Weighing the Odds: Body Mass Index and Recurrence-Free Survival in Early-Onset Colorectal Cancer

The study investigated the relationship between body mass index (BMI) and recurrence-free survival in patients with early-onset colorectal cancer (before age 50). The research included 1,459 patients, of which 159 had early-onset and 1,300 had average-onset cancer (age 50 and older). In early-onset patients, a U-shaped association between BMI and survival was found, with the lowest risk at BMI 27 and highest risk at BMI below 20 and above 30. In average-onset patients, BMI was not associated with survival. The results suggest that the so-called "obesity paradox" (where overweight correlates with better outcomes despite obesity being a risk factor) may be specific to early-onset colorectal cancer. The authors recommend future research incorporating biomarkers and more detailed measurements of body composition.