White blood cell count linked to cancer mortality

NEW YORK (Reuters Health) – The results of a new study show
that individuals with high white blood cell (WBC) counts appear
to have a higher risk of death from all types of cancer, a
multicenter team reports in the Archives of Internal Medicine.

Dr. Anoop Shankar of the National University of Singapore
and colleagues conducted a study of 3,189 subjects in the Blue
Mountains region, west of Sydney, Australia. The subjects were
between 49 and 84 years old and free of cancer at study
enrollment between January 1992 and December 1994. Vital status
was assessed for all subjects as of December 31, 2001.

“Higher WBC count was found to be associated with all
cancer mortality,” the investigators report. Subjects with the
highest WBC counts had a 73% higher risk of cancer death
compared with those with the lowest counts. An increase in WBCs
can indicate a variety of problems including infection, an
allergic reaction or leukemia.

The association between high WBC count and cancer was lower
among aspirin users, suggesting a possible protective effect.

Shankar and colleagues surmise that WBC is a “reasonable
but nonspecific marker” for inflammation.

Other conditions, such as cardiovascular disease, may
influence the association, but the researchers believe that
“results of this study support the hypothesis of an association
between high WBC count and cancer mortality.”

They suggest that “local inflammatory processes that have
long been known to be associated with tumor progression may be
reflected in the systemic inflammatory marker of higher WBC
count.”

SOURCE: Archives of Internal Medicine, January 23, 2006.