Some people develop cancer because they are born with mutated genes that can lead to cancer. This type of gene is typically inherited from the father or mother, and it is called hereditary cancer. All cancers are believed to be caused by gene mutations, but in most cancers, these changes in gene structure take many years to occur. People who develop hereditary cancer sometimes develop cancer at much younger ages because their gene mutation was present at birth.
Every person is born with two sets of genes, one from each parent. The function of a human gene is to instruct the behavior of cells. When cells become damaged by disease or environmental toxins, healthy genes will direct cellular rejuvenation, or in some cases, cellular death. When genes are not functioning properly, cellular behavior becomes abnormal, which can sometimes lead to cancerous growths.
Gene damage that is extensive enough to cause cancer development may take decades to occur, if it occurs at all. For people who have hereditary cancer genes, the risk of developing cancer is much higher, and they may develop cancer much earlier in their lives. Most research shows that people who have mutated genes at birth are at double the risk of cancer as compared to the rest of the population.
Hereditary cancers seem to be linked to the sex of the gene carrier. Hereditary cancers that are commonly found in men include prostate and colon cancer. In women, the most common types of hereditary cancers are breast and ovarian cancers. Though other forms of the disease can sometimes be linked to hereditary cancer, they are much rarer.
Medical science has developed ways to determine if people may be at risk for hereditary cancer. This is typically done by a process called genetic testing. Genes are extracted from the patient, and then are studied in a laboratory to determine if any mutations are found. This type of testing is very extensive and costly, and usually is not done unless there are indications that a person may be at risk.
Before performing genetic testing, most patients first undergo genetic counseling. These sessions are designed to determine if a person is at high risk for hereditary cancers. Doctors typically want extensive information on the health of the patient’s parents, grandparents, or other family members. Generally, they want to determine how many relatives may have had cancer, what type of cancer developed, and their age when the cancer was found. This type of information can sometimes indicate if there is a history of cancer within a family.