Altered H-antigen reactivity as an early indicator of malignant transformation in oral epithelium.

This study was undertaken to determine whether or not the blood group H-antigen reactivity of oral epithelium has value in predicting malignant transformation. Tissue from 3 groups of patients was studied retrospectively, using an immunoperoxidase technique. Two biopsy specimens from each patient, obtained at different times but from the same site, were examined for the presence of H-antigen. Group I consisted of 16 patients in which the initial biopsy was histologically benign, but the subsequent biopsy revealed epidermoid carcinoma. The initial biopsies in Groups II (17 patients) and III (17 patients) revealed epithelial dysplasia. Whereas the subsequent biopsy in Group II revealed carcinoma, the subsequent biopsy in Group III remained non-invasive. Normal epithelium from 64 patients was also studied. The results showed that in normal epithelium, H-antigen-negative cells are rarely seen, but 81% of the initial benign specimens of Group I showed antigen-negative areas. Therefore, it was concluded that altered H-antigen reactivity in histologically benign epithelium may serve to predict eventual malignant transformation, and that immunologic dedifferentiation precedes histologic dedifferentiation. A comparison between the initial biopsy specimens of Groups II and III yielded nearly identical results and showed that it was not possible, on the basis of the H-antigen reactivity, to predict which dysplastic lesions would progress to epidermoid carcinoma.