In a nutshell
This article looked at the effects of endocrine therapy on hormonal changes during cancer treatment.
Some background
Hormone therapy to treat breast cancer is called endocrine therapy. This treatment is used in hormone receptor positive (HR+) early breast cancer. It causes changes to hormone signalling which can lead to early menopause in women. An increased risk of bone loss is also a side-effect to these treatments. Zoledronic acid is an agent used with endocrine therapy for breast cancer that improves bone mineral density (indicates bone strength). Endocrine therapy plus zoledronic acid has unknown side-effects however, particularly on hormone levels.
Methods & findings
The aim of this study was to evaluate the hormone level changes in premenopausal women following endocrine therapy and zoledronic acid for HR+ early breast cancer. An endocrine hormone called estradiol-RIA (E2) was monitored for changes.
70 premenopausal women with HR+ early breast cancer were involved in the study. 34 of these women received endocrine therapy plus zoledronic acid while 36 of the women received endocrine therapy plus placebo (substance with no therapeutic effect) for 24 months at 3 month intervals. They were followed up over 3 years.
There were slight changes in blood hormone levels, though not significant. This tells us that using zoledronic acid alongside endocrine therapy is well tolerated in premenopausal women and does not affect hormone levels.
The bottom line
The authors concluded zoledronic acid can be safely used alongside endocrine therapy in HR+ breast cancer.
The fine print
As this was a 2 year study, hormone level changes have not been observed over a long-term period.
Published By :
Breast Cancer Research and Treatment
Date :
Feb 12, 2014
