[Lectins in pulmonary adenocarcinomas]

A relatively specific binding of lectins to various glycids enabled authors to evaluate the exosecretion characteristic of lung carcinomas closer than by HE, investigation of mucins and immunohistochemical epithelial markers. The main subtypes of lung adenocarcinomas (usual of acinar, tubulopillary cubocellular or cylindrocellular, solid with mucus production), pseudosarcoma, large cell and undifferentiated carcinomas from 9 bioptical samples were therefore compared as to binding of 5 lectins with preferential affinity to glucose/mannose (CON A), acetylglucosamin (WGA) and acetylgalactosamin (PNA, RCA, HPA). All the subtypes of adenocarcinoma as well as undifferentiated carcinoma showed a strong binding of bean lectin (CON A) and a slighter binding of ricinus (RCA) and wheat germ (WGA) lectins. Binding of Helix pomatia lectin (HPA) was nearly parallel to that of CON A even in large cell carcinoma (without mucin positivity)-except in undifferentiated carcinoma (in HE reminding of squamous carcinoma but CK negative). Peanut lectin (PNA) binding correlated with the production of acid glycosaminglycans and its lacking might serve as an indirect sign of Clara cell origin in some cubocellular bronchioloalveolar carcinomas which was otherwise difficult to prove. Lections mostly did not bind to mucus vacuoles and cytoplasmic granulary positivities represented secretion granules; marginal membranous positivities represented glycocalyx or lipoproteinaceous layer released by Clara cells in accordance with the expression of EMA. In pseudosarcoma a gradual binding of CON A from sarcomatoid to epithelial areas allowed to evaluate their connection better than according to an expression of cytokreatin.