Having a first-degree relative with colorectal polyps may increase a person’s risk of developing colorectal cancer (CRC), as found by a case-control study recently published in BMJ.
Study researchers used several national registrars in Sweden and a nationwide cohort known as ESPRESSO (Epidemiology Strengthened by histoPathology Reports in Sweden) to identify individuals for the analysis. A total of 68,060 patients with CRC were identified and matched to 333,753 individuals who served as controls.
Among patients with CRC, 8.4% had a first-degree relative with a colorectal polyp, while 5.7% of controls had a first-degree relative with a colorectal polyp.
A multivariate analysis showed that individuals who had a first-degree relative with a colorectal polyp had an increased risk of developing CRC (odds ratio [OR]=1.40; 95% CI, 1.35 – 1.45).
Individuals who had 2 or more first-degree relatives with a colorectal polyp had an even higher risk of developing CRC (OR=1.70; 95% CI, 1.52 – 1.90; P < .001), as did individuals who were younger than 50 years of age when a polyp diagnosis was made (OR=1.77; 95% CI, 1.57 – 1.99; P < .001). Individuals with at least 2 first-degree relatives with colorectal polyps and CRC had a particularly high risk of developing CRC (OR=5.00; 95% CI, 3.77 – 6.63; P < .001). Having at least 2 first-degree relatives with polyps especially raised the risk of having early-onset CRC before age 50 years (OR=3.34; 95% CI, 2.05 – 5.43; P =.002).
“After adjusting for family history of CRC, the siblings and children of patients with colorectal polyps are still at higher risk of CRC, particularly early onset CRC,” the study researchers concluded. “Early screening for CRC might be considered for first-degree relatives of patients with polyps.”
Song M, Emilsson L, Roelstraete B, Ludvigsson JF. Risk of colorectal cancer in first degree relatives of patients with colorectal polyps: nationwide case-control study in Sweden. BMJ. Published online May 4, 2021. doi:10.1136/bmj.n877