Endometrial hyperplasia: a clinician's review

Endometrial hyperplasia is considered present when the ratio of glandular to stromal tissue of the endometrium is greater than 1:1. Further differentiation is made into simple or complex hyperplasia with or without the presence of cytological atypia. Such changes are caused by excess or unopposed oestrogenic stimulation. Clinically endometrial hyperplasia is often asymptomatic but can present as abnormal uterine bleeding. Many cases are detected incidentally or following abnormal vaginal bleeding by an increase in the normal endometrial thickness on transvaginal ultrasonography (TVS). An endometrial biopsy can be obtained using a pipelle or at hysteroscopy, and examination of this allows a histological diagnosis. Cytological atypia mandates active intervention as its presence correlates with both a significant risk of progression to endometrial cancer as well as an increased rate of occult endometrial cancer. Hysterectomy is therefore the treatment of choice. The absence of cytological atypia confers a lower risk of malignant change. Thus management is more conservative. Progestogens are used to oppose the oestrogenic stimuli, coupled with ongoing surveillance.