Histologic Features and Differential Diagnosis of Endometrial Polyps; An Update and Review

Abstract

IntroductionAmong the endometrial lesions, endometrial polyps (EPs) are commonly seen in the premenopausal and postmenpuasal age group and are found in 25% of endometrial specimens performed for abnormal uterine bleeding (1). EPs are generally considered as local hyperplasitic lesions of endometrial stroma which covered by epithelium. These lesions are seen single or multiple, sessile or pedunculated and the size range differs from millimetres to centimetres. In 10% of cases they mimic endocervical polyp due to prolapsus from external os (2,3). In a case of sufficient clinical, hysteroscopic and imaging information, the histologic diagnosis is usually straightforward. From clinical and prognostic standpoint, it should be emphasized that rarely these lesion may harbour premalignant and malignant lesions particularly in older age group. Therefore careful histologic examination for rule out of raised malignant lesions should be considered. In the other hand in rare cases these lesions may show metastatic involvement particularly from lobular breast carcinoma. Prevalence of these lesions in association with clinical presentation and histologic features will be presented and differential diagnosis with special emphasis on rule out of malignant lesions will be discussed. PrevalenceIn the 2402 office hysteroscopy performed on women with mean age of 39.4 years old for several indications, the prevalence of EP was 27.2% (4). Based on used diagnostic method and study group the mentioned rate varies between 6% to 32% and this rate increases with age (5-7). In another large study carried out on 686 Danish women in range of 20-79 years of old who accepted to be examined by both transvaginal sonography and saline contrast sonohysterography, the prevalence of EP was 7.8% (5). In this study the EPs were rare (0.9%) between young women and in women older than 30 years the prevalence was 9.2%. EPs are rarely found in OCP user whereas in the women who were on hormone replacement therapy the prevalence was much higher (2.1% vs. 25%) (5). Respect to hormones as an etiologic factor, high frequency of endometrial hyperplasia was found in the non-polyploid region of endometrium in premenopausal and postmenopausal women (8). Clinical PresentationThe usual clinical presentations of EPs may include menorrhagia, intermenstrual bleeding, postmenopausal bleeding and infertility. However the majority of patients may be asymptomatic and the prevalence could be similar in symptomatic and asymptomatic women (5). These findings indicates that there is no consistent relationship between abnormal uterine bleeding and existence of EPs and why hysteroscopic resection of EPs does not always result in relief of symptoms (9). A pathologist should be alert that in the most cases of protruded EPs, the usual clinical diagnosis will be endocervical polyp by the gynaecologist. Regard to tamoxifen, EPs are the most common pathology that could be seen in these patients. In these patients the prevalence of AbstractAmong the endometrial lesions, endometrial poly...