Preventing Female Cancer in Women With Lynch Syndrome

What can you do to prevent gynecologic cancers if you have Lynch syndrome?

While unfortunately, we don't have ways to prevent cancer for people with Lynch syndrome—or without Lynch syndrome for that matter—we do know of some things you may be able to do which can reduce your risk of developing cancers of the ovaries or uterus. We also know of ways to test for female cancers, and by doing so, hope to find these cancers in the earlier more treatable stages.

Overview

Lynch syndrome is also known as hereditary nonpolyposis colorectal cancer syndrome (HNPCC). It is an inherited condition in which abnormalities in genes can be passed down from generation to generation.

The syndrome is related to changes in five genes: MLH1, MSH2, MSH6, PMS2, and EPCAM. These gene changes are inherited in an autosomal dominant fashion, meaning that you only need to inherit a mutated gene from one of your parents to face an increased risk of the syndrome. Lynch syndrome is thought to be responsible for 3% to 5% of all cases of colon cancer and 2% to 3% of all cases of endometrial cancer. The average age of developing colon cancer is 44 to 61 in someone with Lynch syndrome, as compared with age 69 in the general population.

Cancer Risks

General cancer risks for people with Lynch syndrome include:

• Colorectal cancer: 20% to 80%
• Stomach cancer: 1% to 13%
• Liver and bile duct cancer: 1% to 4%
• Bladder, kidney, and ureter cancer: 1% to 18%
• Intestinal cancer: 1% to 6%
• Pancreatic cancer: 1% to 6%
• Brain cancer: 1% to 3%

Risk of female pelvic organ cancers include:

• Endometrial cancer: 15% to 60%
• Ovarian cancer: 1% to 38%

This condition predisposes people to some other cancers as well, such as breast cancer.

The risk of different types of cancer varies by the gene mutation, so your risk is best discussed with your healthcare team.

Lowering the Risk of Cancer

When talking about reducing risk, it's important to first make a distinction. Most screening tests you will hear about are a form of early detection. These tests do not prevent cancer, or even lower the risk that you will develop cancer. Rather, they increase the chance that a cancer will be discovered when it is smaller. And most cancers are more treatable and perhaps even curable when they are small.

In contrast, there are things people can do to reduce their risk of developing cancer in the first place. Eating a healthy diet and exercising fall into this category. Colon cancer screening, however, is somewhat unique among cancer screening tests. It offers the chance to find a cancer early—early detection—but may also aid in prevention when precancerous tumors are found and removed before they turn into cancer.

General Prevention Measures

It's important to note that women with Lynch syndrome, in addition to other measures that will be discussed, should undergo cancer screening tests that women without Lynch syndrome receive. In fact, it is important to remember to care for health issues that could occur if you did not have Lynch syndrome. For example, women with hereditary breast cancer sometimes become so focused on breast cancer prevention that they forget to follow preventive screening for colon cancer as it seems "less important."

Keeping this in mind, it is necessary for women with Lynch syndrome to talk to their physician about medical concerns unrelated to Lynch syndrome. For example, it is still important to talk about heart disease prevention even though this syndrome does not raise the risk of heart disease, simply because everyone is at risk.

Additional Cancer Prevention Measures

In order to see what measures could be taken to decrease the chances of being affected by the increased genetic risk of Lynch syndrome, researchers have looked at the possible benefits of several screening tests.

Reducing Ovarian and Uterine Cancer Risk

There are several different options for reducing the risk of dying from ovarian or uterine cancer for women with Lynch syndrome. The 2013 Lynch syndrome recommendations by a group of European experts note that prophylactic hysterectomy (removing the uterus) and bilateral oophorectomy (removing both ovaries) prevents the development of endometrial and ovarian cancer. They say it should be discussed with those who have completed their families, especially after the age of 40 (when the risk of these cancers is increased). The U.S. Multi-Society Task Force on Colorectal Cancer and other organizations are in agreement with this.

A 2011 study focusing on a cost analysis of different approaches found risk-reducing surgery to be the most cost-effective approach.

Approaches to reduce the risk of dying from these cancers include:

• Annual gynecologic examinations
• Annual screening using endometrial biopsy, transvaginal ultrasonography, and serum CA 125 testing
• Surgical removal of the uterus, ovaries, and fallopian tubes

The U.S. Multi-Society Task Force on Colorectal Cancer says the most invasive option (surgery) results in the lowest cancer risk and the least invasive option (annual exams) results in the greatest cancer risk.

Reducing the Risk of Other Cancers

There are many screening considerations for people with Lynch syndrome for early detection of other cancers. For example, yearly or bi-yearly colonoscopies are recommended beginning at age 20 to 25 or five years less than the age at which a relative developed the disease. Talk to your doctor about these screening tests to determine what is right for you.