927 Endometrial polyps are localized overgrowths of en- dometrial tissue that is composed of a variable amount of glands, stroma, and blood vessels that is covered by ep- ithelium. 1 They can be seen by hysteroscopy in women with abnormal uterine bleeding, but even incidentally di- agnosed in asymptomatic women during a transvaginal sonography that is performed for other indications. The introduction of saline infusion sonography into clinical practice has led to the diagnosis of an increasing number of polyps. The prevalence in women with abnormal uter- ine bleeding varies widely in the literature, ranging around 10% to 30% in relation to hormonal status. 2-4 It has been calculated that, as a consistent proportion of en- dometrial polyps does not produce symptoms, the preva- lence in the general female population can be estimated at approximately 24% to 25%. 5-8 The clinician has to face the issue of how to treat endometrial polyps because they are being diagnosed in growing numbers even in asymp- tomatic women and because their malignant potential is not understood fully yet. Polyps are believed commonly to be a risk factor for endometrial cancer because hyper- plastic and neoplastic lesions can be found in their con- text. Unfortunately, most of the published reports are based on specimens obtained at curettage, which fails to remove many focally growing lesions in the endometrial cavity and often extracts only scarce fragments. 4,9,10 Hys- teroscopic polypectomy is the treatment of choice be- cause it ensures the removal of the entire lesion and not the adjacent endometrium. However, hysteroscopy is ex- pensive and may be associated with mild or severe mor- bidity and even death 11 so that it is not clear whether to offer hysteroscopic polypectomy to any patient, even if the patient is asymptomatic. The objective of this study was to estimate the prevalence of hyperplasia and cancer in a large number of endometrial polyps that were re- moved entirely by operative hysteroscopy and to evaluate whether clinical parameters may predict the final histopathologic feature of the polyp. Material and methods A surgical database was used to identify all patients who consecutively underwent hysteroscopic removal of en- dometrial polyps over a 48-month period from January 1998 to December 2001. Women were scheduled for op- erative hysteroscopy after a diagnosis of endometrial polyp was made either by hysteroscopy or by transvaginal From the Departments of Obstetrics and Gynecology a and Pathology b and Rizzoli Research Institute, c University of Bologna. Received for publication June 28, 2002; revised August 14, 2002; ac- cepted December 30, 2002. Reprint requests: Luca Savelli, MD, Department of Obstetrics and Gyne- cology, University of Bologna Via Massarenti, 13, 40138 Bologna, Italy. E-mail: lucasavelli@rocketmail.com © 2003, Mosby, Inc. All rights reserved. 0002-9378/2003 $30.00 + 0 doi:10.1067/mob.2003.247 Histopathologic features and risk factors for benignity, hyperplasia, and cancer in endometrial polyps Luca Savelli, MD, a Pierandrea De Iaco, MD, a Donatella Santini, MD, b Federica Rosati, MD, a Tullio Ghi, MD, a Elettra Pignotti, BSc, c and Luciano Bovicelli, MD a Bologna, Italy OBJECTIVE: The purpose of this study was to determine the rate of benign, hyperplastic, and malignant en- dometrial polyps and whether clinical data can predict histopathologic outcome. STUDY DESIGN: Five hundred nine patients with endometrial polyps who consecutively underwent hystero- scopic removal of endometrial polyps over 48 months were identified from our gynecologic oncology surgical database. Medical reports provided clinical data. Statistical analysis was performed. RESULTS: Histologically, 358 polyps (70.3%) were benign; 131 polyps (25.7%) had simple or complex en- dometrial hyperplasia, 16 polyps (3.1%) had hyperplasia with atypia, and 4 polyps (0.8%) were cancerous. Polyps were divided into group A and group B, according to the risk of malignancy (group A, benign; group B, atypical hyperplastic and cancerous). Age, menopause status, and hypertension were associated signifi- cantly with group B. CONCLUSION: Endometrial polyps rarely become malignant, but hyperplastic changes are more common. Age, menopause status, and hypertension may increase the risk of premalignant and malignant polyps.To achieve complete removal of the polyp and a reliable histologic analysis, operative hysteroscopy should be offered to symptomatic patients or to patients with risk factors. (Am J Obstet Gynecol 2003;188:927-31.) Key words: Endometrial polyps, hyperplasia, endometrial cancer, risk factors, hysteroscopy