title: Evaluation of microscopic hematuria and risk of urologic cancer in female patients.
abstract: BACKGROUND
  Urologic cancer has a lower prevalence in women compared with men; however, there are no differences in the recommended evaluation for women and men with microscopic hematuria.
  
  
  OBJECTIVE
  The purpose of this study was to identify risk factors that are associated with urologic cancer in women with microscopic hematuria and to determine the applicability of a hematuria risk score for women.
  
  
  METHODS
  We conducted a retrospective cohort study within an integrated healthcare system in Southern California. All urinalyses with microscopic hematuria (>3 red blood cells per high-power field) that were performed from 2009-2015 were identified. Women who were referred for urologic evaluation were entered into a prospective database. Clinical and demographic variables that included the presence of gross hematuria in the preceding 6 months were recorded. The cause of the hematuria, benign or malignant, was entered into the database. Cancer rates were compared with the use of chi-square and logistic regression models. Adjusted risk ratios of urologic cancer were estimated with the use of multivariate regression analysis. We also explored the applicability of a previously developed, gender nonspecific, hematuria risk score in this female cohort.
  
  
  RESULTS
  A total of 2,705,696 urinalyses were performed in women during the study period, of which 552,119 revealed microscopic hematuria. Of these, 14,539 women were referred for urologic evaluation; clinical data for 3573 women were entered into the database. The overall rate of urologic cancer was 1.3% (47/3573). In women <60 years old, the rate of urologic cancer was 0.6% (13/2053) compared with 2.2% (34/1520) in women ≥60 years old (P<.01). In women who reported a history of gross hematuria, the rate of urologic cancer was 5.8% (20/346) compared with a 0.8% (27/3227) in women with no history of gross hematuria (P<.01). In multivariate analysis, > 60 years old (odds ratio, 3.1; 95% confidence interval, 1.6-5.9), a history of smoking (odds ratio, 3.2; 95% confidence interval, 1.8-5.9), and a history of gross hematuria in the previous 6 months (odds ratio, 6.2; 95% confidence interval, 3.4-11.5) were associated with urologic cancers. A higher microscopic hematuria risk score was associated with an increased risk of cancer in this test cohort (P<.01). Women in the highest risk group had a urologic cancer rate of 10.8% compared with a rate of 0.5% in the lowest risk group.
  
  
  CONCLUSIONS
  In this female population, >60 years old and a history of smoking and/or gross hematuria were the strongest predictors of urologic cancer. Absent these risk factors, the rate of urologic cancer did not exceed 0.6%. A higher hematuria risk score correlated significantly with the risk of urologic cancer in this female test cohort.
authors.affiliation: University of California San Diego & Kaiser Permanante, San Diego Medical Center, San Diego, CA.
authors.forename: Quinn K
authors.initials: QK
authors.lastname: Lippmann
authors.affiliation: Kaiser Permanente, Pasadena, CA.
authors.forename: Jeff M
authors.initials: JM
authors.lastname: Slezak
authors.affiliation: Kaiser Permanente, San Diego, CA. Electronic address: Shawn.a.menefee@kp.org.
authors.forename: Shawn A
authors.initials: SA
authors.lastname: Menefee
authors.affiliation: Kaiser Permanente, Fontana, CA.
authors.forename: Casey K
authors.initials: CK
authors.lastname: Ng
authors.affiliation: Kaiser Permanente, Orange County, CA.
authors.forename: Emily L
authors.initials: EL
authors.lastname: Whitcomb
authors.affiliation: Kaiser Permanente, Downey, CA.
authors.forename: Ronald K
authors.initials: RK
authors.lastname: Loo
mesh_terms: D000328:Adult; D000367:Age Factors; D002140:California / Q000453:epidemiology; D015331:Cohort Studies; D016208:Databases, Factual; D005260:Female; D006417:Hematuria / Q000453:epidemiology* / Q000652:urine; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology*; D014571:Urologic Neoplasms / Q000453:epidemiology* / Q000652:urine
keywords: hematuria; urologic cancer