Abstract
The expression of a novel tumour associated antigen CA 242, defined by the monoclonal antibody C 242, was studied by immunoperoxidase staining in formalin-fixed, paraffin-embedded tissue sections from normal pancreata, pancreata with pancreatitis and benign and malignant pancreatic neoplasms. The antigenic determinant of the C 242 antibody is a sialylated carbohydrate structure, related but chemically different from tumour marker antigens CA 19-9 and CA 50. Thirty-eight of 41 (93%) well to moderately differentiated ductal adenocarcinomas of the pancreas and all cystadenocarcinomas were positive for CA 242. The staining was most intense in the apical border of the cells, and in the intraluminal mucus. Only two out of seven poorly differentiated adenocarcinomas stained, and the number of positive cells was smaller than in well differentiated carcinomas. Only occasional cells were stained in one out of five anaplastic carcinomas. Part of large ducts were positive in 91% (21/23) specimens of chronic pancreatitis. In acute pancreatitis small terminal ducts, centro-acinar cells and some large ducts stained for CA 242. In normal pancreas only a few small terminal ducts were CA 242 positive. Carcinomas always stained more strongly for CA 242 than normal pancreatic tissue adjacent to the carcinoma. The results of CA 242 are compared with those of tumour marker antigens CA 50 and CA 19-9. Serum CA 242 levels were determined in 23 of the patients with pancreatic cancer using a fluoroimmunoassay. Fifteen (65%) patients had an elevated value. There was no clear-cut correlation between the serum levels and the immunohistochemical expression of the CA 242 antigen. The expression of CA 242 in pancreatic tissue resembles that of CA 50 and is similar to CA 19-9. The antigen is expressed in serum of many patients with pancreatic cancer and, therefore, is a potential candidate for a serum tumour marker.
Highlights
We have reported the immunohistochemical expression of the CA 19-9 and CA 50 antigens in pancreatic tumours, in normal pancreatic tissue and in pancreatitis (Haglund et al, 1986a, b)
Sections stained with nonimmune mouse serum and phosphate-buffered saline (PBS), respectively, instead of the primary antibody served as negative controls
An arbitrary scoring of distribution using + or + + was used. Specimens including both carcinoma and normal pancreatic tissue were used for comparisons between staining intensity of cancerous and normal tissue
Summary
Specimens studied were the following: 20 samples of normal pancreatic tissue (15 of which were resection surfaces from pancreata with cancer or chronic pancreatitis); acute and chronic pancreatitis tissue samples; 48 ductal adenocar-. Received 27 February 1989; and in revised form 23 June 1989. Cinomas (38 primary tumours and 10 metastatic tumours); five anaplastic carcinomas, seven cystadenomas, three cystadenocarcinomas and nine neoplasms of endocrine origin. The samples were formalin-fixed, paraffin-embedded surgical specimens, which had been stored for between 6 months and 10 years. Tissue culture supernatant containing mouse monoclonal antibody C 242 (IgGi) (Lindholm et al, 1985) was used for the CA 242 stainings. The optimal dilutions of primary antibodies were determined in control series
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
