Genetics and Treatment Type Key Factors in Second Cancer Risks Among Childhood Cancer Survivors

Recent research from St. Jude Children's Research Hospital highlights that the risk of developing a second cancer after childhood cancer treatment is primarily influenced by genetic predisposition and the type of therapy received. Utilizing data from the extensive St. Jude Lifetime Cohort Study (St. Jude LIFE) and the Childhood Cancer Survivor Study (CCSS), scientists have quantified how these factors contribute to secondary cancer risk, which remains the leading cause of mortality among long-term survivors. The study reveals that radiation exposure during treatment is the most significant contributor, accounting for over 40% of secondary cancer risk, prompting a shift toward minimizing radiation doses in modern therapies.

Furthermore, the research uncovers that genetic factors play an influential role, sometimes surpassing the impact of chemotherapy. Using polygenic risk scores—assessments based on common genetic variants—the study found that genetic predispositions could account for up to 37% of the risk for certain second cancers. This is a groundbreaking finding, indicating that genetics should be considered alongside treatment history when assessing survivor risk.

Lifestyle factors such as diet and exercise appear to contribute less to secondary cancer risk at younger ages, with their effects possibly becoming more apparent later in life. Nonetheless, promoting healthy habits remains crucial for overall long-term health.

The findings suggest that personalized follow-up care, including increased screening for those with strong genetic predispositions, could improve early detection and intervention for secondary cancers. This research emphasizes the importance of integrating genetic screening into survivorship care and tailoring treatment strategies to reduce long-term risks.

Overall, this study enhances our understanding of how genetic and treatment-related factors interplay in cancer recurrence, guiding more effective, individualized survivor care to extend life expectancy and improve quality of life.

Source: https://medicalxpress.com/news/2025-05-genetics-therapy-cancer-childhood-treatment.html