The last week of September marks an important moment dedicated to raising awareness about hereditary cancers. This time offers an opportunity to educate people about the genetic factors that can lead to certain types of cancer, highlighting the role family history plays in cancer risk.
Cancer is not directly inherited from parent to child, but having a family history of cancer can increase a person’s likelihood of developing the disease. Cancer tends to fall into three main categories: hereditary, sporadic, or familial, depending on the factors contributing to its development.
In the case of hereditary cancer, a single inherited genetic mutation plays a key role. This type of cancer involves a specific genetic alteration passed down through generations, leading to a higher risk of cancer within families. Individuals born with this genetic change have a significantly greater likelihood of developing cancer than the general population. Some cancers, such as ovarian, pancreatic, medullary thyroid cancers, and pheochromocytoma, are more commonly associated with hereditary risk.
On the other hand, sporadic cancer arises from DNA changes that occur by chance, often influenced by environmental factors. These include things like smoking, aging, and exposure to carcinogens. This type of cancer does not involve inherited genetic mutations, and examples of sporadic cancers include lung, papillary thyroid, and cervical cancers.
Familial cancer is the third category, where cancer clusters within a family. This clustering may be due to shared genetic and environmental factors, with lifestyle choices such as diet, smoking, and other common exposures playing a role. Cancers like breast, prostate, and colon are more likely to follow this pattern of occurrence within families.
When considering genetic testing for hereditary cancer risk, it’s important to understand who may benefit most. Although not everyone is a candidate, genetic testing may be advisable if there is a history of cancer diagnosed at a young age, particularly under 50, or if multiple closely related family members on the same side have had cancer. Testing might also be considered if cancer has affected multiple generations or if one individual has had multiple types of primary tumours.
The National Comprehensive Cancer Network (NCCN) provides guidelines to help determine who may be a good candidate for testing. If your family history suggests a hereditary risk, it’s a good idea to consult with your healthcare provider, who can guide you through the implications of genetic testing. For those worried about potential discrimination due to genetic results, federal protection is available under the Genetic Information Nondiscrimination Act (GINA), though it’s worth noting that these protections vary by state and may not cover all forms of discrimination.
The process of genetic testing begins with a consultation with your healthcare provider, such as a genetic counsellor, to review your family history. This helps determine which specific tests will be most useful. After the consultation, your DNA sample is collected, either through a blood sample, saliva, a buccal (cheek) swab, or sometimes a skin biopsy. The results are then sent to the healthcare provider who ordered the test, and they will review these findings with you in detail.
When it comes to results, there are three main possibilities. A positive result, also referred to as pathogenic or likely pathogenic, means a genetic mutation has been identified that increases the risk of specific types of cancer. A negative result indicates no significant genetic mutations were found, although this can have different implications based on the individual’s family and personal history of cancer. Finally, the test could reveal variants of unknown clinical significance (VUS), which means a genetic change was detected, but there is not enough information to determine whether it increases the cancer risk.
National Hereditary Cancer Week serves as a reminder of the importance of understanding our genetic health. Speaking with a healthcare provider and considering genetic testing can help individuals take the necessary steps to assess and manage their cancer risk.
EDX Medical Group Plc (AQSE:EDX) is a global specialist in digital clinical diagnostics; developing and supporting high-performance products and services to provide cost-effective prediction of disease risk, inform clinical decision-making, enable personalised healthcare and accelerate the development of new medicines for cancer, neurology, heart disease and infectious diseases.
