Long-term transvaginal ultrasonographic endometrial follow-up in postmenopausal breast cancer patients with tamoxifen treatment.

OBJECTIVE: The aim of this study was to evaluate changes in transvaginal ultrasonographic endometrial thickness with increased duration of tamoxifen treatment in postmenopausal breast cancer patients.
MATERIAL AND METHODS: In this prospective study we evaluated the changes (mean +/- SD) of endometrial thickness measured by transvaginal ultrasonography in 181 postmenopausal breast cancer patients, according to the duration of tamoxifen treatment. According to our protocol, the ultrasonographic evaluations were performed every 6 months for the first 2 years of the follow-up and every 12 months thereafter. Two such subsequent ultrasonographic evaluations were performed in 181 patients following 35.1 +/- 41.7 months of tamoxifen treatment, three studies in 127 patients following 44.7 +/- 47.98 months of treatment, four studies in 75 following 54.2 +/- 61.7 months of treatment, five studies in 51 patients following 65.3 +/- 74.4 months of treatment, and six studies in 27 patients following 79.5 +/- 98.8 months of treatment.
RESULTS: The measured endometrial thickness detected varied from 8.84 +/- 4.66 to 10.61 +/- 12.35 mm. There were no significant changes in mean +/- SD of endometrial thickness following various durations of tamoxifen treatment.
CONCLUSIONS: Extension of duration of tamoxifen treatment in postmenopausal breast cancer patients up to 79.48 +/- 98.79 consecutive months does not cause a significant increase in transvaginal ultrasonographic endometrial thickness. Copyright 1999 Academic Press.