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.