Blood group substance, CEA, and lectins in ovarian tumors

The presence of the blood group substances A, B, AB, Lea, and Leb and of CEA was demonstrated by peroxidase-antiperoxidase or fluorescein immunohistochemistry in histological sections of normal ovarian tissue and ovarian tumors of varying differentiation. In surface cells of normal ovaries and of benign tumors, blood group substances (BGS) were found in patterns corresponding to the serum blood group type of the patients. BGS were localized exclusively at the apical border of normal cells. CEA was almost always absent. In borderline lesions the presence of BGS was reduced by approximately 13%. The polar differentiation was often lost, and the BGS were unevenly distributed in the cytoplasm. The percentage of CEA-specific staining increased from less than 5% in normal tissue and benign tumors to 15% in mucinous and 10% in serous borderline tumors. Malignant tumors contained altered distribution patterns of BGS and CEA. In contrast to normal ovarian epithelia, BGS positivity was diminished distinctly; the decrease was particularly evident for Leb presence by reduction from 75 to 10%. CEA was observed in nearly 50% of the carcinomas (more often in mucinous than in serous carcinomas). Our study revealed that expression of blood group antigens was related to benign lesions, whereas its loss was associated with a greater malignant potential. Inverse correlations were found for CEA. Thus, immunohistological determination of these marker substances may be applied to tumor prognosis.