Inherited genetic problems can cause less than 5 in 100 of all endometrial cancers. In these instances, defective gene changes may be passed down through families and we may see a higher number of family members with womb, breast, ovarian or bowel cancers.
The commonest of these problems is Lynch syndrome, an inherited condition which is caused by mutations (abnormal changes) in certain genes. People with this condition are at increased risk of different types of cancers including bowel cancer and endometrial cancer. To this end, all endometrial cancers currently routinely undergo three tests for mismatch repair (MMR), P53 and oestrogen receptor (ER) as a small percentage (less than 10% of cases). MMR deficiency reflects an abnormality in the ability to repair DNA. P53 is a tumour suppressor gene which, when mutated, fails to prevent uncontrolled cell division. Finally, ER is a cell receptor responsible for how cells respond to oestrogen in the body. These tests can highlight those women who may have Lynch syndrome.
The National Institute for Clinical Excellence (NICE) recommends testing for Lynch syndrome after a colorectal (bowel) cancer diagnosis. However, since womb cancer is often the first cancer that women with Lynch syndrome will have, anyone who is diagnosed with endometrial cancer should be offered screening for Lynch syndrome, even if there is no family history of the disease. This will be done by a pathologist. If Lynch syndrome is diagnosed, treatment and surveillance (regular monitoring) can be offered to reduce the risk of having another Lynch syndrome-associated cancer (in particular that of the bowel) or to identify it earlier. Your close relatives will also be offered screening.
There are other tests done for genetic assessment of endometrial cancer. One of these currently being deployed nationally is for POLE mutation testing. This is only conducted if endometrial cancers are MMR deficient or P53 mutant. POLE mutations usually only occur in 5-10% of endometrial cancers. Tumours affected by this usually have a better prognosis which can affect the extent of surgical management. These tests are quite complicated and are explained in another of our information leaflets.