Significance of secondary ultrasonographic endometrial thickening in postmenopausal tamoxifen-treated women

BACKGROUND: Ultrasonography has a limited value in endometrial assessment for identification of endometrial pathologies in postmenopausal tamoxifen-treated patients. METHODS: We compared the rate of endometrial pathologies and the mean +/- SD of endometrial thickness diagnosed after the first and second transvaginal ultrasonographic studies performed on 55 postmenopausal tamoxifen-treated patients with secondary endometrial thickening (Group I). This rate was also compared with 46 similar patients without secondary thickening (Group II). We also compared the mean +/- SD of endometrial thickness detected in various ultrasonographic studies, as well as various clinical features. RESULTS: A significantly higher rate of endometrial pathologies, including two cases of endometrial cancer identified in gynecologically asymptomatic patients (3.6%), was diagnosed in Group I after the second study compared with the first study (52.7% and 9.1%, respectively; P = 0.001) and compared with those diagnosed after the second study in Group II (30.4%; P = 0.03). There was a significant increase (74.7 +/- 115%) in endometrial thickness after the second study compared with the first study performed on Group I (10.7 +/- 5.53 mm and 16.59 +/- 5.53 mm, respectively; P = 0.0001) and a significant difference in endometrial thickness demonstrated in the second study performed on Groups I and II (16.59 +/- 5.53 mm and 11.4 +/- 3.91 mm, respectively; P = 0.001).There were no significant differences in the time elapsed since the diagnosis of breast carcinoma and from the beginning of tamoxifen treatment to the performance of the first ultrasonographic study as well as the time elapsed between the first and second studies performed. CONCLUSIONS: A significant increase (> 50%) in secondary endometrial thickening, measured ultrasonographically, in postmenopausal tamoxifen-treated patients, is associated with a high rate of endometrial pathologies, including endometrial cancer.