In a nutshell
Researchers compared therapy with anastrozole (arimidex) and letrozole (femara) to determine the effects of these drugs on the quality of life (QoL) of breast cancer patients.
Some background
In the case of hormone receptor positive (HR+) breast cancer, patients typically receive surgery, followed by adjuvant (additional) treatment with drugs that inhibit the stimulatory effect of estrogen on the growth of the cancer. One drug class used for HR+ breast cancer are the aromatase inhibitors (AIs). AIs prevent the body from producing estrogen. Two examples of AIs commonly used are anastrozole and letrozole. Letrozole is considered more effective at reducing estrogen levels in the body. However, there is some concern that letrozole might also cause more frequent or more severe side effects.
Methods & findings
Researchers compared 185 breast cancer patients who underwent a lumpectomy (removal of the tumor by surgery without removing the entire breast). Each patient was assigned to receive 12 weeks of anastrozole followed by 12 weeks of letrozole, or the same treatments in the opposite order. Patients completed QoL questionnaires before, during and after the trial.
80% of patients reported at least one side effect, the most common of which was joint pain (arthralgia). Overall, no change in QoL was noticed between the two medications. The rate of reported side effects was also the same between anastrozole and letrozole. The order of medications received did not change the rate of side effects. No preference was reported among patients for either anastrozole or letrozole.
The bottom line
In conclusion, although side effects from anastrozole and letrozole were very common, neither drug was superior when regarding patient QoL and the rate of side effects.
The fine print
This study was funded by Novartis, the pharmaceutical company that manufacturers letrozole (femara).
What’s next?
Consult with your physician regarding the possible side effects of aromatase inhibitor treatment and possible alternatives in the management of breast cancer.
Published By :
Breast Cancer Research and Treatment
Date :
Feb 01, 2011
