The clinical significance of antibody against oncofetal antigen-I (anti-OFA-I) in patients with gynecologic tumors

Oncofetal antigen-I (OFA-I) is a membrane antigen of human cancer cells that cross-reacts with human fetal brain tissues. The antibody profile against this antigen was analyzed in relation to the course of disease. Fifteen out of 22 patients had persistently stable antibody levels and antibody titer in three of them increased by more than 4-fold. These patients did not show either recurrence or death, but had a good prognosis. In four patients, antibody levels dropped by more than 4-fold and was followed by clinical recurrence and death. These studies show that persistently stable antibody titers are predictive of non-recurrence, and decreasing titers predictive of recurrence.