Obesity and gastrointestinal cancer: A converging epidemic with surgical consequence

Obesity is now a recognised carcinogen with growing implications for gastrointestinal surgical oncology. Excess adiposity promotes tumourigenesis through endocrine, inflammatory, and mechanical pathways, contributing to increased cancer incidence, stage at diagnosis, and worse oncological outcomes. For patients undergoing gastrointestinal cancer surgery, obesity adds significant technical complexity and elevates perioperative morbidity. While effective interventions such as bariatric surgery and GLP-1 receptor agonists now exist, their integration into cancer care remains limited. Emerging evidence suggests potential oncological benefit, but high-quality data on perioperative implementation and impact on treatment response are scarce. Randomised trials evaluating short-course pharmacological strategies during neoadjuvant pathways are urgently needed. In the interim, routine preoperative obesity screening and referral for structured weight loss should be embedded into multidisciplinary workflows. This perspective underscores the importance of recognising and addressing obesity not only as a comorbidity, but as a modifiable risk factor and therapeutic target across the cancer continuum.