CLINICAL INTEREST OF HYDROPHOBIC FORMS OF SERUM CARCINOEMBRYONIC ANTIGEN (CEA) MEASUREMENT IN METASTATIC COLON-CANCER

Thirty-four patients with metastatic colon cancer were treated with fl uorouracile and folinic acid. The follow-up of disease was evaluated b y tomodensitometric CT-scan analysis and by serum CEA determination. I n addition, a study of the different CEA molecular forms separated by Triton X114 partitioning immunoprecipitation and immunoblotting was co mpleted Concerning the aqueous phase, no relationship appeared between the pattern of CEA species and the outcome of chemotherapy. Opposingl y, the analysis of the hydrophobic phase gave results closely correlat ed to chemotherapeutic response. In 19/34 patients, the hydrophobic CE A forms were absent or weakly expressed; out of these patients, 16/19 underwent a successful response to chemotherapy regimen. Opposingly al l of the remaining 15 patients expressing high levels of hydrophobic C EA species were non-responders The present study thus gives new means for predicting the outcome of 5 fluorouracile-folinic acid chemotherap y by screening the molecular CEA forms expressed in the serum of patie nts with metastatic colon cancer.