Background: Li-Fraumeni syndrome (LFS) is a rare genetic condition that increases lifetime risk for a variety of cancers in children and adults. LFS is due to an inherited mutation in the p53 tumor suppressor gene. While genetic testing may help LFS families better understand their cancer risks, decisions to undergo testing may be difficult given the psychosocial implications of testing and the lack of clarity about screening and surveillance methods that are most appropriate for LFS-related cancers. Previous research has shown decisional conflict, or one's perceived difficulty in making decisions about genetic testing, to be a strong predictor of p53 testing intention. However, little is known generally or specifically among LFS-affected families about the factors that predict decisional conflict. We tested a theoretical model of factors (Hall, Manne, Winkel et al., 2011) that contribute to decisional conflict, including genetic testing self-efficacy, genetics knowledge and testing pros and cons. Additionally, we expanded upon the model by assessing the contribution of risk perceptions and worry and the extent to which the model also predicts p53 genetic testing intentions.

Methods: Participants (N=139) in this study were from 27 LFS-affected families enrolled in a longitudinal study offering p53 genetic counseling and testing, including those affected (N=29) and unaffected (N=110) by cancer.

Results: Analysis using generalized estimating equations shows higher testing self-efficacy is associated with lower levels of decisional conflict (B=0.09, p<.01). Worry is also shown to moderate the effect of risk perception on decisional conflict (B=0.04, p<.01) whereby higher risk perceptions predict lower decisional conflict when worry is also high. Lower decisional conflict in turn, is associated with higher p53 genetic testing intention (B=1.04, p<.01). Those with more knowledge about genetics also had lower intentions to test (B=-0.10, p<.01).

Conclusions: These findings support previous research showing decisional conflict to be an important predictor of genetic testing intention among those at-risk of LFS and suggest decisional conflict may help further explain how psychological factors (e.g. perceived risk, self-efficacy, worry) impact genetic testing intention. Thus, these findings offer support for the development of decision aids for p53 genetic testing and suggest these aids should communicate risk and build self-efficacy in order to reduce uncertainty surrounding testing decisions. Additionally, results suggest that those with strong cognitive and emotional responses to risk will have more confidence in their decisions whether to test.

Citation Information: Cancer Prev Res 2011;4(10 Suppl):B10.