This study showed that a bladder-sparing procedure was not inferior to surgery in terms of disease-free survival, and is therefore a good alternative to a radical cystectomy and may possibly be presented more prominently (in guidelines) as a treatment option. This result is also supported by other recent studies. Nevertheless, it remains difficult to convince everyone of the results of such a non-randomized observational study because it is by definition low level evidence are considered.
I am convinced that observational studies have a place in the research field in which the effectiveness of treatments is investigated. Sometimes because a randomized study is not always possible, for example because you need too many patients or for ethical, logistical or cost reasons. In addition, the results from the clinical trials do not say everything because they were usually conducted in a selective patient group with favorable prognostic characteristics. It is therefore good to evaluate the effectiveness of a treatment based on, in addition to the randomized studies real world data in an unselected patient population that also includes less fit patients.’
