Summary: Women who know their genetic risk profiles for breast cancer report feeling less stress and fewer regrets following finding out the information than women who decide not to find out about their genetic risk.
Source: University of New South Wales
No-one likes to receive bad news, especially when it’s related to health.
But a recent study of women at risk of developing breast cancer suggests knowing your genetic risk profile does not lead to long-term distress and leads to fewer regrets than not wanting to know about it in the first place.
The research led by UNSW Sydney looked at how the communication of breast cancer risk affected women who had undergone genetic testing.
Lead author Dr Tatiane Yanes says the study focused on women who had undergone genetic testing to determine their polygenic risk score (PRS) – an analysis of 62 genetic variants on top of the two usual indicators of breast cancer found in the genes BRCA1 and BRCA2.
“PRS is a new type of genetic testing and genetic information that we haven’t been able to offer before because we’ve only been focusing on single genes,” says Dr Yanes, who conducted the study as part of her PhD at UNSW, and is now with University of Queensland.
“The vast majority of women who get screened for the BRCA genes come back negative, but that doesn’t always mean there’s no breast cancer risk. PRS looks much more broadly at variants in your DNA.”
A genetic variant is a small change to the base molecules that make up the DNA. On their own, they don’t necessarily mean greater risk. But the more variants found in the DNA, the greater the PRS.
“Past studies have shown that getting a PRS for breast cancer has the potential to improve health outcomes,” says Dr Yanes.
“But this is the first time that we have looked at how women who receive this information react. Does it cause more stress, or does it reduce it, and can it bring about positive behaviours in women who have either already been diagnosed with it or have a family history of breast cancer?”
Of the 208 study participants, 165 women (80 per cent) agreed to receive their PRS while the remaining 43 participants declined to be informed.
Among the women who agreed to be told their scores (dubbed ‘receivers’), 104 were given a high-risk score, while the remaining 61 were assessed as low-risk.
Not surprisingly, the study found that women with higher PRS experienced slightly more distress and anxiety upon receiving their result than those with a low PRS, “but it wasn’t really that big a gap to actually warrant additional psychological support,” Dr Yanes says.
But surprisingly, when the researchers compared the psychological outcomes of the women who opted to receive their PRS with those who declined, more women in the latter group reported regret about their original decision not to find out.
“Those who had received the results reported basically minimal regret. In fact, more than half of them actually had a score of zero, which means no regret at all,” says Dr Yanes.
“But the average regret score for those who didn’t receive that PRS result was around 38 out of 100 when compared to an average score of just 9 in the ‘receivers’ group.”
The researchers gathered the results in follow-up questionnaires at two weeks and 12 months after calculating the PRS scores, and they measured the regret using a validated method known as the Decision Regret Scale.
Among the women who declined to find out their PRSs, reasons included being “happy with their lives right now”, or that they were “already aware of breast cancer risk” and that the “test will not tell them when they will develop breast cancer”. Other reasons included not being able to attend the appointment in person and concern over how they would handle it emotionally.
Dr Yanes says the results will help clinicians and genetic counsellors to equip women with the tools to make an informed decision about whether or not to get a PRS result.
“We want doctors to be able to provide women with clear information outlined in decision aids that explains what the PRS is and the type of access women have to these genetic services,” Dr Yanes says.
“What we don’t want is that people decline information out of fear, or aren’t able to make an informed decision because they may not fully understand the information or what the implications for them are.”
Following on from the study, Dr Yanes will provide clinicians around the country with best practice guidelines on how to deliver personalised cancer risk management to women undergoing PRS genetic testing.
Breast cancer polygenic risk scores: a 12-month prospective study of patient reported outcomes and risk management behavior
To prospectively assess patient reported outcomes and risk management behavior of women choosing to receive (receivers) or decline (decliners) their breast cancer polygenic risk score (PRS).
Women either unaffected or affected by breast cancer and from families with no identified pathogenic variant in a breast cancer risk gene were invited to receive their PRS. All participants completed a questionnaire at study enrollment. Receivers completed questionnaires at two weeks and 12 months after receiving their PRS, and decliners a second questionnaire at 12 months post study enrollment.
Of the 208 participants, 165 (79%) received their PRS. Among receivers, there were no changes in anxiety or distress following testing. However, compared to women with a low PRS, those with a high PRS reported greater genetic testing–specific distress, perceived risk, decisional regret, and less genetic testing–positive response. At 12 months, breast screening and uptake of risk-reducing strategies were consistent with current Australian guidelines of breast cancer risk management. Reasons for declining PRS included being unable to attend the appointment in person and concerns over potential emotional response.
The outcomes of the study provide insight into women’s responses to receiving PRS and highlight the issues that need to be addressed in the associated model of genetic counseling.