Genetic risk of cancer? Oncologist busts common misconceptions and explains the chances of developing hereditary cancer

If you have had a cancer case in your family, know what are the chances of you being at risk of cancer.

If someone has had cancer in the family, there is often fear surrounding it, creating unnecessary anxiety and making one assume that they too are at higher risk. While family history can increase genetic risk, assuming that one will automatically develop cancer just creates a lot of distress and emotional burden. It becomes critical to broaden one's horizon and truly understand what it means to be genetically predisposed, and that it does not, by default, mean a cancer diagnosis.

ALSO READ: Pancreatic cancer research hits major milestone: What is the disease and how to tell the signs?

To get a clear picture of what it means to have a genetic risk, HT Lifestyle reached out to Dr Randeep Singh, director and senior consultant oncology services, medical oncology, haemato oncology & BMT at Narayana Hospital, Gurugram.

“Genetics is an important contributing factor, but it is often misunderstood and can create unnecessary fear in the absence of proper information," Dr Singh said. Usually, there is a lot of confusion around the topic of genetic cancer risk. It is better to be well-informed rather than get overwhelmed by the misconceptions. Moreover, the oncologist also reminded that genetics is not the sole or dominant cause in most cases, lifestyle factors like habits, diet, environmental exposure, infections, or ageing also play a role.

Genes are inherited, and they play a role in how bodies function, including how the cells grow, divide and repair themselves, and if any defective gene is inherited, then the risk of cancer may run in the family. These are called hereditary or genetically mediated cancers. However, this does not mean cancer is inevitable. So it becomes critical to understand inherited genetic risk as it allows one to take proactive steps in terms of prevention, such as following a healthy lifestyle, going for regular screening and monitoring. When one is informed, fear reduces, and they become focused on prevention.

Chances

What are the actual chances of someone with an inherited genetic risk developing cancer? There's a major assumption that heredity plays a dominant role, but in reality, there's more to the story. As per the oncologist, inherited mutations make up only a fraction of cancer cases.

“Only a small proportion of cancers, around five to 15 per cent, are linked to inherited genetic mutations. The majority of cancers occur due to non-genetic causes.” Dr Singh revealed.

This is a big myth buster, recognising that the majority of cancers are not inherited, helps lower the unnecessary worry and anxiety, and instead shifts the focus to modifiable risk factors and regular screening.

The oncologist further shared about the patterns in a family's medical history that help to identify hereditary cancer risks. He elaborated, “Hereditary cancer is suspected when there are cancer cases among first-degree relatives (parents or siblings), multiple other family members affected, or cancer occurring at a younger age, typically before the age of 50.”

Genetic testing reveals the risks of heriditary cancer. (Picture credit: Freepik)

Common cancers related to genetic risk

There are certain cancers which are more closely associated with genetic risks. Dr Singh named: breast, ovarian, colon, uterine, and prostate cancers.

Genetic testing

The easiest way to dispel the anxiety is genetic testing.Dr Singh disclosed two situations when one should get genetic testing: “For patients already diagnosed with cancer who have a strong family history, and for healthy individuals who have close relatives affected by cancer.”

But in both cases, the doctor acknowledged that anxiety can be triggered, as a cancer diagnosis itself is overwhelming. On top of that, the possibility of a genetic condition can worsen the fear, with people worrying about passing it to their children or other family members. Overall, the entire experience can be very distressing.

To cope with this anxiety, Dr Singh recommended genetic counselling, which helps these people understand what the test involves, the possible outcomes, and the implications of the results, whether positive or negative, for family members. Post counselling then explains the results in detail and guides them on the next steps.

Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.