When we analyzed the CEA level decline associated with tumor response specifically in patients with non-adenocarcinoma, we found that patients with a reduction of ≥14%, had an overall response of 66.7%, stable disease 16.7%, and progression 16.7%, compared to the non-adenocarcinoma patients who did not achieved a reduction of ≥14% with a tumor response of 9.1%, 59.1% and 31.8%, respectively (p = 0.009). Here, CEACAM5 is linked to neoplasm.