BUFFALO, NYBreast cancer offers a paradigm for cancer
prevention issues. It has been shown that lower exposure to estrogen
results in a lower risk of breast cancer. However, a decrease in
overall estrogen may pose health risks for women such as increased
risk for heart disease. Thus, patients and physicians must evaluate
all options available, said Richard M. Elledge, MD, medical director
of the Breast Care Center at Baylor College of Medicine-The Methodist
Selective estrogen receptor modulators (SERMs) offer a
potential method to interrupt the transformation of normal breast
tissue into cancer. But the currently available SERMs such as
tamoxifen [Nolvadex] do not meet all of our needs. There is still
work to be done to create the ideal preventive
agent, Dr. Elledge said at the New Horizons in Cancer
Prevention Symposium, hosted by Roswell Park Cancer Institute.
An ideal SERM would be antiestrogenic in both the breast and uterus,
maintain bone density, decrease cholesterol levels, be estrogenic in
the brain, have no effect on clotting, and sustain this profile over time.
The SERM currently approved for prevention, tamoxifen, only
meets part of the criteria for an ideal SERM. Its negative effect in
the uterus and its inability to remain antiestrogenic after long-term
use make it useful for now, but it is not the answer we need,
Dr. Elledge said.
Newer SERMs, such as raloxifene (Evista), may be closer to the ideal
profile, but only long-term clinical trials such as STAR (Study of
Tamoxifen and Raloxifene) will answer this question, he said. There
is also a real need for validated biomarkers to better identify
effective agents in a faster period of time, he said.
The possibility of side effects limits the general use of
SERMs. We need better methods of identifying patients who need to
consider the use of preventive SERM therapy; we need to deal with the
other obstacles to the widespread use of these drugs; and we need to
find a way to get these answers faster so we can help women make the
best choice for their care, Dr. Elledge said.