PIK3CA and Lynch syndrome: After limiting to studies that excluded Lynch syndrome, the associations between early-onset CRC and <i>BRAF</i> (0.77, 0.64-0.92) and <i>APC</i> mutation (0.81, 0.67-0.97) were attenuated, while an inverse association with <i>PIK3CA</i> mutation was also observed (0.88, 0.78-0.99).