How often are endometrial polyps malignant?

Endometrial polyps are a frequent pathology encountered during pelvic sonography and diagnostic hysteroscopies. The true incidence of malignant endometrial polyps is unknown. The estimations range from 0.5 to 4.8%. The objective of this study was to investigate the frequency of malignant endometrial polyps, and to characterize the hysteroscopic image of these polyps.

The study included 300 consecutive women with endometrial polyps who underwent hysteroscopic polypectomy. Patients' characteristics, operative findings, and pathology reports were analyzed.

Four of the 300 endometrial polyps removed by operative hysteroscopy were malignant (1.3%). Patients with malignant polyps were symptomatic peri- or postmenopausal women. All asymptomatic polyps in this series were found to be benign. We could not identify any distinct hysteroscopic feature of malignancy.

Our study shows that about 1.5% of endometrial polyps may be malignant. This finding reinforces the indication for removal of symptomatic endometrial polyps, preferably by a hysteroscopic procedure. The significance of asymptomatic uterine polyps has still to be determined.