Last reviewed: July 2006
For general information about Cancerbackup's Discussion topics please see the introductory page.
This discussion topic explores the use of hormonal therapies in early breast cancer. It aims to discuss and summarise the issues and is written for health professionals. It may also be of interest to patients. Information for patients can be found in the breast cancer section.
Since the latest results of the ATAC (Arimidex, Tamoxifen, Alone or in Combination) trial were announced in December 2004, questions have been asked by patients, patient families and clinicians about the best hormonal therapy treatment for oestrogen-positive early-stage breast cancer.
Premenopausal women
For women who are premenopausal, tamoxifen remains the treatment of choice. Tamoxifen is a SERM (Selective Estrogen Receptor Modulator) with both oestrogenic and anti-oestrogenic properties. Goserelin (Zoladex), a gonadorelin (LHRH) analogue which works on the pituitary gland, may also be used. This drug causes a temporary chemical menopause which is reversed once the drug is stopped.
Postmenopausal women
For post menopausal women, tamoxifen has also been the drug of choice. Following the ATAC data presented in 2002, it was felt that the standard treatment should continue to be tamoxifen for five years. However, for women at high risk of thromboembolic disorders or endometrial abnormalities, or those who could not tolerate tamoxifen, anastrozole could be used instead.
Current evidence suggests that using aromatase inhibitors may be preferable to using tamoxifen. However, there is still much uncertainty and trials have investigated different aromatase inhibitors in different ways. These have been
- using aromatase inhibitors directly after surgery
- switching to an aromatase inhibitor after two to three years of tamoxifen or
- using an aromatase inhibitor after five years of tamoxifen.
This paper summarises the current state of knowledge and the criteria for treatment selection.