Transvaginal Sonographic and Hysteroscopic Findings in Postmenopausal Women Receiving Tamoxifen

The effect of tamoxifen on the endometrium was assessed by transvaginal color Doppler sonography, hyteroscopy, and histology in 90 postmenopausal women, of whom 71 were asymptomatic and 19 had vaginal bleeding. All were treated with tamoxifen 20 to 30 mg/day for breast cancer for at least 1 year and all underwent transvaginal color Doppler sonography. Women with endometrial thickness greater than 5 mm and with vaginal bleeding were advised to undergo hysteroscopy and endometrial biopsy if necessary. In asymptomatic women with endometrial thickness of 5 mm or less, hysteroscopy was recommended if irregular endometrial echotexture was observed. Nine (12.7%) asymptomatic patients and 1 (5.3%) with vaginal bleeding had an endometrial width of 5 mm or less (p = 0.6, NS). Those with vaginal bleeding receiving tamoxifen had a significantly thicker endometrium than asymptomatic women (16.1 ± 7.7 vs 11.1 ± 5.7 mm, p = 0.003). A typical sonographic endometrial pattern with small hypoechoic cystic areas was reported in 83% of patients. In the asymptomatic group, 25 polyps, and 7 atrophic and 13 thickened endometria were observed at hysteroscopy. Two endometrial cancers, 11 polyps, and 1 atrophic and 4 thickened endometria were present in women with vaginal bleeding. Hysteroscopy did not always allow endometrial biopsy even if endometrial thickness with or without an irregular surface was observed. No statistical differences were revealed in the two tamoxifen groups for the mean pulsatility and resistance indexes of the uterine and endometrial arteries, which were otherwise significantly lower compared with normal postmenopausal values. Women receiving tamoxifen, especially asymptomatic women, should be closely monitored by transvaginal color Doppler ultrasonography and hysteroscopy to detect endometrial pathologies.