Abstract
Objectives
This study prospectively assessed the effects of exemestane and tamoxifen on the endometrium
in patients receiving adjuvant treatment for postmenopausal hormone receptor-positive
breast cancer within the Tamoxifen Exemestane Adjuvant Multicenter (TEAM) trial.
Methods
Patients were randomized to receive tamoxifen or exemestane. In a prespecified trial
subprotocol, patients underwent transvaginal ultrasound to assess endometrial thickness
at baseline and during a 1- to 3-year treatment period.
Results
Among 143 evaluable patients, there were no cases of endometrial thickness >10 mm with exemestane, vs. 11 cases with tamoxifen (p<0.0003). There was a significant difference between the treatment groups regarding
time to endometrial thickness >10 mm, in favour of exemestane (p<0.0001). Time to endometrial thickness >5 mm was significantly longer for exemestane than for tamoxifen (p<0.0001). Median time to endometrial thickness >5 mm or censoring was 583 days in the exemestane group versus 315 days in the tamoxifen group. There were also significantly fewer incidences of endometrial
thickness >5 mm at month 6 and month 12 with exemestane compared to tamoxifen (tamoxifen: 6% and
2%; exemestane: 29% and 39%, respectively). After 12 months, mean increases in endometrial thickness from baseline were 2.64 mm and 6.0 mm in the exemestane and tamoxifen groups, respectively (p<0.0006). Moreover, 17 histologically confirmed endometrial changes were observed in
the tamoxifen group, vs. one in the exemestane group.
Conclusions
Exemestane was associated with significantly less endometrial thickening than tamoxifen
during adjuvant endocrine therapy for postmenopausal hormone receptor-positive breast
cancer.
Keywords
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Article info
Publication history
Received:
February 10,
2010
Identification
Copyright
© 2010 Elsevier Inc. Published by Elsevier Inc. All rights reserved.
