Computer Program Can Help You Decide Which Hormonal Therapy to Take
Reviewed study: "Computer Program Can Help You Decide Which Hormonal Therapy to Take" by H.J. Burstein et al., American Society of Clinical Oncology Annual Meeting, May 2005, Abstract #529
Background and importance of the study: If you're a post-menopausal woman with hormone-receptor-positive breast cancer, you have several choices for hormonal therapy. You can:
- take tamoxifen for five years,
- take an aromatase inhibitor for five years,
- take tamoxifen for two to three years and then take an aromatase inhibitor for another two to three years, or
- take tamoxifen for five years and then take an aromatase inhibitor for two to three years.
Research has shown that women who took tamoxifen for two and a half years and then switched to an aromatase inhibitor lived longer without the cancer coming back (disease-free survival) than women who stayed on tamoxifen for the full five years.
Your hormone receptor status actually involves two hormones: estrogen and progesterone. So far, though, we haven't heard much about how estrogen receptor status and progesterone receptor status can help a woman and her doctor figure out what the best hormonal therapy treatment would be.
Study Design: In this study, the researchers looked at women whose cancers were either:
- ER+/PR+ (estrogen-receptor-positive and progesterone-receptor-positive) or
- ER+/PR– (estrogen-receptor-positive and progesterone-receptor-negative).
The researchers used the results of a number of randomized clinical studies that had already been conducted. They included information on
- the type of breast cancer (ER+/PR– or ER+/PR+),
- the type of treatment (taking an aromatase inhibitor for five years, taking tamoxifen for five years, or taking tamoxifen for two years and then switching to an aromatase inhibitor for another three years), and
- how long women lived without the cancer coming back.
For example, did women with ER+/PR– cancers do better if they took tamoxifen for five years, or if they switched from tamoxifen to an aromatase inhibitor after two years? How about women with ER+/PR+ cancers? The researchers wrote a computer program to pull all of these findings together and create a model that can predict the best treatment for a woman, depending on her hormone receptor profile.
Results: The computer model suggested that your hormone receptor status can make a difference when you are considering different treatments:
- For women with ER+/PR– breast cancer, taking an aromatase inhibitor for five years was the best treatment.
- For women with ER+/PR+ breast cancer, switching to an aromatase inhibitor after two years of tamoxifen was the best treatment.