Detection by Immunofluorescence of Carcinoembryonic Antigen in Colonic Carcinoma, Other Malignant or Benign Tumours, and Non-Cancerous Tissues

Summary.-A 3-layer immunoperoxidase technique was used to demonstrate carcinoembryonic antigen (CEA) in colonic polyps from patients with or without previous or concurrent malignancy. CEA was demonstrated in a higher percentage of the polyps received as fresh specimens that were rapidly frozen and fixed in ethanol, than in formalin-fixed, paraffin-embedded sections. Tissue CEA content of both colonic carcinomas and polyps was determined by radioimmunoassay, and it was found that benign colonic tumours had levels of tissue CEA comparable to colonic cancer, indicating that CEA concentration in a tumour does not reflect its grade of malignancy. In fact, in one case in which both colonic cancer and polyps were removed, the polyps had the higher quantities of tissue CEA. Further, tissue CEA concentration of a polyp was not dependent on its size or location. Studying the titres of circulating CEA in these patients revealed an elevation of plasma CEA in one-third of the patients with only colonic polyps, whilst the patients with cancer all had increased titres.

Section: Discussionsupporting

confidence: 91%

Rauscher virus-induced reticulum-cell sarcomas: their growth in vitro and erythropoietic differentiation

Fieldsteel¹,

Dawson²,

Becker³

et al. 1977

“…Indeed, Lipkin and co-workers have described changes in the nucleic acid metabolism and proliferative capacity of the colonic epithelium in DMH treated mice (Thurnherr et al, 1973;Deschner, 1974) which are similar to those found in the human colonic mucosa adjacent to carcinoma and neoplastic polyps (Immondi, Balis and Lipkin, 1969;Deschner and Lipkin, 1970;Troncale, Hertz and Lipkin, 1971) and in familial polyposis (Lipkin, 1974). These changes may reflect a loss of suppressor genes and a regression of the cell to a more embryonic state, a hypothesis supported in the demonstration of embryonic specific antigens in malignant tumours (Gold and Freedman, 1965;von Kleist and Burtin, 1969;Stonehill and Bendich, 1970;von Kleist, 1971;Bordes, Michiels and Martin, 1973).…”

Section: Discussionsupporting

confidence: 56%

Mucous secretion in rat colonic mucosa during carcinogenesis induced by dimethylhydrazine. A morphological and histochemical study

Filipe¹

1975

178

Summary.-Our previous studies, in specimens of large intestine resected for carcinoma, have shown abnormal patterns of mucous secretion in areas of apparently " normal " mucosa, where goblet cells produce mainly sialomucins as compared with the true normal colonic mucosa in which sulphomucins predominate. In the present work, large bowel cancer was induced in rats by the administration of 1,2-dimethylhydrazine-2HCl (DMH). We attempted to study the sequential histological and secretory abnormalities which developed in the colonic epithelium during carcinogenesis, and to correlate these changes with those described above in the human. The microscopical and histological lesions observed in the colonic mucosa of DMH treated rats confirmed the findings of other authors and resembled the human colorectal cancer. The earliest changes detected were small foci of hyperplasia accompanied from the 6th week onwards by several foci of dysplasia. Carcinoma in situ appeared at the 15th week and finally invasive carcinoma developed from the 19th week onwards. Changes in the type of mucous secretion, with predominance of sialomucins, were observed in the majority of the areas showing mild to moderate dysplasia whilst the surrounding normal epithelium produced sulphated material. Mucous depletion was a common feature in areas of severe dysplasia and carcinoma.These findings correlated well with the similar variations in the mucin composition observed in human colonic mucosa in carcinoma and further supported our previous hypothesis that mucin changes characterized by an increase in sialomucins might reflect early malignant transformation. If this hypothesis proved to be correct, the use of a simple method for the identification of mucins in large bowel biopsies would be of great help in detecting early malignancy.

“…In some cells of MCT the immunofluorescence was seen around the cell surface, but was almost absent from the cytoplasm. The finding is quite similar to those shown in carcinoma or polyp of the colon, in which CEA is located on the luminal cell surface (Gold, Gold and Freedman, 1968; Kleist and Burtin, 1969;Denk et al, 1972;Burtin et al, , 1973Bordes, Michiels and Martin, 1973). In other cells, however, bright fluorescence was noted throughout the cytoplasm, exhibiting granulation.…”

Section: Discussionsupporting

confidence: 83%

Localization of carcinoembryonic antigen in medullary thyroid carcinoma by immunofluorescent techniques

Hamada¹

1977

Summary.-Cellular localization of carcinoembryonic antigen (CEA) in medullary thyroid carcinoma was studied in ethanol-fixed, paraffin-embedded specimens using the direct and indirect immunofluorescent techniques. It was demonstrated that CEA was present not only on the surface, but also in the cytoplasm of tumour cells. The immunofluorescence in the cytoplasm differed considerably in intensity from cell to cell. By contrast, no significant fluorescence was demonstrated in tissues of other types of thyroid adenocarcinoma, adenoma, Graves' disease and normal thyroid, with few exceptions. The results obtained indicate that CEA is actively produced by the tumour cells, and is present as a constituent of the cell membrane.