Study: Switching from Tamoxifen to Arimidex May Cut Risk of Recurrence

Postmenopausal breast cancer survivors who switch to Arimidex after at least two years on tamoxifen appear to have a lower risk of recurrence than those who continue on tamoxifen, according to Italian researchers.

According to results recently presented at the 2003 San Antonio Breast Cancer Symposium, switching to Arimidex® after at least 2 years of tamoxifen reduces the risk of cancer recurrences compared to continued tamoxifen in postmenopausal women with estrogen-receptor positive breast cancer.

The Italian researchers conducted a clinical trial involving more than 400 postmenopausal women with ER-positive breast cancer to compare Arimidex -- a member of a new class of drugs known as aromatase agents -- to tamoxifen in patients already treated with tamoxifen.

The participants either received either continued tamoxifen for up to 5 years, or Arimidex for a comparable period of time.

This trial included over 400 postmenopausal women with ER-positive breast cancer, who had already been treated with at least 2 years of tamoxifen. Patients then received either continued tamoxifen for up to 5 years, or Arimidex® for a comparable duration of time. matched time.

After two to three years of follow-up, researchers found that recurrence rates were reduced by more than 60 percent in the group of patients who switched to Arimidex compared to those who continued on tamoxifen.

The researchers concluded that postmenopausal women with ER-positive breast cancer who switch to Arimidex after at least 2 years of tamoxifen have a significantly reduced rate of cancer recurrence, but cautioned that larger trials are necessary to confirm this finding.

Patients who are being treated with tamoxifen may wish to speak with their physician about the risks and benefits of switching.

Other Sources: San Antonio Breast Cancer Symposium