Expression of carbohydrate antigens in human pulmonary adenocarcinoma

The altered and anomalous expression of carbohydrate antigens (CA) occur in patients with lung carcinomas.

To investigate the relationship between prognosis and immunohistochemical findings of CA in serum and pulmonary adenocarcinomas (PA), PA specimens surgically resected from 102 patients were studied with the use of A, B, H, Lewis(Le)a, Le(b), Le(x), Le(y), sialyl Le(a) (FH-7), sialyl Le(x-i) (SLX) (FH-6), sialosyl Tn (TKH-2), and CA 19-9. The Lewis blood group types were determined by the dot blotting method on patients' serum using monoclonal anti-Le(a), Le(b), Le(x), and Le(y). Formalin-fixed paraffin-embedded PA sections were stained using the avidin-biotin-peroxidase complex methods.

There was no correlation between the patients' postoperative survival and tissue expression of CA, although survival correlated with the clinical stages, histologic differentiation of PA, and serum SLX in Stage 4. The higher the positive rate of both Le(b) and Le(y), the better their differentiation in PA specimens. Regardless of blood group type, PA showed high positive reactions for FH-6 (88%) and Le(y) (87%). The serum concentration of CA 19-9 correlated with immunohistochemical reactions of tumors (Spearman correlation coefficient = 0.33, P = 0.02). The expression of Le(a) in Lewis (a-b+) phenotype patients and Type 2 CA, such as Le(y) and FH-6, is characteristic in PA.

The findings suggest that CA tissue expression may not reflect postoperative survival length of patients with PA, but biological aberrant fucosylation or sialylation as well as morphologic alteration may occur in neoplastic cells.