Frequent Polyp Diagnoses in Relatives Linked to Increased Colorectal Cancer Risk

A study leveraging data from Swedish family cancer datasets has shown a significant association between the frequency of polyp diagnoses in family members and an increased risk of colorectal cancer (CRC), particularly early-onset CRC.

 Published in Gastroenterology, the findings, based on more than 5 decades of follow-up involving 11.7 million individuals, emphasize the need for personalized CRC screening strategies tailored to family history. 

The analysis revealed that individuals with one first-degree relative (FDR) who had a single polyp diagnosis had a 1.4-fold increased risk of overall CRC (95% CI, 1.3–1.4) and early-onset CRC (95% CI, 1.3–1.5) compared to those without a family history of colorectal tumors. However, the risk was substantially higher when the FDR had frequent (≥2) polyp diagnoses. In this group, the overall CRC risk rose to 1.8-fold (95% CI, 1.8–1.9), and the early-onset CRC risk increased to 2.3-fold (95% CI, 2.0–2.6). 

Risk escalated further when multiple relatives were involved. For individuals with 2 or more FDRs with frequent polyp diagnoses, the overall CRC risk was 2.4-fold (95% CI, 2.2–2.7), while the risk for early-onset CRC increased nearly 4.0-fold (3.9, 95% CI, 2.8–5.3). 

“Younger age at polyp diagnosis in first-degree relatives was associated with a greater risk of CRC,” the study noted. Additionally, second-degree relatives influenced CRC risk only when there were frequent polyp diagnoses. 

The researchers concluded, “These findings underscore the need for more personalized CRC screening strategies that are tailored to individuals with a family history of polyp.” 

These results suggest that clinicians should consider both the frequency of polyp diagnoses and the family member’s relationship when assessing CRC risk and tailoring screening recommendations.

Reference
Hu Y, Kharazmi E, Liang Q, Sundquist K, Sundquist J, Fallah M. Risk of colorectal cancer associated with frequency of colorectal polyp diagnosis in relatives. Gastroenterology. Published online January 10, 2025. https://doi.org/10.1053/j.gastro.2024.12.030