Is endometrial cancer hereditary?

When it comes to endometrial cancer, I believe everyone is familiar with it. Endometrial cancer refers to a group of epithelial malignant tumors originating from the endometrium. It is one of the three most common malignant tumors in the female reproductive tract. Due to its anatomical and biological characteristics, endometrial cancer mostly grows slowly, metastasizes late, and has obvious symptoms such as menstrual disorders or irregular vaginal bleeding after menopause in the early stage. Most patients can seek medical treatment early, so the clinical prognosis is relatively good. It is reported that the overall 5-year survival rate is about 70%, among which the 5-year survival rate of clinical stage I patients can reach 85%.

However, there is a type of endometrial cancer that may cause the patient and her family to "run aground" with cancer again. It is hereditary endometrial cancer, which accounts for 5% of endometrial cancers, and the vast majority of them are related to the familial cancer syndrome Lynch syndrome, which is called Lynch syndrome-related endometrial cancer.

What is Lynch syndrome and what causes it?

Lynch syndrome is a familial cancer syndrome, an autosomal dominant hereditary disease caused by germline mutations in the DNA mismatch repair (MMR) gene. It occurs at an early age and has a high penetrance. It is mainly manifested by an increased risk of early-onset colorectal cancer, endometrial cancer, and a series of extracolonic cancers, including other gastrointestinal tumors (such as gastric, small intestine, and biliary tract cancers), urinary system tumors, and ovarian cancer.

How likely is Lynch syndrome to be inherited?

Everyone has two copies of the Lynch syndrome gene. One copy comes from the mother and the other from the father. Whichever parent you inherit a copy of the mutated gene from will cause Lynch syndrome. Therefore, a person who is diagnosed with Lynch syndrome has a 50% chance of passing the gene to her children. Lynch syndrome does not skip generations. The risk is the same for females and males.

Why is it important to diagnose Lynch syndrome?

Compared to the general population, 50% of women with Lynch syndrome have endometrial cancer as their first malignancy, which is diagnosed about 10 years earlier than non-hereditary endometrial cancers on average. Colorectal cancer and ovarian cancer, which have a poorer prognosis, are the most common. For a cancer patient, a diagnosis of Lynch syndrome indicates an increased risk of developing new cancers in the future. However, cancer risk can be reduced through early diagnosis and preventive measures.

Because Lynch syndrome is inherited, this diagnosis can also affect family members. If genetic testing is done to identify the specific mutation that causes Lynch syndrome, other family members can also be tested.