Tamoxifen Exemestane Adjuvant Multinational (TEAM) study reports

Following breast cancer treatment, women are given adjuvant therapy with either tamoxifen or an aromotase inhibitor such as exemestane, or sequential treatment of tamoxifen followed by emexestane. The results of the TEAM study—published in The Lancet—show that while sequential treatment offers a similar disease-free survival rate to emexestane alone, the side effects of the regimens are different. Thus particular groups of patients should be identified to benefit from a particular regimen. The article is by Prof Cornelis J H van de Velde, Leiden University Medical Centre, Netherlands, and colleagues.

Most local guidelines across high-income countries recommend that aromatase inhibitors should be included in adjuvant treatment for postmenopausal patients with hormone receptor-positive breast cancer, but defer the decision for either upfront or sequential treatment to the individual doctor. But the current picture is mixed depending on the location.

In TEAM, postmenopausal women (median age 64 years, range 35–96) with hormone-receptor-positive breast cancer were randomly assigned in a 1:1 ratio to open-label exemestane alone (25 mg once a day, orally—4898 patients analysed) or following tamoxifen (20 mg once a day, orally—4868 patients analysed) for 5 years. 85% patients in the sequential group and 86% in the exemestane alone group were disease free at 5 years.

In the safety analysis, sequential treatment was associated with a higher incidence of gynaecological symptoms (20% vs 11%), venous thrombosis (2% vs 1%), and endometrial abnormalities/thickening (4% vs <1%) than was exemestane alone. Musculoskeletal adverse events (50% vs 44%), high blood pressure (6% vs 5%), and abnormal blood fats (5% vs 3%) were reported more frequently with exemestane alone.

The authors conclude: "Treatment regimens of exemestane alone or after tamoxifen might be judged to be appropriate options for postmenopausal women with hormone-receptor-positive early breast cancer...Because of the differences in profiles of the adverse events between exemestane monotherapy and sequential treatment (tamoxifen followed by exemestane), consideration of the safety of these treatment strategies might play an important part in treatment decisions. Translational research within TEAM and other trials of aromastase inhibitors might identify specific populations of patients who could benefit most from a particular strategy."


Source: The Lancet

Article: Abstract