Immunity Boosters Linked to Leukemia
Drugs That Boost Immunity During Cancer Chemo May Carry Leukemia Risk
Feb. 6, 2007 -- There may be a small leukemia risk from drugs used to boost
immunity during cancer chemotherapy, a new study suggests.
Cancer chemotherapy often decreases the number of the body's
infection-fighting white blood cells. Drugs known as growth factors boost the
growth of new white blood cells during chemo.
But the drugs, G-CSF (such as Neupogen) and GM-CSF (such as Leukine), may
themselves cause rare cases of leukemia, find Columbia University researcher
Dawn Hershman, MD, and colleagues.
Hershman's team looked at data collected on more than 5,500 women -- aged 65
and older -- treated with chemotherapy for breast cancer.
Chemotherapy itself can cause leukemia. Indeed, 1.04% of the women who did
not receive growth factors developed leukemia. But 1.77% of the women treated
with G-CSF or GM-CSF developed leukemia. Statistically, the drugs seemed to
double a woman's leukemia risk -- although that risk remained quite small.
"The benefits of G-CSF may still outweigh the risks," Hershman and
colleagues conclude. "However, G-CSF use should not be assumed to be risk
The study appears in the Feb. 7 issue of the Journal of the National
Cancer Institute. An editorial by Ivo P. Touw, PhD, and Marijke Bontenbal
of Erasmus University in Rotterdam, Netherlands, accompanies the study.
Touw and Bontenbal note that even if growth factors are linked to leukemia,
the drugs' risks are much smaller than their benefits for cancer chemotherapy