Survival improved by letrozole after tamoxifen
Treatment with the aromatase inhibitor letrozole (Femara), after completion of standard tamoxifen therapy, significantly improves disease-free survival early results of a study have shown.
The international trial studied 5,187 postmenopausal women with primary
breast cancer who had completed around five years of adjuvant tamoxifen
therapy. The women were randomly assigned to receive letrozole 2.5mg,
or placebo, daily for five years.
Interim results at 2.4 years showed a 43 per cent reduction in the risk
of breast cancer recurrence and a 46 per cent relative reduction in disease
spreading from one breast to the other. There was a substantial reduction
in the rate of distant metastases in the letrozole group compared with
the placebo group, and the rate of death due to breast cancer was almost
halved. Since these results were so promising, the independent data and
safety monitoring committee recommended termination of the trial and
consideration of letrozole therapy for women in the placebo group.
No significant difference in toxic effects was found between the two
groups. However, the authors note that aromatase inhibitors decrease
oestrogen levels and may also reduce bone mineral density and cause hypercholesterolaemia.
There were new diagnoses of osteoporosis in 5.8 per cent of the letrozole
group and 4.5 per cent the placebo group (New England Journal of Medicine 2003;349:19). |
