All cancers are caused by changes to materials in our bodies called “genes.” These are units of information in every cell of our bodies. Genes tell our bodies which proteins to make based on the type of cell and its needs. When genes themselves are damaged, they can develop changes called “mutations.” When mutations occur in the damage-controlling genes, cells can grow out of control and cause cancer.
While for most people who develop cancer, the cancer-causing gene mutations happen over the course of a lifetime. Some people are born with a gene mutation that they inherited from their mother or father. This damaged gene puts them at higher risk for cancer. When cancer occurs because of an inherited gene mutation, it is referred to as “hereditary cancer”.
So it basically comes down to 3 questions:
If someone in my family has cancer, am I likely to get cancer, too?
Not necessarily. Only about 5 to 10 percent of cancers are caused by harmful mutations that are inherited. In families with an inherited cancer-causing mutation, multiple family members will often develop the same type of cancer. The remaining 90 to 95 percent of cancers are caused by mutations that happen during a person’s lifetime as a natural result of aging and exposure to environmental factors, such as tobacco smoke and radiation. These cancers are called “non-hereditary” or “spontaneous” cancers.
If no one in my family has had cancer, does that mean I’m risk-free?
No. Most cancers are caused by genetic changes that occur throughout a person’s lifetime as a natural result of aging and exposure to environmental factors, such as tobacco smoke and radiation. Other factors, such as what kind of food you eat, how much you eat, and whether you exercise, may also influence your risk of developing cancer.
Family cancer syndromes – when should I worry?
When many cases of cancer occur in a family, it is most often due to chance or because family members have been exposed to a common toxin for example tobacco. Less often, these cancers may be caused by an inherited gene mutation causing a family cancer syndrome.
Certain symptoms indicate the family cancer syndrome, such as
- Many cases of an uncommon or rare type of cancer (like kidney cancer)
- Cancers occurring at younger ages than usual (like colon cancer in a 20 year old)
- More than one type of cancer in a single person (like a woman with both breast and ovarian cancer)
- Cancers occurring in both of a pair of organs (both eyes, both kidneys, both breasts)
- More than one childhood cancer in a set of siblings (like sarcoma in both a brother and a sister)
- Cancer occurring in the sex not usually affected (like breast cancer in a man)
Expert Advice:We recommend you to have regular health checkups regardless of whether Cancer runs in the family or not. While every individual is suggested to have a full physical exam once a year, women are required to take an extra mile and conduct a breast self-exam every month.