Add high WBC count to the list of risk factors for cancer

Postmenopausal women with a white blood cell (WBC) count of 6.80–15.00×10⁹ cells/L are more likely to develop invasive breast cancer, colorectal cancer, endometrial cancer, and lung cancer, according to the results of a recent prospective study. The findings add to the mounting data that point to a causal link between inflammation and these types of tumors.

The study involved 40 centers and over 140,000 women aged 50 to 79 years. The authors calculated that compared to women with WBC counts in the lowest quartile (2.50–4.79×10⁹ cells/L), those in the highest quartile (6.8–15.00×10⁹ cells/L) had a hazard ratio for invasive breast cancer of 1.15 (95% CI, 1.04–1.26), for colorectal cancer of 1.19 (95% CI, 1.00–1.41), for endometrial cancer of 1.42 (95% CI, 1.12–1.79), and for lung cancer of 1.63 (95% CI, 1.35–1.97). The findings remained significant even after excluding cancers that were diagnosed during the first 2 years of follow-up and after limiting analysis to nonsmoking participants.

The researchers also found that higher WBC counts were significantly associated with a high risk of breast, lung, and overall cancer mortality.