Risk factors for early-onset colorectal cancer: A retrospective analysis of 3,369 cases.

e15671 Background: Early-onset colorectal cancer (EOCRC), defined as colorectal cancer (CRC) diagnosed in individuals under the age of 50, has been increasing in incidence worldwide. Colorectal cancer is now the leading cause of cancer death in men younger than 50 years and the second leading cause in women younger than 50 years in the United States. [1] Understanding the risk factors associated with EOCRC is crucial for early detection and prevention. This retrospective study aims to identify and evaluate the demographic, lifestyle, and modifiable risk factors associated with EOCRC. Methods: We conducted a retrospective analysis of 3,369 patients diagnosed with colorectal cancer between 2005 and 2024. Data was collected from a single institution’s cancer registry and electronic health records. Inclusion criteria included individuals diagnosed with CRC via colonoscopy, imaging, and/or pathologic confirmation. Risk factors evaluated included family history of CRC, smoking, alcohol consumption, signs of metabolic syndrome (diabetes, obesity, and/or hypertension), insurance status, and race. Statistical analysis was performed using multivariable logistic regression to assess the associations between these risk factors and the likelihood of early onset CRC. Results: Of the 3,369 patients, 395 (11.7%) were diagnosed with EOCRC (mean age = 41.71) and 2974 (88.3%) had late onset CRC (mean age = 69.23). EOCRC predominantly affected the sigmoid, rectosigmoid, and rectum (53.4%). Among the identified risk factors, both EOCRC and late-onset CRC patients shared a similar probability (53.6% v 50.2%) of having a family history of cancer. Of patients with EOCRC, 43.0% were current or former smokers, versus late onset CRC, in which 49.2% were current or former smokers. There was no statistically significant difference in alcohol consumption between EOCRC and late-onset CRC. Among patients diagnosed with EOCRC, 16/395 (4.0%) were also diagnosed with diabetes, 37/395 (9.4%) were either obese or morbidly obese, and 61/395 (15.4%) had hypertension. Conclusions: Our study highlights several key risk factors for early-onset colorectal cancer, including family history of CRC, smoking, and metabolic syndrome. Modifiable factors such as smoking and obesity may offer potential for prevention in high-risk populations, particularly the Hispanic population.