Estradiol concentrations linked to breast cancer recurrence

The risk for recurrence in women diagnosed and treated for early-stage breast cancer may be linked to higher concentrations of serum estrogen, according to data published in Cancer Epidemiology, Biomarkers and Prevention.

To determine the relationship between recurrence-free survival and levels of estriol, testosterone and sex hormone binding globulin, researchers from the University of California in San Diego and other institutions, examined a case-control group of the 3,088 women enrolled in the Women’s Healthy Eating and Living Study, a randomized diet trial. Researchers followed these women for more than seven years after their diagnosis.

In the current study, 153 of the 3,088 WHEL participants whose cancer recurred were matched with 153 participants whose cancer did not return. Researchers found that concentrations of total estradiol, bioavailable estradiol and free estradiol were associated with recurrence risk in these 153 pairs of perimenopausal and postmenopausal women. The average estradiol concentration in women with a recurrence was twice that of women who did not have a recurrence (22.7 vs. 10.8 pg/mL; P=.05), according to the study.

Researchers did not find a link between risk for recurrence and concentrations of testosterone and sex hormone binding globulin. – by Stacey L. Adams

Cancer Epidemiol Biomarkers Prev. 2008;doi:10.1158/1055-9965.EPI-07-0761.

This article is very interesting and it is somewhat in line with some of the research we are doing here at the Medical College of Georgia Cancer Center in terms of looking at the correlation between hot flashes and subsequent recurrent breast cancer.

At the moment, I am not sure how to incorporate this data into clinical practice because it’s very interesting and provocative; however, the authors acknowledge in the article itself that there were limitations in the study. Some of these patients were perimenopausal, as opposed to postmenopausal, and estrogen levels can vary widely in these patients. The researchers also only drew the hormone levels at one point in time as opposed to serial examinations. So the fact that they happened to find an association is very interesting and requires more study. However, that’s as far as I would take it; I don’t believe physicians should be following reproductive hormone levels for this specific reason; ie, to assess for a particular patient’s breast cancer recurrence risk. However, one can use measurement of these levels to guide what form of hormonal therapy should be used to adjuvantly treat patients with hormone-sensitive breast cancer.

– Thomas Samuel, MD

Director, Medical College of Georgia Cancer Center Clinical Breast Cancer Program, Augusta, Ga.