A recent study has uncovered that individuals who experienced bleeding in the rectal area and then underwent a colonoscopy were significantly more likely, 8.5 times, to receive a diagnosis of colorectal cancer. The study underscores the critical importance of not dismissing such symptoms, even if there is no family history of the disease or if individuals do not meet the usual screening criteria.
The correlation was notably strong among patients below the age of 50, with 70% of them lacking a family history of colorectal cancer. Surprisingly, 88% of those who underwent a colonoscopy did so because of their symptoms rather than for routine screening purposes.
Sandra Kavalukas, a senior author and colorectal surgeon at the University of Louisville School of Medicine in Kentucky, emphasized the significance of taking rectal bleeding seriously, especially for individuals below the screening age.
In the United States, guidelines suggest routine colonoscopy screenings starting at age 45 for those without a family history of the disease. Conversely, the NHS offers bowel cancer screening tests to individuals aged 50 to 74.
The research, scheduled for presentation at the American College of Surgeons Clinical Congress 2025 in Chicago, aims to address the healthcare gap for symptomatic young adults who do not qualify for routine screening but are facing an increasing risk of colorectal cancer.
The study examined 443 patients under 50 who underwent colonoscopies between 2021 and 2023 at the University of Louisville Health System. Among them, 195 were diagnosed with early-onset colorectal cancer, while 248 had normal results.
Alarmingly, only one in 10 of the confirmed cancer cases had genetic markers or a family history of the disease. Those diagnosed with early-onset colorectal cancer were also notably more likely to be former smokers.
The research team is now commencing a larger study and aims to create a ‘risk score calculator’ to assist clinicians and patients in recognizing their risk beyond existing criteria such as family history.
Colorectal cancer, also referred to as bowel cancer, ranks as the fourth most common cancer in the UK, with a 53.9% survival rate for 10 years or more according to Cancer Research UK. However, the charity points out that 54% of cases are preventable.
The disease’s common causes include an imbalanced diet high in processed meat, alcohol, and smoking, with low fiber and physical activity levels. Being overweight or obese contributes to around 11% of cases in the UK.
Symptoms of colorectal cancer can encompass various signs such as rectal bleeding, changes in bowel habits, abdominal pain, and unexplained weight loss.