OBJECTIVE: To assess the contemporary inter‐institutional accuracy of urinary cytology in predicting the recurrence of transitional cell carcinoma (TCC) of the bladder, in a large multi‐institutional cohort from four continents, as cystoscopy and urinary cytology represent the ‘gold standards’ for surveillance of TCC recurrences, but the ability of cytology to predict recurrence varies. PATIENTS AND METHODS: Ten institutions contributed 2542 patients with a history of superficial TCC, of whom 898 had TCC recurrence. Age‐ and gender‐adjusted logistic regression models were used to evaluate the association between urine cytology and TCC recurrence. The predictive accuracy derived from the logistic regression model was tested using the area under the receiver operating characteristic curve. The resulting predictive accuracy estimates were internally validated with 200 bootstrap re‐samples. RESULTS: The mean (range across institutions) age of the patients was 65 (48–69) years and 75 (67–87)% were men. Cytology was positive in 19 (10–38)% of patients; recurrence was identified in 35 (27–54)% of patients. The sensitivity was 38–65% across institutions. Urinary cytology varied significantly in its ability to predict recurrence of bladder cancer. Institution‐specific predictive accuracy adjusted for gender and age was 0.627–0.893. Stratifying by grade and stage only partly attenuated the discrepancies between centres. CONCLUSIONS: The variability of urinary cytology results was very appreciable among the 10 centres and ranged from poor (63%) to excellent (89%).

We developed and validated nomograms that accurately predict disease recurrence and progression in patients with Ta, T1, or CIS transitional cell carcinoma (TCC) of the bladder using a large international cohort. Univariate and multivariate logistic regression models targeted histologically confirmed disease recurrence, and focused on 2,542 patients with bladder TCC from 10 participating centers. Variables consisted of pre-cystoscopy voided urine Nuclear Matrix Protein 22 (NMP22) assay, urine cytology, age and gender. Resulting nomograms were internally validated with bootstrapping. Nomogram performance was explored graphically with Loess smoothing plots. Overall 957 patients had recurrent TCC. Tumor grade and stage was available for 898 patients, including 24% grade I, 43% grade II, and 33% grade III; 45% stage Ta, 32% T1 and/or CIS, and 23% T2 or greater. Bootstrap corrected predictive accuracy for any TCC recurrence was 0.842; grade III Ta/T1 or CIS was 0.869; and T2 or higher stage TCC of any grade was 0.858. Virtually perfect performance characteristics were observed for the nomograms predicting any TCC recurrence or grade III Ta/T1 or CIS. The nomogram predicting T2 or higher stage TCC overestimated the observed probability for predicted values greater than 45%. We developed and internally validated nomograms that incorporate urinary NMP22, cytology, age and gender to predict with high accuracy the probability of disease recurrence and progression in patients with Ta, T1, and/or CIS bladder TCC. These nomograms could provide a means for individualizing followup in patients with Ta, T1, CIS bladder TCC.

We assessed variability in the diagnostic performance of NMP22 for detecting recurrence and progression in patients with Ta, T1, and/or CIS transitional cell carcinoma of the bladder in a large international cohort. NMP22 voided urine levels were measured in 2,871 patients who underwent office cystoscopy for monitoring previous stage Ta, T1 and/or CIS transitional cell carcinoma at 12 participating institutions. Patient characteristics varied considerably among institutions. Overall 1,045 patients (36.4%) had recurrent transitional cell carcinoma (range across institutions 13.6% to 54.3%). Median NMP22 was 5.5 U/ml (range across institutions 2.5 to 18.8). Of the patients 33.5% had grade III tumors (range across institutions 20.6% to 54.0%) and 22.4% had muscle invasive tumors (range across institutions 3.2% to 38.2%). Area under the ROC curve for bladder TCC detection was 0.735 (95% CI 0.715 to 0.755, range across institutions 0.676 to 0.889). The manufacturer recommended cutoff of 10 U/ml detected 57% of cases with a 19% false-positive rate. AUC for grade III and stage T2 or greater disease was 0.806 (95% CI 0.780 to 831) and 0.864 (95% CI 0.839 to 0.890), respectively. For each NMP22 cutoff NMP22 had higher sensitivity for detecting grade III and stage T2 or greater bladder transitional cell carcinoma than for detecting any cancer. No optimal cutoffs for detecting any or aggressive bladder transitional cell carcinoma could be derived based on NMP22 values. There is a substantial degree of heterogeneity in the diagnostic performance of NMP22 applied to populations from different institutions. There is no clearly defined NMP22 cutoff but there is a continuum of risk for recurrence and progression.