What Are the Chances of Inheriting Cancer?
There is a popular belief that cancer is hereditary and that if someone in your family was diagnosed with cancer, then all other close relatives are at risk. However, is this actually the case?
Dr. Marina
Oncologist
What is cancer?
Each cell in our body goes through its lifecycle. The cells divide, old cells die, and are replaced by the new ones. It is the principle that governs all the functioning of the human body. In the absence of this principle, wounds wouldn't heal, hair and nails wouldn't grow, and body organs wouldn't recover after disorders. However, cells sometimes start to mutate, and the process of cell division becomes uncontrolled. The malignant process begins only when there are a significant number of mutated cells and the body's defenses undergo a major disruption.
The likelihood of having these factors happen simultaneously depends on many parameters including geographical location, diet, life habits, and genetics. The cancer of specific body organs is not hereditary except in very rare cases (which will be mentioned below). People can only inherit a weak immune system and the ability of cells to develop more mutations than average.
According to research, only 5 to 10Β % of cancer cases are attributable to mutations inherited from parents.
What are hereditary types of cancer?
The most well-known type is the BRCA1 and BRCA2 genes mutation. Thanks to Angelina Jolie, many people have been made aware of this mutation. According to research, the presence of this mutation increases the chances of breast and ovarian cancer by 70Β %. The familial adenomatous polyposis (the formation of polyps in the colon) is considered hereditary, and, in 65Β % of cases, ends up developing colon cancer at a young age (by the age of 40). After that, the likelihood of polyps' cancerous mutation gradually decreases.
Lynch syndrome is a rare hereditary disorder with an almost 100Β % risk factor because almost 90Β % of those diagnosed with this syndrome develop colon cancer by age 50.
There are many cancer types, and it is practically impossible to research all of them in various generations of a single family. Therefore, medical professionals today recommend systemic cancer screening only to those who belong to one of the following groups:
- Those who had several consecutive cases of cancer of the same type in the same line of kinship
- Who had an incidence of cancer with one of their family members age 50 or younger
- Whose blood relatives had cancer of paired organs (kidneys, mammary glands, lungs)
Does it make sense to remove body organs in advance?
Let's consider the situation of Angelina Jolie, whose grandmother and mother died from ovarian and breast cancer. Typically, the risk of developing mammary gland cancer in women equals 13Β %. The genetic test results for Jolie have shown that her risk of developing this type of cancer is 87Β %.
With such test results, surgery to remove organs is recommended. However, for the moment, it is impossible to remove the intestine, kidneys, or lungs to prevent developing cancer. For this reason, such surgeries can be administered only for mammary gland cancer and tumors of the woman's reproductive system.
What should you do if you are at risk?
The mutations that lead to tumors can be identified through genetic testing. Today, there are more than 700 types of testing that can identify the risk of developing cancer. Oncologists can identify the tests that will work in your particular case.
The positive cancer test is not 100Β % reliable You can be healthy while your tumor markers can be increased β and conversely, tumor markers can be normal at the onset of cancer. However, if you have tested positive, you should have more screening tests.
When is the screening recommended and why might you need it?
There is no answer to the "when" question. As soon as you become worried, or if you find yourself genetically predisposed or notice any symptoms that disturb you, you should have a test done. Your genetic code doesn't change β if you have a mutation, it will be diagnosed at any age.
You will be able to discuss the results with your doctor and work out the plan of future tests to start therapy as early as possible in the negative scenario. For example, early diagnostics help 98Β % of women recover after breast cancer. Even bad genes are no longer your destiny, but just a signal to be on the lookout.
19 August 2021