Differential expression of the cancer-associated antigens T (Thomsen-Friedenreich) and Tn in primary and recurring squamous cell carcinomas of the skin

The T (Thomsen-Friedenreich) antigen and its precursor the Tn antigen, are complex mucin-type carbohydrate antigens, the expression of which seems to be correlated with prognosis in some human cancers. We studied comparativel y the immunohistochemical expression of these antigens in a series of prima ry and locally recurring squamous cell carcinomas developing in the skin of immunosuppressed (organ-transplanted) patients. 10/26 tumours were complet ely unreactive for both antigens; among the remaining cases, 10/14 (71%) of recurring and 6/12 (50%) of primary tumonrs showed a higher expression of the precursor (Tn antigen) as compared with the T antigen. Since recurring tumours are more likely to spread metastatically, our results upheld the co ntention that a higher expression of the Tn antigen is correlated with a mo re aggressive course of cutaneous squamous cell carcinomas.