Raised Carcinoembryonic Antigen (CEA) in Blood-Causes

Biochemical assays for tumour-associated enzymes, hormones and other tumour markers in the blood are not diagnostic but help in determining the effectiveness of therapy.
Carcinoembryonic antigen (CEA) is considered as tumour markers and is raised in the various tumour but it is also raised in various other benign conditions. Therefore, the Raised concentration of CEA in the blood is not a hallmark of Cancer.
Causes of the high level of Carcinoembryonic antigen in Blood:

1) Malignant tumours:
a) Breast cancer
b) Colorectal carcinoma.
c) Gastric cancer
d) Pancreatic cancer

2. Benign conditions
a) Hepatitis
b) Alcoholic cirrhosis of the liver
d) Crohn's disease
e) Ulcerative colitis
f) Healthy smokers