Lectin histochemistry in a case of ulcerative colitis complicating rectal carcinoma

The large bowel from a patient with ulcerative colitis complicating a rectal carcinoma was histochemically investigated by using two lectins; Ulex europaeus agglutinin-I (UEA-I) and peanut lectin (PNA). Much UEA-I binding glycoantigen and PNA binding glycoantigen appeared in the carcinoma and dysplastic lesion whereas only a small amount of both antigens was found in the non-dysplastic regenerating epithelium. Consequently, a very sharp contrast between the dysplastic lesion and non-dysplastic regenerating epithelium was demonstrated by the lectin staining.