bromochloroacetic-acid and Intestinal-Polyps

1. CEA, a well established marker for benign and malignant colonic tumors is widely used for tissue staining and body fluid measurement. Highly specific monoclonal antibodies are now available. It is likely that CEA gene(s) will be available soon. 2. Monoclonal antibodies to blood group precursor antigens, especially extended LeX and LeY are also available and are known to detect premalignant lesions. 3. The demonstration that LeY is expressed in purified CEA specimens suggests a complementary relationship between the two markers of possible clinical utility. 4. Systematic comparison of both families of marker is timely. 5. Experienced pathologists have classified and standardized the histology of adenomatous polyps and their premalignant counterparts. The use of serial sections of identical tissues will permit comparison of several candidate markers in the same lesion. Selection of lesions which contain benign, malignant, and invasive components in the same section will provide best control, minimizing the need for exhaustive studies. 6. Laminin staining gives useful indication of early invasion through the basement membrane. It will complement morphologic and marker evidence for early malignancy and invasion. 7. It is unnecessary to investigate all polyps. Focus should be on high risk patients with (1) large polyps, severe dysplasia and advanced villous change, (2) synchronous polyps and invasive cancer, and (3) familial and other multiple polyposis disorders. 8. A plethora of other candidate markers is available, only a few of which are mentioned.

Topics: Antibodies, Monoclonal; Biomarkers, Tumor; Carcinoembryonic Antigen; Cell Line; Colonic Neoplasms; Humans; Immunohistochemistry; Intestinal Polyps; Keratins; Lewis Blood Group Antigens; Neoplasm Invasiveness; Precancerous Conditions

Double-label immunofluorescence was used to monitor basement-membrane composition and integrity in 22 human colon polyps, 36 adenocarcinomas and 2 metastases. Cryostat sections were stained with polyclonal anti-laminin anti-serum combined with monoclonal antibodies (MAbs) to all major basement-membrane components (laminin, entactin/nidogen, collagen type IV and large heparan sulfate proteoglycan), as well as to keratin 8. In all adenocarcinomas, including mucinous, basement membranes were altered more at the invasive front than in the parenchyma. The degree of this alteration was inversely correlated with the level of tumor differentiation. An uncoordinated loss of basement membrane components (dissociation of markers), previously described by us in rat colon adenocarcinomas, was also found in human tumors. In the great majority of adenocarcinomas a pronounced stromal reaction was seen. It was manifested by the presence of fibrillar deposits of basement-membrane components, mainly of collagen type IV and/or heparan sulfate proteoglycan. This reaction was never observed in polyps and may be derived from myofibroblasts reported to accumulate in colon cancer stroma. The combined use of antibodies to basement-membrane components and to a specific keratin may constitute an adequate immunohistochemical test for the presence of invasion, and may be useful in the histologic analysis of polyps, especially in dubious cases.

Topics: Adenocarcinoma; Antibodies, Monoclonal; Basement Membrane; Blotting, Western; Collagen; Colon; Extracellular Matrix Proteins; Fluorescent Antibody Technique; Heparan Sulfate Proteoglycans; Heparitin Sulfate; Humans; Intestinal Neoplasms; Intestinal Polyps; Keratins; Laminin; Lymphatic Metastasis; Membrane Glycoproteins; Proteoglycans

Five thousand seven hundred seventy-eight adenomas or adenomas containing carcinoma from 3215 patients were examined by routine histologic methods for the presence of epithelial metaplasias. Three forms of epithelial metaplasia were encountered: squamous cell metaplasia (0.44%), Paneth cell metaplasia (0.20%), and melanocytic metaplasia (0.017%). In several instances multiple forms of metaplasia were encountered in the same polyp. In those cases in which the paraffin blocks were available, a Grimelius stain was performed. Grimelius-positive cells were present in 63% of the adenomas containing a metaplastic cell type. All cases with Paneth cell differentiation were immunoreactive for lysozyme; all lesions containing areas of squamous differentiation were immunoreactive for keratin except 2. The histopathologic features of these cases are discussed, and it is concluded that rather than representing a true metaplastic process, Paneth cell, squamous cell, and melanocyte differentiation represent the full range of cellular differentiation that endodermally derived tissues can exhibit, particularly when they undergo neoplastic alterations.

Topics: Adenoma; Adult; Age Factors; Aged; Cell Differentiation; Colonic Neoplasms; Female; Histocytochemistry; Humans; Intestinal Polyps; Intestine, Large; Keratins; Male; Melanocytes; Metaplasia; Middle Aged; Muramidase; Rectal Neoplasms; Retrospective Studies; Sex Factors