Variations in locoregional therapy in postmenopausal patients with early breast cancer treated in different countries

Background: The Tamoxifen and Exemestane Adjuvant Multinational (TEAM) trial is an international randomized trial evaluating the efficacy and safety of exemestane, or following tamoxifen. The large number of patients already recruited offered the opportunity to explore locoregional treatment practices between countries. Methods: Patients were enrolled in Belgium, France, Germany, Greece, Ireland, Japan, the Netherlands, the UK and the USA. The core protocol had minor differences in eligibility criteria between countries, reflecting variations in national guidelines and practice regarding adjuvant endocrine therapy. Results: Between 2001 and 2006, 9779 patients of mean(s.d.) age 64(9) years were randomized. Some 58.4 per cent had T1 tumours (range between countries 36.8-75.9 per cent; P < 0.001) and 47.3 per cent were axillary node positive (range 25.9-84.6 per cent; P < 0.001). Independent factors for type of breast surgery were country, age, tumour status and calendar year of surgery. After breast-conserving surgery, radiotherapy was given to 93.2 per cent of patients, 86.0 per cent in the USA and 100 per cent in France. Axillary lymph node dissection was performed in 82.0 (range 74.6-99.1) per cent. Conclusion: Despite international consensus guidelines, wide global variations were observed in treatment practices of early breast cancer. There should be further efforts to optimize locoregional treatment for breast cancer worldwide.