Predictors of genitourinary malignancy in patients with asymptomatic microscopic hematuria

To report the incidence of genitourinary malignancy and identify associated risk factors in patients undergoing urologic evaluation for asymptomatic microscopic hematuria (AMH) according to the 2012 American Urologic Association guidelines.

A retrospective institutional review of patients who underwent evaluation for AMH between 2012 and 2015 was conducted. Covariates analyzed included age, sex, smoking status, history of other malignancy, history of pelvic irradiation, presence of irritative voiding symptoms, use of anticoagulation, number of red blood cells on microscopic urinalysis, and guideline adherence. Univariate analysis was performed to explore the association between these risk factors and the presence of genitourinary malignancy.

Of the 1,049 patients analyzed with AMH, urologic malignancy was diagnosed in 12 patients (1.1%), including 1 upper-tract urothelial cancer, 5 renal tumors, and 6 bladder tumors. All patients with malignancy were over 50 years old. Older age, male sex, smoking history, and irritative voiding symptoms were associated with malignancy on univariate analysis.

Our data adds to the growing evidence that the incidence of malignancy among patients with AMH is low. Risk factors associated with urinary tract cancer are male sex, age>50 years, smoking history, and irritative voiding symptoms. Further prospective, randomized trials would be useful for developing a more tailored screening protocol for low-risk patients.