A series of clinical parameters such as radiation dose, concomitant chemotherapy protocols [11, 12], pre-treatment serum carcinoembryonic antigen (CEA) level [13], interval between completion of neoCRT and surgery [14, 15], and complication of Diabetes Mellitus [16] has been used to predict tumor responsiveness to neoCRT. Here, CEACAM5 is linked to diabetes mellitus.