Early-Onset Digestive System Cancers: Risk Factors and Clinicopathological and Molecular Features Across Organ Sites

The incidence of early-onset cancers, commonly defined as cancers diagnosed before age 50 years, has been increasing globally over recent decades. In particular, the incidence of several early-onset digestive system cancers, including cancers of the esophagus, stomach, colorectum, liver, extrahepatic bile duct, gallbladder, and pancreas, has been reported to be increasing in multiple regions. To elucidate carcinogenic mechanisms and develop effective prevention, earlier detection, and treatment strategies, further evidence is needed on risk factors and clinical, pathological, and molecular characteristics. In this review, we summarize the current evidence on these characteristics, highlight shared and distinct features across organ sites, and discuss research opportunities to address the rising burden of early-onset digestive system cancers.