Prognostic Role of Pre-Treatment Carcinoembryonic Antigen and Carbonhydrate Antigen 19-9 in Metastatic Colorectal Cancer

Abstract

Objectives: Carcinoembrionic Antigen (CEA) and carbohydrateantigen 19-9 (CA 19-9) are the most commonly usedtumor-associated antigens in the colorectal cancer. Several contradictory studies reported that patients with metastatic colorectal cancer (mCRC) with normal serum CEA and CA 19-9 levels survived significantly longer than patientswith higher serum CEA and CA19-9 levels.Methods: 240 patients with mCRC were enrolled. The parameters evaluated were age, gender, tumor location, metastatic organs, resection of the primary tumor, metastasectomy, pretreatment serum concentrations of CEA and CA19-9,first line chemotherapy regimens and overall survival (OS). CEA and CA19-9 were divided into three groups as normal(CEA ≤5 ng/mL, CA 19-9 ≤35 U/mL) elavated (CEA: 5–50 ng/mL, CA19-9:35–350 U/mL) and high (CEA >50 ng/mL, andCA 19-9 >350 U/mL). Primary study endpoint was overall survival (OS).Results: Serum CA 19-9 level (p=0.040), primary tumor resection (p