Microscopic hematuria as a screening marker for urinary tract malignancies

Although a mass screening urinalysis is a widely accepted procedure, it has not yet been shown if microhematuria is an appropriate and useful screening marker for urologic malignancies.

(1) The incidence of hematuria was studied in 113 patients with renal cell carcinoma (RCC), 185 with bladder carcinoma and 51 with renal pelvic or ureteral carcinoma. The association of the T stage with the intensity of hematuria in each malignancy was also examined. (2) In 823 asymptomatic adults with microhematuria, the prevalence of these malignancies was studied retrospectively to find the positive predictive value (PPV).

(1) The incidence of hematuria was 35% for RCC, including gross and microhematuria. Advanced RCC (T3 and T4) were diagnosed more frequently in the gross hematuria group than in the microhematuria and no hematuria groups. In contrast, the incidence of hematuria was 94% for urothelial carcinomas either in the upper urinary tract or in the bladder. There was no significant difference in the T stage nor grade between the gross hematuria group and the microhematuria group. (2) Regarding asymptomatic microhematuria, the PPV was 1.7% (14 cases) for bladder carcinoma, 0.4% (3 cases) for ureteral/renal pelvic carcinoma and 0.2% (2 cases) for RCC. In men aged 50 years or older, PPV was 6.2% for urothelial carcinomas. In 14 cases of bladder carcinoma, 3 cases showed muscle invasion.

Microhematuria is an appropriate screening marker for urothelial carcinomas, particularly in elderly men, but not for RCC. However, it is unlikely that a mass screening urinalysis using a single voided urine sample would contribute to earlier detection of bladder carcinoma.