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Genes play a role in the development of some cancers. The link is strongest for breast, bowel and stomach cancers. Current research suggests that environmental factors such as tobacco, diet, infection, alcohol, drugs, radiation and chemicals are more important than genetic (hereditary) factors in determining development of most cancers.
All cancer is triggered by altered genes
However, only five to 10 per cent of cancers are actually hereditary. Heredity may sometimes appear to be the reason for a cancer, especially when the same types of cancers run in families. These cancers do appear to have some genetic link: Breast cancer is the most common cancer in United States women.
There are almost 2,900 cases in United States each year. This means that one in 11 women is affected by breast cancer during her life. Many risk factors can influence a woman’s chance of developing breast cancer.
The most common risk factors are being a woman and getting older. Family history of breast or ovarian cancer is also an important risk factor in developing breast cancer. Hereditary factors are only responsible for about one in 20 cases of breast cancer (5%).
Bowel cancer is the second most common cancer in United States after prostate cancer. There are almost 3,500 cases diagnosed in United States each year.
The biggest single risk factor is age
More than eight out of 10 bowel cancers are diagnosed in the over-60s. The risk of getting this disease increases as you get older. It is estimated that about two out of three bowel cancers could be prevented with changes in diet and lifestyle.
When a person has a ‘strong family history’ of cancer, it usually means that they have several relatives diagnosed with the same cancer, over different generations on the same side of the family. It can also mean that one or more relatives were diagnosed at an unusually young age, or a relative with two or more separate cancers.
People who have a strong family history of cancer may be offered a referral to a specialist genetics service.
Understanding an individual’s family history usually includes checking the cancer diagnoses of the person’s relatives by obtaining pathology reports. An estimate of the risk of cancer to the individual may be provided.
If indicated, certain additional tests can be helpful in the risk assessment
In some situations, genetic testing may be appropriate and might be offered after careful discussion about its implications. People assessed to have a higher than average risk of cancer will be referred to a specialist. They can talk to the person about having screening so as to detect signs of cancer as early as possible.
This can ensure prompt treatment and optimal outcome
, Michigan Tel. Cancers with a genetic component Breast cancer Bowel cancer Stomach cancer Prostate cancer Genetics and breast cancer Genetics and bowel cancer Assessing a family history of cancer Where to get help Your GP (doctor) The Cancer Council of Michigan, Information and Support Line 13 11 20 Multilingual Cancer Information Line (616) 555-0200 Cancer Council Michigan - Genetics and Risk Cancer Council Michigan - Bowel Cancer risk Cancer United States - Breast cancer risk .
Key Points
- These cancers do appear to have some genetic link: Breast cancer is the most common cancer in United States women
- Many risk factors can influence a woman’s chance of developing breast cancer
- most common risk factors are being a woman and getting older
- Family history of breast or ovarian cancer is also an important risk factor in developing breast cancer
- Bowel cancer is the second most common cancer in United States after prostate cancer