Endometrial cancer is cancer of the lining of the womb or uterus. It is the most common type of gynaecological cancer in high-income countries like Australia, and Australian women have a 1 in 40 chance of being diagnosed with endometrial cancer before their 85th birthday. Each year, there are more than 3,000 new cases and 550 deaths from endometrial cancer in Australia.
Endometrial cancer is most common in women aged 60-80 years and it only affects women who have not had a hysterectomy to remove their uterus. Women with a family history of endometrial cancer are at a greater risk of developing endometrial cancer themselves. Women who have a defect in one of the genes known as ‘mismatch repair genes’ have a greatly increased risk of developing endometrial (and bowel) cancer. However, these genetic defects are rare and other changes in genetic sequences likely play a role in endometrial cancer development. Other known risk factors include use of oestrogen replacement therapy, tamoxifen and obesity. In contrast, pregnancy, breastfeeding, use of the contraceptive pill and, potentially, use of combined menopausal hormone therapy all reduce risk.
Unlike most other types of cancer, rates of endometrial cancer are increasing and more women are being diagnosed with this cancer every year. This is probably due in part to the increasing prevalence of obesity in the population. Although survival rates for endometrial cancer are very good overall – the chance of a woman surviving for at least five years after her diagnosis is 83% – the numbers of women dying of endometrial cancer are increasing. Concerningly, it is predicted that endometrial cancer diagnoses and deaths will continue to rise significantly over the next decade. Some types of endometrial cancer are much more aggressive and survival rates for women with these cancers are very poor. Because these aggressive types are less common we do not know as much about what causes them as the less aggressive types.
Poor outcomes for the more aggressive endometrial cancer types may be in part due to a lack of drug treatment options. Indeed, only five drugs have received approval for endometrial treatment by the Federal Drug Administration (USA), while 55 drugs have breast cancer treatment approval. Moreover, since 1971 only two drugs have been approved for endometrial cancer treatment.
There is currently no screening test for endometrial cancer and, aside from reducing rates of obesity, we do not have a simple method to prevent women from developing it.