CEACAM5 and colorectal carcinoma: It has been proposed that exosomal microRNAs can achieve high specificity and sensitivity of up to 95% for miR-1229 while the sensitivities of CA19-9 and CEA for stage I CRC are only 10 and 15% respectively, suggesting the potential of exosomal microRNAs as novel biomarkers in diagnosing CRC even at early stages.