Early-Onset Colorectal Cancer.

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the United States, and the incidence of early-onset CRC (EOCRC, <50 years old) has been steadily increasing over the past 30 years. This article provides a comprehensive review of EOCRC traits, including incidence rates and patterns, tumor biologic differences compared to late-onset CRC, dietary risk factors, relationship between CRC and the microbiome, and patient survival outcomes associated with EOCRC. These factors carry importance in determining diagnostic, prognostic, disease monitoring, and treatment planning practices for EOCRC in the future. They also serve as guides for optimizing CRC screening recommendations.