To assess Urologists' ability to predict the grade and stage of new bladder cancers from the cystoscopic features alone.
We conducted a prospective clinical study on consecutive patients undergoing Transurethral Resection of Bladder Tumour (TURBT) for new bladder cancers. Using only cystoscopic tumour morphology at the time of initial TURBT, 3 Urology consultants predicted the grade and stage, recording this on a proforma along with tumour features. Predictions were compared with assessments by uro-pathologists, blinded to the clinical prediction. We analysed the accuracy in: (a) predicting exact grade and stage of the cancer; (b) differentiating between low and high grade cancers; (c) discerning between Ta, T1 and T2 cancers.
Of 248 patients, 224 were suitable for analysis. The positive predictive values (PPV) for low and high grade cancers were 85.8% and 71.3%, respectively. The overall likelihood of a consultant predicting high grade cancers as being low grade was 16/83 (19.3%). When tumours were large (>30mm), this likelihood dropped significantly to 7.3% (4/55) (OR=3.1, 95%CI=1.0-9.7, p=0.04). Non-muscle invasive and muscle invasive cancers were predicted accurately in 93.4% and 85.2% patients, respectively. Six of 161 (3.7%) tumours predicted to be NMIBC were actually muscle invasive on histology.
For clinical purposes, in newly presenting patients with bladder cancer, Urologists' appear to reliably predict lower grade and muscle invasive disease, confirming widely held belief. This allows for appropriate and efficient use of surgical expertise, available technology and entry into clinical trials selecting on the basis of pre-histology risk categories.
Urology. 2017 Aug 14 [Epub ahead of print]
Paramananthan Mariappan, Victoria Lavin, Chu Qin Phua, Shahid Aziz Anwar Khan, Roland Donat, Gordon Smith
Edinburgh Urological Cancer Group, Department of Urology, Western General Hospital, Edinburgh, EH4 2XU, United Kingdom. Electronic address: ., Edinburgh Urological Cancer Group, Department of Urology, Western General Hospital, Edinburgh, EH4 2XU, United Kingdom.