title: Prospective study of leukocyte count as a predictor of incident breast, colorectal, endometrial, and lung cancer and mortality in postmenopausal women.
abstract: BACKGROUND
  The immune system and inflammation are implicated in the pathogenesis of cancer. Prospective studies linking biomarkers of inflammation with cancer incidence and mortality have been inconclusive.
  
  
  METHODS
  To determine whether there is an independent association of white blood cell (WBC) count with incident cancer in postmenopausal women, a prospective cohort study was performed at 40 US clinical centers involving 143,748 postmenopausal women aged 50 to 79 years who were free of cancer at baseline and were enrolled in the Women's Health Initiative. The main outcome measures were incident invasive breast, colorectal, endometrial, and lung cancer.
  
  
  RESULTS
  In multivariate models, there was a graded association of WBC count with incidence of all 4 types of cancer. Compared with the lowest quartile of WBC count (2.50-4.79x10(9) cells/L), women with a WBC count in the upper quartile (6.80-15.00x10(9) cells/L) had a statistically significantly higher risk of invasive breast cancer (hazard ratio [HR], 1.15; 95% confidence interval [CI], 1.04-1.26), colorectal cancer (HR, 1.19; 95% CI, 1.00-1.41), endometrial cancer (HR, 1.42; 95% CI, 1.12-1.79), and lung cancer (HR, 1.63; 95% CI, 1.35-1.97). The findings were similar when cancers that occurred during the first 2 years of follow-up were excluded. Statistically significant associations remained for invasive breast cancer and endometrial cancer when the analyses were limited to nonsmokers. The WBC count was also statistically significantly associated with breast cancer, lung cancer, and overall cancer mortality.
  
  
  CONCLUSIONS
  Postmenopausal women with higher WBC counts have a higher risk of incident invasive breast, colorectal, endometrial, and lung cancer, as well as a higher risk of breast, lung, and overall cancer mortality.
authors: HealthPartners Research Foundation, PO Box 1524, Mail Stop 21111R, Minneapolis, MN 55440-1524, USA. Karen.L.Margolis@HealthPartners.com
authors: Karen L
authors: KL
authors: Margolis
authors: Rebecca J
authors: RJ
authors: Rodabough
authors: Cynthia A
authors: CA
authors: Thomson
authors: Ana Maria
authors: AM
authors: Lopez
authors: Anne
authors: A
authors: McTiernan
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000401:mortality; D015179:Colorectal Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000401:mortality; D016889:Endometrial Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000401:mortality; D005260:Female; D006801:Humans; D015994:Incidence; D007958:Leukocyte Count; D008175:Lung Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000401:mortality; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D017698:Postmenopause / Q000097:blood; D011237:Predictive Value of Tests; D011446:Prospective Studies