The IDENTIFY study aims to determine contemporary urinary tract cancer rates and diagnostic test performance in patients referred to secondary care with suspected urothelial cancer.
IDENTIFY is the largest ever prospective, international, multi-centre study of patients referred to secondary care, with or without haematuria, for the investigation of suspected urinary tract cancer. Patient demographics, presenting features and diagnostic test results were recorded. Prevalence rates were calculated for each subtype of urological cancer and diagnostic test accuracies were calculated.
Over 10,000 patient records were collected from 111 hospitals in 28 countries (Dec 2017 – Oct 2018). 63.3% presented with visible haematuria [VH], 31.6% with non-visible haematuria [NVH] and 5.1% without haematuria [NH]. The prevalence of bladder cancer [BC] overall was 14.2%; 18.1% in VH, 3.7% in NVH and 26.6% in NH. 81.5% of bladder cancers presented with VH. Upper tract urothelial cancer [UTUC] prevalence was 1%, renal cell carcinoma [RCC] 0.9% and prostate cancer 1.2%. BC and UTUC prevalence peaked in the 70-79 year age group and were more common in men. Variables significantly associated with BC included type of haematuria, age, smoking history, anticoagulation, storage urinary tract symptoms and having had >1 episode of VH (25.5%) vs. only 1 (17.9%). UTUC was significantly associated with type of haematuria, age, smoking history and anticoagulation. The rate of BC found in those with culture proven urinary tract infection [UTIs] was 7.0%, which was significantly lower than BC rate in those without UTI (19.7%). The diagnostic performance of ultrasound [US] and Computed Tomography [CT] is given in Table 1.
| Imaging Modality |
Sensitivity | Specificity | Positive Predictive Value | Negative Predictive Value | |
| Bladder Cancer |
US | 77.8% (95% CI 74.4%-81.0%) | 93.5% (95% CI 92.7%-94.3%) | 67.8% (95% CI 64.9%-70.5%) | 96.0% (95% CI 95.5%-96.6%) |
| Contrast CT | 80.5% (95% CI 77.3%-83.4%) | 92.3% (95% CI 91.3%-93.3%) | 71.5% (95% CI 68.7%-74.1%) | 95.2% (95% CI 94.4%-95.9%) | |
| UTUC | US | 42.5% (95% CI 27.0%-59.1%) | 97.7% (95% CI 97.3%-98.1%) | 12.7% (95% CI 12.4%-27.7%) | 99.5% (95% CI 99.4%-99.7%) |
| CT Urogram | 95.7% (95% CI 88.0%-99.1%) | 94.4% (95% CI 93.5%-95.2%) | 26.8% (95% CI 24.0%-29.8%) | 99.9% (95% CI 99.7%-99.97%) |
IDENTIFY provides contemporary cancer detection rates in a global population alongside diagnostic test performance for each cancer type. The extensive data will allow a personalised approach to haematuria investigations and improve shared decision-making by developing predictive models to optimise cancer detection. These patient-specific pathways will reduce patient and healthcare resource burdens.