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Study Reveals Personalized Screening Ages for Colorectal Cancer Based on Genetic and Gender Factors

New research shows risk-adapted screening can vary by as much as 24 years for average-risk individuals without a family history of colorectal cancer (CRC).

A recent cohort study of 242,779 individuals with no prior family history of colorectal cancer (CRC) has unveiled the potential for personalized screening ages, demonstrating that risk-adapted starting ages can vary significantly based on sex and polygenic risk scores (PRS). The study employed a novel concept known as the “risk advancement period” (RAP) to determine how many years earlier or later individuals, particularly men compared to women, would reach comparable CRC risk levels. The results indicated that risk-adapted screening ages could differ by up to 24 years, even among individuals considered at average risk.

A new study, published in JAMA Network Open Journal, has addressed the question of how to translate risk variations in individuals without a family history of colorectal cancer (CRC) into personalized starting ages for screening. This research, which involved 242,779 participants with no previous CRC screening and no family history of the disease, demonstrated that risk-adapted starting ages can differ significantly based on sex and a polygenic risk score (PRS), which considers genetic factors. The study used the concept of the risk advancement period (RAP) to quantify the years by which men and individuals in different PRS groups would reach comparable risk levels compared to women and those in specific PRS deciles.

Key Findings:

  • The study included 242,779 participants aged 40 to 69 years, with a median age of 55 years and 55.7% women.
  • Over the course of the research, 2714 CRC cases were identified, with 758 CRC-related deaths.
  • Men had a 1.57-fold increased risk of CRC compared to women.
  • PRS played a significant role, with individuals in the lowest PRS deciles having half the risk and reaching equivalent risk levels 8 years older than those in the middle PRS deciles.
  • Individuals in the highest PRS decile had double the risk and reached equivalent risk levels 10 years younger.
  • RAP estimates revealed that men reached equivalent risk levels about 6 years earlier than women.
  • Risk-adapted screening ages could differ by as much as 24 years between men in the highest PRS decile and women in the lowest PRS decile.

Implications: The study highlights the potential for personalized screening ages based on individual risk factors. Current guidelines for CRC screening often do not consider these factors, leading to variations in screening recommendations in different countries. The findings suggest that using the risk advancement period concept could enable more precise and personalized screening recommendations based on factors like sex and genetic risk scores. However, challenges such as the cost of genetic testing and ethical considerations related to privacy and confidentiality must be addressed before implementing such an approach in routine clinical practice.

Conclusion: This study sheds light on the possibility of personalized screening for colorectal cancer, taking into account the unique risk profiles of individuals. The risk advancement period concept, which considers sex and polygenic risk scores, shows promise in providing tailored screening recommendations. However, further research and practical considerations are needed to determine the feasibility, cost-effectiveness, and ethical implications of implementing such an approach in healthcare settings.

Source: JAMA Network Open Journal