Summary Background Aromatase inhibitors effectively prevent breast cancer recurrence and development of new contralateral tumours in postmenopausal women. We assessed the efficacy and safety of the ...aromatase inhibitor anastrozole for prevention of breast cancer in postmenopausal women who are at high risk of the disease. Methods Between Feb 2, 2003, and Jan 31, 2012, we recruited postmenopausal women aged 40–70 years from 18 countries into an international, double-blind, randomised placebo-controlled trial. To be eligible, women had to be at increased risk of breast cancer (judged on the basis of specific criteria). Eligible women were randomly assigned (1:1) by central computer allocation to receive 1 mg oral anastrozole or matching placebo every day for 5 years. Randomisation was stratified by country and was done with blocks (size six, eight, or ten). All trial personnel, participants, and clinicians were masked to treatment allocation; only the trial statistician was unmasked. The primary endpoint was histologically confirmed breast cancer (invasive cancers or non-invasive ductal carcinoma in situ). Analyses were done by intention to treat. This trial is registered, number ISRCTN31488319. Findings 1920 women were randomly assigned to receive anastrozole and 1944 to placebo. After a median follow-up of 5·0 years (IQR 3·0–7·1), 40 women in the anastrozole group (2%) and 85 in the placebo group (4%) had developed breast cancer (hazard ratio 0·47, 95% CI 0·32–0·68, p<0·0001). The predicted cumulative incidence of all breast cancers after 7 years was 5·6% in the placebo group and 2·8% in the anastrozole group. 18 deaths were reported in the anastrozole group and 17 in the placebo group, and no specific causes were more common in one group than the other (p=0·836). Interpretation Anastrozole effectively reduces incidence of breast cancer in high-risk postmenopausal women. This finding, along with the fact that most of the side-effects associated with oestrogen deprivation were not attributable to treatment, provides support for the use of anastrozole in postmenopausal women at high risk of breast cancer. Funding Cancer Research UK, the National Health and Medical Research Council Australia, Sanofi-Aventis, and AstraZeneca.
Abstract Background Traditionally axillary surgery has been used to provide staging information and until recently was thought to improve loco-regional control. However, a more minimal approach to ...the axilla is now being adopted. The aim of this study was to assess long term outcomes of patients with ‘low-risk’ breast cancers who did not undergo any axillary surgery. ‘Low-risk’ criteria were: postmenopausal, <20mm grade1 or <15mm grade2, LVI-ve, ER+ve. Methods Women with invasive breast cancer that did not undergo any axillary surgery were identified. Patients were censored when an event or death occurred or at last follow-up at breast clinic or with their General Practitioner. Results Between 05/01/1995-20/11/2006, 194 patients (199 tumours) were operated upon without axillary surgery. Median follow-up was 10.4 years. 128 patients met low-risk criteria and 71 didn’t (patient choice=42, medical fitness=29). In the ‘low risk’ cohort there were two axillary recurrences, with a cumulative incidence of 0.8% and 1.9% at 5 and 10 years respectively. DDFS was 99.2% (94.1-99.9%), and 97% (90.0-99%) at 5 and 10 years respectively and DFS was 96.6% (91.1-98.7%) and 91.2% (82.6-95.6%). OS was 90.3% (95% CI: 83.6–94.4) and 75.5% (95% CI: 65.9-82.8) at 5 and 10 years respectively. Conclusion Axillary recurrence and DDFS in this low-risk cohort is favourable. In the modern era of breast cancer management it is possible to define a group of women in whom axillary surgery can be omitted.