APC and colorectal carcinoma: In an effort to understand the different modes of pathogenesis in early-onset CRC, colorectal tumors from EOCRC (<50 years old) and Late-Onset patients (LOCRC; >50 years old) were screened to eliminate microsatellite instability (MSI), nuclear β-catenin, and APC mutations, as these are known canonical factors in CRC pathogenesis.