Originally posted by Kathi Leahy. . .
A Blood Test Predicts Survival in Metastatic Breast Cancer
In a prospective, multicenter, double-blind study, investigators
examined whether levels of circulating tumor cells can predict
survival in women with metastatic breast cancer. Using a new
technology, they counted tumor cells in whole blood samples from 177
patients with measurable metastatic breast cancer who were about to
begin new systemic therapy, as well as in samples from women with no
illness or with benign breast conditions. (A laboratory with
commercial interest in the technology sponsored the study.)
At baseline, circulating tumor cells, re****ted per 7.5 mL of whole
blood, were rare in healthy women and in those with benign breast
conditions (mean in each group, 0.1). Only 1% of these women had two
or three cells, and none had more. In contrast, almost two thirds of
patients with metastatic breast cancer had two or more tumor cells.
Patients with five or more circulating tumor cells at baseline (49%)
had significantly shorter median progression-free and overall survival
(approximately 3 and 10 months, respectively) than patients with
fewer
cells (approximately 7 and >18 months, respectively). Similarly,
evaluable patients with five or more cells at the first follow-up
visit (at a mean 4.5 weeks after baseline) had significantly shorter
median progression-free and overall survival (approximately 2 and 8
months) than those with fewer cells (approximately 7 and >18 months).
Levels of circulating tumor cells predicted survival better than
traditional parameters, including estrogen-receptor, progesterone-
receptor, and HER2/neu status.
Comment: These convincing findings demonstrate that in women with
metastatic breast cancer, levels of circulating tumor cells -- at
initiation of new therapy and at follow-up -- indeed predict
survival. The short survival times in patients with elevated tumor-
cell levels at follow-up underscore the need for alternative
therapeutic strategies. The authors point out that their findings do
not suggest that measuring circulating tumor cell levels is useful in
screening for primary or metastatic breast tumors.
- Andrew M. Kaunitz, MD
Published in Journal Watch Women's Health October 19, 2004
Source
Cristofanilli M et al. Circulating tumor cells, disease progression,
and survival in metastatic breast cancer. N Engl J Med 2004 Aug 19;
351:781-91.
http://womens-health.jwatch.org/cgi/content/full/2004/1019/1?q=etoc
|
