Few studies have reported some conflicting result of clinical predictive factors for pCR, including tumor size,[13] tumor size from calculation by volumetry method,[14] nodal stage,[15] and pretreatment carcinoembryonic antigen (CEA) level.[16] Tumor length, as measured by computerized tomography scan or magnetic resonance imaging, is one of the routine clinical parameters collected in management of rectal cancer. Here, CEACAM5 is linked to neoplasm.