Carcinoembryonic antigen and CA19-9: Implications of quantitative marker measurement in tissues for prognosis of colorectal cancer

Measurement of tumor markers in serum of colorectal cancer patients after s urgery is a sensitive method in early diagnosis of systemic spread of tumor cells. Moreover. prognostic association of carcinoembryonic antigen (CEA) content in serum at the time of surgery is well known. However, fairly uncl ear is whether quantitative content of CEA and CA19-9 in cancer tissue and adjacent normal mucosa of colorectal cancer patients is correlated to progn osis. Concentrations of CEA and CA 19-9 were analyzed simultaneously in ser um, cancer tissue, and normal colonic mucosa of 41 colorectal cancer patien ts operated for cure. Follow-up data were available for up to 82 months (me dian, 47 months) after surgery. During the follow-up period, 20 patients ha d a tumor recurrence. and all these patients died of metastatic disease. Us ing the median concentration of CEA and CA19-9 in tissues as a cut-off. no difference in overall and disease-free survival was observed between patien ts with elevated or normal CEA or CA19-9 concentrations in tumor tissue. Ho wever. in adjacent histologically normal mucosa, elevated CEA content was a ssociated with significantly shorter overall survival (P =.0385) and diseas e-free survival (P =.0141) but not CA19-9 content. Despite the unknown biol ogical function of tumor markers in malignant disease, measurement of tumor -associated antigens in colorectal tissues can become an interesting progno stic marker.