Key takeaways
- A family history of cancer is a lot less common than you might think
- If you think you might have a family history of cancer, visit your GP, who might refer you to a genetic counsellor or other specialist
- Genetic counselling can help you confirm a family history of cancer, and support you in the next steps
- If you meet a certain level of risk, you might be offered genetic testing
With one in two people being affected by cancer in their lifetime, it’s highly likely that, in any family, at least one relative will be diagnosed with the disease. However, for most of us, cancer isn’t going to be hereditary. Around 90–95% of cancers develop as a result of a combination of risk factors, including ageing and lifestyle, and not because of an inherited altered gene. Yet, if a close family member has been diagnosed with cancer, you may be worried about your own risk. Likewise, if you’ve been diagnosed with cancer yourself, you may worry about what this means for other members of your family. In this article, Perci’s Lead cancer nurse specialist, Rachel Rawson, and Consultant genetic counsellor Dr Vishakha Tripathi, share their advice about facing a family history of cancer.
How to know if you have a family history of cancer
Rachel Rawson, Lead Cancer Nurse Specialist
While cancer is not usually inherited, there are some types, mainly breast, ovarian, colorectal and prostate cancer, that can be strongly influenced by genes and can run in families.
Rachel Rawson, Lead Cancer Nurse Specialist
While cancer is not usually inherited, there are some types, mainly breast, ovarian, colorectal and prostate cancer, that can be strongly influenced by genes and can run in families. Others, such as cervical cancer and lung cancer, are less likely to be related to an inherited altered gene. If you are concerned about cancer in your family, it can be helpful to look at your family tree. It’s likely that a cancer gene is present in a family if:
- There are two or more close blood relatives on the same side of the family (your mother’s or your father’s side) with the same type of cancer, or with particular types of cancer that are known to be linked, e.g., breast and ovarian cancer, or bowel and womb cancer
- Cancers are occurring at relatively young ages
- A close relative has had two primary occurrences of the same cancer type
Additionally, specific cancer types might have features that raise the possibility of inherited risk, such as triple negative breast cancers, although this doesn’t necessarily mean there will be a family history.
The first step to investigating a family history of cancer
If close family members have developed the types of cancer mentioned above and you’re worried that you might develop cancer yourself, you should contact your GP. They’ll ask about your family history, likely including the age of your relative when they were diagnosed and the type of cancer they have had. If they think there’s a chance you have an increased risk of developing cancer, they’ll refer you to a genetic counsellor, family cancer clinic or a cancer specialist.
What is a genetic counsellor?
Dr Vishakha Tripathi, Consultant genetic counsellor
Genetic counselling is the art and science of collecting and interpreting complex scientific and medical information, relaying it to the individual and their family in an understandable way, and offering them appropriate options with their informed consent. Genetic counselling also involves supporting patients in coping with and adjusting to the information, and sharing it with their families. Essentially it’s about navigating the decision-making process around what they access, when and why, with them. For example, a couple worried about passing on an inherited risk of cancer, might want to talk about reproductive options, while someone not thinking about starting a family might want to discuss when to choose risk-reducing surgeries.
People read a lot, they hear a lot and they often come with preconceived notions about hereditary cancer risk and family history. It’s my job to unpick what they already know, put it into context, then start to rebalance that information for them.
Dr Vishakha Tripathi, Consultant genetic counsellor
What do genetic counselling sessions look like?
During an initial conversation, I try to gather some medical and surgical history from the patient that could be relevant, as well as the same information on their relatives across a minimum of three generations. This is also an opportunity to talk about their main anxieties. Why are they seeking genetic counselling? What are their main questions? People read a lot, they hear a lot and they often come with preconceived notions about hereditary cancer risk and family history. It’s my job to unpick what they already know, put it into context, then start to rebalance that information for them. I’ll make a formal risk assessment and give them information about what their risk looks like, quantifying that if possible. We’ll also talk about what they could do to address risks.
The second part of our work together is psychological exploration. We’ll talk about why they feel the way they do about their level of risk, what they are going to do with the information and how they’re going to share it. Inherited risk is shared risk, so some of the information might be relevant to other family members, including their children if they have them. It can be hard to be the messenger of that news, so we come up with a plan. Thinking about their long-term wellbeing is also part of the counselling process. Ultimately it’s about taking the patient through this journey safely and with support.
When will someone be offered genetic testing?
If a patient meets a certain level of risk, I will order genetic testing. We each have 20,000 genes and not all genetic alterations raise cancer risk. Some might give you almost a 100% risk of developing a certain type of cancer, while others carry a minimal risk. If the patient chooses genetic testing, we’ll have a conversation about which genes would be the most informative to test, and why.
The process is a bit different depending on whether the patient actually has cancer or is just being proactive. Genetic test results are often not clear cut, and if the person is healthy, it can make interpretation of the results complex. However, if a genetic alteration was found, we would discuss what that means in terms of personal risk and management options, e.g., screening or risk-reducing surgery.
Find out more about specialist cancer nursing. For more information about Dr Vishakha Tripathi, visit DNA Connect.
While we have ensured that every article is medically reviewed and approved, information presented here is not intended to be a substitute for professional medical advice, diagnosis, or treatment. If you have any questions or concerns, please talk to one of our healthcare professionals or your primary healthcare team.