A Genomic Test for Colorectal Cancer Risk: Is This Acceptable and Feasible in Primary Care?

Abstract

Introduction: Genomic tests can predict risk and tailor screening recommendations for colorectal cancer (CRC). Primary care could be suitable for their widespread implementation. Objective: We aimed to assess the feasibility and acceptability of administering a CRC genomic test in primary care. Methods: Participants aged 45-74 years recruited from 4 Australian general practices were offered a genomic CRC risk test. Participants received brief verbal information about the test comprising 45 CRC-associated single-nucleotide polymorphisms, before choosing whether to undertake the test. Personalized risks were given to testers. Uptake and knowledge of the genomic test, cancer-specific anxiety (Cancer Worry Scale), psychosocial impact (Multidimensional Impact of Cancer Risk Assessment [MICRA] score), and impact on CRC screening behaviour within 6 months were measured. Results: In 150 participants, test uptake was high (126, 84%), with 125 (83%) having good knowledge of the genomic test. Moderate risk participants were impacted more by the test (MICRA mean: 15.9) than average risk participants (mean: 9.5, difference in means: 6.4, 95% confidence interval (CI): 1.5, 11.2, p = 0.01), but all scores were low. Average risk participants' cancer-specific anxiety decreased (mean differences from baseline: 1 month −0.5, 95% CI: −1.0, −0.1, p = 0.03; 6 months −0.6, 95% CI: −1.0, −0.2, p = 0.01). We found limited evidence for genomic testers being more likely to complete the risk-appropriate CRC screening than nontesters (41 vs. 17%, odds ratio = 3.4, 95% CI: 0.6, 34.8, p = 0.19), but some mediators of screening behaviour were altered in genomic testers. Conclusions: Genomic testing for CRC risk in primary care is acceptable and likely feasible. Further development of the risk assessment intervention could strengthen the impact on screening behaviour.

Preferences for a polygenic test to estimate cancer risk in a general Australian population

“…3 Research examining preferences for a cancer PRS have focused on single cancer types. 13,19,26,34 Our study is the first to examine how cancer type, as well as a multicancer PRS test, are traded off when choosing between alternative PRS testing approaches. Results from the MXL model showed a preference for a multicancer test and cancer types including breast cancer, prostate cancer, and bowel cancer whereas no significant preference was found for pancreatic cancer, lung cancer, or melanoma.…”

“…Although this is acceptable to specialist clinicians, there is mixed evidence as to whether this will be acceptable to patients. 14,18,19 Additional variables of concern to the public include privacy protections and the potential impact of genomic test results on life insurance plans. 12,13,16,20 Despite the importance of understanding public preferences regarding PRSs, there is a lack of data to adequately understand how these variables are traded off and the subsequent impact on implementation.…”

Responsible use of polygenic risk scores in the clinic: potential benefits, risks and gaps

“…PRS information could motivate risk-reducing health behavior, for example by prompting initiation of medication, screening, or lifestyle changes 27 . Although not focused on PRSs specifically, research on inherited cancer syndromes has shown improved screening adherence following disclosure of genetic test results 28 . Additionally, a recent study suggested that providing people with personal genetic results about obesity risk can alter cardiorespiratory and satiety physiologies, including perceived exertion and running endurance during exercise and perceived fullness after food consumption 29 .…”

Heterogeneity in how women value risk-stratified breast screening

“…Online communication of genomic results has not been explored in the clinical setting to date and development of a theoretical-based, online communication framework would be required to ensure a decision-empowered informed consent process. Work in other salient areas, including dynamic consent processes, 35 the role of GPs in polygenic risk assessments, 36 and a self-sampling approach to tissue collection, 37 are already in progress and look promising. A major policy decision that will affect the clinical efficacy and cost effectiveness of risk stratification is the age at which the risk assessment is offered.…”