How often is colorectal cancer hereditary?
Exact percentages of how high your own risk is of developing colorectal cancer cannot be calculated per se. However, you can estimate your risk on the basis of the general risk factors and, compared to your own age group, classify whether you have a rather increased or rather decreased risk. As with all cancers, genetic risk factors naturally include the fact that it is a disadvantage if a first or second degree relative is already ill.
Furthermore, the presence of two significant syndromes must be checked: Familial polyposis syndrome (FAP) and HNPCC syndrome (hereditary non-polyposis colon cancer). The latter is the most common hereditary colorectal cancer and accounts for 5% of all colorectal cancers. Three-quarters of those affected by this genetic abnormality (mutation) develop colon cancer.
The less common FAP, on the other hand, has a 100% probability of developing colon cancer. Anyone who has frequent cases of intestinal cancer should undergo genetic testing to find out whether it is a genetic disease.
