Detrusor Muscle in the First, Apparently Complete Transurethral Resection of Bladder Tumour Specimen Is a Surrogate Marker of Resection Quality, Predicts Risk of Early Recurrence, and Is Dependent on Operator Experience

Background: An European Organisation for Research and Treatment of Cancer analysis of multicentre trials found significant interinstitutional variability in recurrence rates at first follow-up cystoscopy (RR-FFC) and attributed this to variable transurethral resection of bladder tumour (TURBT) quality. Objective: To determine whether resection of detrusor muscle (DM) in the first, apparently complete TURBT is a surrogate marker of quality and whether the presence of DM is dependent on a surgeon's experience. Design, setting, and participants: Over a 2-yr period, patients with new bladder tumours that were judged to have been completely resected were recruited from our prospectively maintained bladder tumour database. Strict exclusion criteria were applied. Measurements: Prospectively recorded tumour size, tumour multiplicity, surgeon category, DM status, grade and stage of tumour, and findings at first follow-up cystoscopy (at 3 mo) and at early re-TURBT were evaluated. Surgeons were stratified into seniors (consultants and year 5 or year 6 trainees) and juniors (trainees lower than year 5). Early recurrence (for calculating RR-FFC) was defined as pathologically confirmed tumour on early re-TURBT or recurrence at the first follow-up cystoscopy. Logistic regression multivariate analyses were carried out to determine associations between variables. Results and limitations: In a total of 356 patients, DM was present in 241 patients (67.7%). Multivariate analyses revealed that large tumours, high-grade tumours, and surgery by senior surgeons was independently associated with the presence of DM in the resected specimens. The RR-FFCs when DM was absent and present were 44.4% and 21.7%, respectively (odds ratio: 2.9; 95% confidence interval: 1.6-5.4; p = 0.0002). The absence of DM and resection by less experienced surgeons independently predicted a higher RR-FFC. This association was also seen in small and low-grade tumours. The number of patients in this study appears modest, and further validation may be required. Conclusions: DM absence or presence in the first, apparently complete TURBT specimen appears to be a surrogate marker of resection quality by independently predicting the RR-FFC, which is also dependent on surgeon experience.