Postmenopausal woman with early breast cancer who have completed standard adjuvant Tamoxifen therapy now have the option of further treatment following the extension to the licence of letrozole (Femara).

After surgery, standard hormonal therapy for postmenopausal women with early breast cancer is Tamoxifen, usually for five years. After this, there is no evidence of further benefit and treatment is usually stopped because of increased risk of endometrial cancer, pulmonary embolism and stroke. About a third of patients who are oestrogen-receptor positive experience recurrence and over half of these occur after treatment is stopped.

Now these women can switch to the aromatase inhibitor letrozole, which can be taken for up to three and has been shown to reduce recurrence.

The trial supporting this (the MA-17 study) showed that letrozole after standard Tamoxifen therapy reduces recurrence by 42 per cent (P=0.00004) and reduces distant metastases by 39 per cent (P=0.003) (PJ, 18 October 2003). An increased risk of osteoporosis was recorded , although with no higher risk of fractures than with placebo. Letrozole costs £83.16 per patient per month.

Letrozole is also licensed for the first line treatment of advanced breast cancer in postmenopausal women who are oestrogen receptor positive or unknown, in women with advanced breast cancer with disease progression after anti-oestrogen therapy, and as preoperative therapy.