At first glance, saliva may not seem closely related to the risk of acquiring melanoma, but successful results from a pilot trial indicate that the genetic identification of higher-risk individuals could result in reduced rates of this cancer in hot spots such as northern NSW.
Some preliminary results from the trial have been presented at recent international cancer conferences, and more results will be presented at the Sydney Cancer conference and Australasian Epidemiological Association conferences in September 2016.
It is known that where we live affects our predisposition to melanoma: Australia and NZ have the world’s highest rates, with the greatest incidence in Queensland (and by association, far northern NSW), both nationally and internationally.
Who we are is also a key factor, as common genomic variants have a strong contribution to melanoma risk prediction.
Currently, the public is far more aware of the former risk factor than the latter, which is why this pilot trial* has such potential for improving prevention behaviours as well as psychosocial outcomes.
‘Precision prevention’ is how lead researcher Assoc Prof Anne Cust described it in a conversation with GP Speak.
“Direct to consumer testing is now available (particularly in the US) and advancing technologies have led to an explosion in knowledge about genomic risk factors for common, preventable diseases, particularly cancers,” Dr Cust said.
“Translation and implementation of genomic information has predominantly occurred in diagnostic and treatment settings. However, genomic risk information also presents an innovative opportunity to improve cancer risk prediction, cancer prevention and early detection on a population level.
“We are interested in conducting research on key questions that need to be addressed if this type of information becomes more mainstream in Australian healthcare. E.g. how much genomic information should the public be offered? What are the experiences of people who have received genomic information, and how does it impact them behaviourally and psychologically?
“How should we equip health professionals to deliver genomic information? What are the experiences of health professionals who deliver genomic information to patients?”
Such questions, which sit at the leading edge of modern medicine, inform a project, that began last year with the participation of 100-plus members of the public statewide. The pilot study, being conducted by researchers from The University of Sydney, aims at examining the “feasibility, acceptability and impact” of providing people with information on their individual genomic risk of getting melanoma.
The results so far indicate that overall there was found to be a positive impact in terms of some enhanced preventive behaviours, and no negative impact on skin cancer-related worry or psychological distress.
However, a much larger planned trial will focus on determining such impacts more conclusively.
More than 13,000 new cases of melanoma will be diagnosed in Australia this year, making it the third most common cancer in both men and women. During their lives, 1 in 14 men and 1 in 24 women will be diagnosed with melanoma at some time. While melanoma accounts for only 2 per cent of all skin cancers, it causes 75 per cent of skin cancer deaths.
In the pilot’s randomised controlled trial a sample of urban and regional NSW adults - including Northern Rivers residents - agreed to give a saliva sample for the purpose of the study.
Following analysis of the genetic material, the trial team provided personalised booklets outlining participants’ genomic risk of melanoma, and educational materials on preventative measures to reduce these. Telephone-based genetic counselling was also offered.
One example, for patient ‘John’, stated, “This booklet gives you an estimate of how likely you are to develop melanoma in the future. We call this an estimate of your remaining lifetime risk of melanoma.
“This booklet also describes how your remaining lifetime risk of melanoma was calculated, and what this risk means for you and your relatives… Based on your genetic risk, you are about 2.1 times more at risk of developing melanoma from now until the age of 85, than other men your age in NSW.
“This places you in a high risk category. However, this does not take into account non-genetic risk factors such as past sunburns…”
The booklets were also provided to the participants’ GPs and the participants were later asked whether they had discussed the information with their doctors, families and friends.
The results showed -
- 41 per cent of high-risk patients had communicated their risk information with health professionals, 83 per cent with family, and 55 per cent with friends
- 17 per cent of average-risk patients had communicated with health professionals, 65 per cent with family, and 42 per cent with friends
- 13 per cent of low-risk patients had communicated with health professionals, 79 per cent with family, and 54 per cent with friends.
The researchers concluded that while conversations about melanoma risk and prevention occurred most frequently with family members, the higher the genomic risk the more likely patients were to discuss preventive behaviours and early detection with medical practitioners.
One female patient in the study is said to have booked a skin examination for each time she has a Pap test.
“The reasons for not communicating genomic risk included: concern about causing worry and not feeling a need to share the information,” they added.
Participating patients reported high satisfaction with the personalised booklets and genetic counselling, according to the researchers, who concluded that, “Our results demonstrate feasibility and strong acceptability of providing personalised genomic risk of melanoma to the public, and suggest improvements to prevention behaviours.”
These improvements may include -
- seeking shade, and reducing time in the sun during peak times (11.00am-3.00pm in the warmer months)
- using sunscreen
- wearing a hat and protective clothing
- avoiding intentional tanning
- having a partner or medical practitioner check one’s skin.
Another important aspect of the pilot study has been seeking feedback from participating GPs via short telephone interviews about the booklet and asking how they feel their patient/s received the information provided.
GPs are also being asked broader questions, including -
- How is “genetics and genomics impacting on your practice and patient care in general”?
- Do patients show interest in genetic risk information?
- Should patients be given such information regardless of whether they request it?
- Should parents have children genetically tested?
- Could test results have either positive or negative impacts on emotions or behaviours?
- Are health professionals and the system prepared for the way genetics is influencing health care?
The research will generate high-quality evidence on potential new cancer prevention strategies using genomics, taking into account key stakeholders’ views, experiences and educational, support and training requirements.
This aspect of the pilot, titled Exploring the impact of delivering genomic risk information, is ongoing, and the participation of more GPs is invited by the research team.
For further information, contact Amelia Smit, Research Study Co-ordinator, on (02) 8627 1530 or
*Authors: Anne E Cust1,2 Amelia K Smit,1 David Espinoza,3 Rachael L Morton,3 Georgina Fenton,1,4 Lucinda Freeman,1,4 Kate Dunlop,4 Phyllis N Butow,5 Matthew H Law,6 Michael G Kimlin,7 Louise A Keogh,8 Suzanne Dobbinson,9 Judy Kirk,10 Peter A Kanetsky,11 Graham J Mann,2,12 Ainsley J Newson.13
- Cancer Epidemiology and Prevention Research, Sydney School of Public Health, The University of Sydney, Australia
- Melanoma Institute Australia, The University of Sydney, Australia
- NHMRC Clinical Trials Centre, The University of Sydney, Australia
- The Centre for Genetics Education, NSW Health, Sydney, Australia
- Centre for Medical Psychology and Evidence-based Decision-making, School of Psychology, The University of Sydney, Australia
- Statistical Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia
- The University of the Sunshine Coast and Cancer Council Queensland, Brisbane, Australia
- Melbourne School of Population and Global Health, The University of Melbourne, Australia
- Cancer Council Victoria, Melbourne, Australia
- Westmead Clinical School, and Westmead Institute for Medical Research, Sydney Medical School, The University of Sydney, Australia
- Cancer Epidemiology Program, Moffitt Cancer Center, Florida, U.S.
- Centre for Cancer Research, Westmead Institute for Medical Research, The University of Sydney, Australia
- Centre for Values, Ethics and the Law in Medicine, Sydney School of Public Health, The University of Sydney, Australia
