to 3% death, adding to anxiety, discomfort and health care expenditures (1-4).

Schroeck et al. found in a low-grade Ta (AJCC) NMIBC retrospective cohort study that compared to guidelines recommended (1 to 3 cystoscopies) surveillance, patients that underwent frequent cystoscopies (>3, n=798, 77%) during the first 2 years after diagnosis had significantly doubled the transurethral resections (TUR) with no impact on bladder cancer progression and death (3% at 5 years) (5).

On the other hand, a subtle and contradicting result obtained in the same data blows the mind of the most attentive readers: after sensitivity analysis for intermediate-risk disease, earlier muscle-invasive progression or mortality significantly occurred among those with more than recommended surveillance (3% at 4.0 years vs. 3% at 6.2 years; HR 2.13; 95% CI, 1.06–4.27) (5) and it is likely because of unobserved confounding such as tumor size, multifocality, early and frequent recurrence, which were neglected in the study and may put patients at a higher risk warranting high-risk similar approach (6).

Moreover, about 60% of NMIBC are considered intermediate or high risk based on pathology, representing the bulk of a continuum (7). Also in the high-risk spectrum of the NMIBC, Datovo et al. recently described 18% of cystoscopy non-adherence in the first 3 years of follow-up and among potential related factors (disease and patient characteristics and behaviors) and eventual consequences, cystoscopy non-adherence was significantly associated with less urinary cytology and 2.33 HR for progression, (95% CI, 1.18–4.59) (8).

While the need for frequent and costly cystoscopic surveillance is thought to be the main NMIBC cost burden, Mossanen et al. comparing expenditures across risk categories using mathematical modeling found that while cystoscopy contributes to considerable expenses, disease progression to MIBC was the primary cost driver, mainly in the high-risk disease (9).

In fact, the data comparing different surveillance regimens for NMIBC are limited, with relatively short follow-up and very underpowered, warranting further refinement and acknowledgement of the natural heterogeneity of NMIBC (10-12).

While it looks undisputable that the main forces driving the surveillance frequencies in the real world are related to the attending physician choices, usually based on identification of perceptive risk factors, part of chronic unobserved confounding in retrospective studies, patients also interfere by cystoscopy non-adherence (8) or by demanding a very high level of sensitivity before they would be willing to accept an alternative to cystoscopy for surveillance (13).

The above-mentioned paradigm shifting studies illustrate a boiling arena and promissory future with clear potential for clinical and economic optimizations, refining care quality and sustainability (14).

Cystoscopic surveillance is still the gold standard strategy to the inherently highly recurrent and naturally heterogenic NMIBC and depending on surveillance intensity, it might be accountable not only for impacting on disease control, but for costs ranging from potentially unnecessary procedures, anxiety, discomfort and health care expenditures in one of the most expensive cancers from diagnosis to death.

The lack of data regarding ideal follow-up alongside the wide NMIBC spectrum and its impact makes the topic very important, instigating future studies to improve surveillance and to further understand cystoscopy overuse, underuse and adherence.

Ethical Statement: The author is accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.