CHICAGOThe role of endocrine therapy in breast cancer is still
evolving, with about half a dozen agents contending as players in the
metastatic, adjuvant, and chemoprevention settings. At the Lynn Sage Breast
Cancer Conference, William J. Gradishar, MD, summarized recent clinical trials
and put the current agents into a clinical context for oncologists.
Dr. Gradishar is director of Breast Medical Oncology at the Robert H. Lurie
Comprehensive Cancer Center and associate professor of medicine at Northwestern
Clinical trials have shown a wide range of response to various endocrine
therapies, largely because of heterogeneity and variability in subjects and
trial design. Generally, however, about one third of patients will respond to
endocrine therapies, he said.
Candidates for Therapy
Dr. Gradishar summed up the general suitability of patients for endocrine
therapies as "patients who are hormone-receptor (HR)-positive, have a long
disease-free interval between their initial diagnosis of breast cancer and
metastatic disease, and generally have nonvisceral disease. Although visceral
disease will also respond, it is probably more suitable for chemotherapy
The idea that premenopausal patients do not respond to endocrine therapy is
probably a misconception, he said, "but the frequency of HR-positive
disease is clearly greater in older patients."
Patients who respond to one endocrine therapy have an increased likelihood
of responding to subsequent endocrine maneuvers. "While response rates
generally diminish with each succeeding therapy, there are patients who can go
on to second-, third-, fourth-, and even fifth-line therapy. The fundamental
question we grapple with as newer agents go forward is the sequence with which
to use these agents," he said.