••• CHAPTER 33^ Menopause^331
❍ What is the incidence of adenomatous or atypical hyperplasia in unopposed estrogen users?
10% per year.
❍ What risks of progression to cancer are associated with the various types of endometrial hyperplasia?
Simple hyperplasia without atypia 1%
Complex hyperplasia without atypia 3%
Simple hyperplasia with atypia 9%
Complex hyperplasia with atypia 30–50%❍ What percentage of atypical endometrial hyperplasia will progress to cancer within 1 year?
20% to 25%.
❍ What is the time required for endometrial hyperplasia to progress to cancer?
5 years.
❍ What is the risk of endometrial cancer in postmenopausal women not on HRT?
4 per 1000 (0.4%).
❍ What is the risk of endometrial cancer in postmenopausal women with abnormal uterine bleeding?
20%.
❍ How much higher is the risk of endometrial cancer in patients on unopposed estrogen compared with the
general population?
2 to 10 times higher, depending on dose and duration of exposure.
❍ How long does the risk of endometrial cancer persist after discontinuation of estrogen?
10 years.
❍ What characteristics of endometrial adenocarcinoma are present in patients on estrogen therapy?
Most lesions are low grade and early stage, and associated with better survival.
❍ What is the 5-year survival rate in women whose uterine cancer was diagnosed while they were taking
estrogen replacement therapy?
95%.
❍ How does progesterone counter effect estrogen on endometrial growth?
It decreases estrogen receptors, induces enzymatic conversion of estradiol to an excreted conjugate, estrone sulfate,
and suppresses estrogen-induced oncogene transcription.