EXPRESS: Early Onset Colorectal Cancer, not just the Age: data from a large health organization.

Early onset colorectal cancer (EO-CRC) is increasing. We investigated the risk factors for ER-CRC compared to late onset CRC (LO-CRC). CRC patients between the years 1999 and 2021 were retrospectively evaluated. Data regarding demographics, comorbidities, malignancies, and mortality were collected. Data were retrieved using the MdClone platform from a large Health Maintenance Organization. The cohort was subdivided into EO-CRC (age ≤50 years) and LO-CRC (age ≥51 years) groups. 61,679 patients diagnosed with CRC were included in our analysis, 30,456 (49.4%) males, and 4,891 (7.9%) Arabs, with an average age at diagnosis of 70.1±13.1 years. 5561 (9%) patients were included in the EO-CRC group. Over the last decades, higher rates of EO-CRC were diagnosed compared to the previous decade, 9.8% vs 8.3%, p<0.001. A higher percentage of EO-CRC patients were females (52.8% vs 50.4%), had a family history of CRC (9.9% vs 5.5%), were Arabs (18.7% vs 6.9%), and were smokers (32.7% vs 30.2%) compared to LO-CRC patients. Significantly lower rates of comorbidities such as ischemic heart disease, diabetes mellitus, hypertension, obesity, and iron deficiency anemia were found among EO-CRC patients, with a lower all-cause mortality (27.7% vs 63.1%, p<0.001). 348 (6.3%) of the EO-CRC patients had another Lynch-related cancer until age 50 years compared to 45 (0.1%) at the LO-CRC. Young individuals with increased risk for CRC need special consideration and should be referred early for screening and endoscopic investigation, particularly those with a family history of CRC, smokers, and those of Arab ethnicity.