Antigenicity of a fetal extract in the leucocyte migration-inhibition test.

: Leucocytes from patients with gastric or colorectal cancer as well as from normal subjects were tested by the leucocyte migration-inhibition test against 3 M KCl extracts of three whole fetuses and eight fetal gastrointestinal tract tissues. The incidence of pathologic results in patients with gastric and colorectal cancer was 26% (25/77) and 34% (25/74), respectively. The values were significantly higher than those of normal subjects (3%, 1/30). No significant difference in the migration index was found between whole fetal and fetal gastrointestinal tract extracts. The migration index did not depend on CEA concentration in these fetal extracts. These results show that leucocytes from patients with gastric or colorectal cancer were sensitized to antigenic substance(s) in the fetal extracts, and suggest that gastrointestinal cancer and fetal tissue may share some common antigens.