ABSTRACT
BACKGROUND: Hematuria is a cardinal symptom of urinary tract cancer and would require further investigations. OBJECTIVE: To determine the ability of renal bladder ultrasound (RBUS) with the Hematuria Cancer Risk Score (HCRS) to inform cystoscopy use in patients with hematuria. DESIGN, SETTING, AND PARTICIPANTS: The development cohort comprised 1984 patients with hematuria from 40 UK hospitals (DETECT 1; ClinicalTrials.gov: NCT02676180) who received RBUS. An independent validation cohort comprised 500 consecutive patients referred to secondary care for a suspicion of bladder cancer. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Sensitivity and true negative of the HCRS and RBUS were assessed. RESULTS AND LIMITATIONS: A total of 134 (7%) and 36 (8%) patients in the development and validation cohorts, respectively, had a diagnosis of urinary tract cancer. Validation of the HCRS achieves good discrimination with an area under the receiver operating characteristic curve of 0.727 (95% confidence interval 0.648-0.800) in the validation cohort with sensitivity of 95% for the identification of cancer. Utilizing the cutoff of 4.500 derived from the HCRS in combination with RBUS in the development cohort, 680 (34%) patients would have been spared cystoscopy at the cost of missing a G1 Ta bladder cancer and a urinary tract cancer patient, while 117 (25%) patients would have avoided cystoscopy at the cost of missing a single patient of G1 Ta bladder cancer with sensitivity for the identification of cancer of 97% in the validation cohort. CONCLUSIONS: The HCRS with RBUS offers good discriminatory ability in identifying patients who would benefit from cystoscopy, sparing selected patient cohorts from an invasive procedure. PATIENT SUMMARY: The hematuria cancer risk score with renal bladder ultrasound allows for the triage of patients with hematuria who would benefit from visual examination of the bladder (cystoscopy). This resulted in 25% of patients safely omitting cystoscopy, which is an invasive procedure, and would lead to health care cost savings.
