What is the relative risk of urologic malignancy in microscopic hematuria patients after negative evaluation? A long-term population-based retrospective analysis of 8465 patients.

OBJECTIVE

To evaluate whether microscopic hematuria (MH) patients with a negative initial evaluation have an elevated risk for urinary carcinoma.

METHODS

This is a population-based retrospective study with a matched control identified 8465 adults with an MH ICD code, an initial negative urinary malignancy work-up of cystoscopy and CT urography, and at least 35 months of clinical care. 8465 hematuria naïve controls were age, gender, and smoking status matched. Subsequent coding of non-prostatic urinary cancer, or any following hematuria codes: additional microscopic unspecified or unspecified hematuria, and gross hematuria was obtained. Χ2 tests were performed.

RESULTS

There was no statistically significant difference in urinary malignancy rates (p > 0.05). Any urinary cancer: cases 0.74% (63/8465; 95% CI 0.58-0.95%)/controls 0.83% (71/8465; 95% CI 0.66-1.04%%) (p = 0.54); bladder: 0.45%/0.47% (p = 0.82); renal: 0.31%/0.38% (p = 0.43); ureteral: 0.01%/0.02% (p = 0.56). Subsequent gross hematuria in both males and females increased the odds of cancer: males 2.35 (p = 0.001; CI 1.42-3.91); females 4.25 (p < 0.001; CI 1.94-9.34). Males without additional hematuria had decreased odds ratio: 0.32 (p = 0.001; CI 0.16-0.64). Females without additional hematuria 0.58 (p = 0.19; CI 0.26-1.30) and both genders with additional unspecified hematuria/microscopic hematuria males 1.02 (p = 0.97; CI 0.50-2.08) and females 1.00 (p = 0.99; CI 0.38-2.66) did not have increased odds ratios (p > 0.05).

CONCLUSION

MH patients with initial negative evaluation have a subsequent urologic malignancy rate of less than 1% and likely do not need further urinary evaluation unless they develop gross hematuria.