Study: Disparities exist worldwide in early breast cancer treatment
Lead author C. J. H. van de Velde, PhD, from the Leiden University Medical Center in the Netherlands, and colleagues utilized information from their tamoxifen and Exemestane Adjuvant Multinational (TEAM) trial, an international randomized trial evaluating the efficacy and safety of exemestane, alone or following tamoxifen.
"Because we had recruited a large number of patients, we decided that this also provided us with an invaluable opportunity to examine how different countries treat postmenopausal women with early breast cancer,” explained van de Velde.
From 2001-2006, 9,779 patients with an average age of 64 were recruited from 566 study sites in Belgium (414 women), France (1,230), Germany (1,471), Greece (207), Japan (184), the Netherlands (2,753), the U.K. and Ireland (1,275) and the U.S. (2,232). Patient characteristics, including date of birth, menopausal status, medical history, height, weight and tumor characteristics such as primary disease site were recorded. Eligibility criteria had minor differences between the countries, which reflected national guidelines and practice variations regarding adjuvant endocrine therapy, said the authors.
Of the women recruited, 58.4 percent had T1 tumors and 47.3 percent were axillary node positive. Independent factors for type of breast surgery were country, age, tumor status and calendar year of surgery, they wrote.
The researchers found that following breast-conserving surgery, France and Belgium were the only countries to report 100 percent treatment rates, despite international guidelines that radiotherapy should be part of breast-conserving therapy. The U.K. and Ireland reported conducting this practice 13 percent of the time and the U.S. and Japan, 14 percent. Radiotherapy following mastectomy was administered at an average rate of 39 percent across the countries and women receiving axillary lymph node dissection consisted of 82 percent of the patient-population.
In addition, the authors said that women with T1 tumors were more likely to receive breast-conserving surgery. However, despite the fact that T1 tumor rates were similar in the U.S. and France, 89 percent of T1 tumors were treated with breast-conserving surgery in France compared to 55 percent in the U.S.
Moreover, they found that women with T2 tumors were more likely to receive a mastectomy than breast-conserving surgery, ranging from 42 percent in France to 69 percent in the U.S. The overall mastectomy rate for all tumors was 44 percent, with the lowest rate at 19 percent in France and the highest rate in Greece, at 56 percent.
“Our study showed that despite international consensus guidelines, there are wide global variations in the way postmenopausal women are treated for early breast cancer,” said van de Velde and colleagues. "We believe that there should be further efforts to optimize locoregional treatment for breast cancer worldwide."