Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Since 1972 plasma CEA levels of 25 cancer patients have been assayed to evaluate the reliability of CEA as an early indicator of recurrent gastrointestinal cancer. Identification of significant elevations in CEA levels required definition of exactly what a given value meant. Intraassay and interassay accuracy was determined and graphed as a CEA NOMOGRAM, which measures the observed CEA level against the 95% confidence limits for that observation and thus can be used to identify statistically significant increases. A statistically significant rise above a baseline value established by the NOMOGRAM proved to be a correct indicator of tumor recurrence in 22 (88%) of 25 patients who underwent second-look intraabdominal operations (22 colorectal, 2 gastric, and 1 pancreatic). In each case, other accepted procedures, such as liver enzymes, scans, and x-rays, were nondiagnostic. Of the 22 patients with proved tumor recurrence, 16 (73%) had distant metastases and 6 (27%) had localized tumors. One patient remains tumor-free three years after second-look operation and has had no significant change in CEA levels. More frequent serial CEA determinations combined with sound clinical judgment should facilitate earlier detection of recurrent gastrointestinal cancer.
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PMID:The use of CEA as an early indicator for gastrointestinal tumor recurrence and second-look procedures. 83 30

Plasma CEA levels were evaluated by radioimmunoassay in patients with breast carcinoma in relation to clinical-pathologic staging, clinical tumor burden, prognosis and organ sites of involvement. Elevated levels were observed in 83/117 (70.9%) patients with metastatic disease, 2/14 preoperative patients and in 3/39 one-six month postoperative patients. Preoperative levels were elevated in two patients; the levels fell to normal after operation. Changes of elevated CEA levels followed the clinical response to therapy in 22/22 metastatic disease patient-trials. The levels decreased with a response in 15 trials and rose with progressive disease or relapse in seven trials. The incidence of CEA elevations and quantitative CEA levels both rose with increasing clinical tumor burden from the postoperative state through the preoperative state to two or more organ sites of metastatic involvement. No relationship was demonstrable among limited samples between preoperative or postoperative CEA levels and prognosis; however, in metastatic disease, pretherapy CEA levels greater than 5 ng/ml were associated with low response rates and early therapeutic failure to chemotherapy. The highest frequency of elevated CEA levels was observed in patients with osseous involvement (79%) and the lowest frequency with skin (52%) and breast (50%) metastases. Liver and osseous disease were also associated with higher mean CEA levels than were other sites of metastatic involvement. CEA levels appear to be elevated in the majority of patients with metastatic disease and be of prognostic importance in metastatic disease. The level in patients with metastatic disease appears to reflect the therapy-associated tumor burden of the host, especially in patients with elevated levels.
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PMID:Biological markers in breast carcinoma. III. Clinical correlations with carcinoembryonic antigen. 87 38

The altered growth characteristics of neoplastic cells have recently been associated with changes in membrane glycoproteins present on the cell surface. Since the carbohydrate moieties of surface membrane glycoproteins are asymmetrically located on the external cell surface, these glycoconjugates are likely candidates for providing cell surfaces with many of their biological properties. Using specific external cell surface labeling techniques, we have broadened our investigation of tumor cell surface glycoconjugates to include studies on cultured human epithelial cells from fetal intestine and from colonic carcinoma. We have isolated by affinity chromatography and gel filtration and integral membrane glycoprotein, termed Galactoprotein I, from a cultured human colonic adenocarcinoma cell line, which appears to be identical in many respects to CEA. Further examination of cell surface glycoproteins regarding quantitative and qualitative alterations and topographical redistribution should provide an insight into the biological aspects of tumor development.
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PMID:Biology of colon cancer: an overview. 92 88

161 patients with adenocarcinoma of the gastrointestinal tract were studied to determine the value of the CEA test and a battery of non-specific immunological tests during the course of the disease. The ability of these tests to detect a tumor recurrence in radically operated patients was evaluated. A false negative preoperative CEA value was found in 40% of the patients with gastric carcinoma and 32% with colorectal carcinoma. Patients with a negative preoperative CEA value, and those with only slightly elevated values, had a distinctly better prognosis regarding initial operability and tendency to postoperative recurrence than patients with primarily markedly elevated values. With few exceptions, the development of distant metastases was detected earlier and more easily with the CEA test than by the usual routine follow-up methods. However, in the event of isolated local recurrence the CEA test was positive in only 1 of 5 patients. This reflects the direct correlation between tumor size and CEA elevation. The CEA test is a valuable supplement in the follow-up of patients with gastrointestinal carcinoma.
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PMID:[The CEA test and other immunological tests as disease course controls in gastrointestinal adenocarcinoma]. 92 29

Serial CEA radioimmunoassays were performed on 16 patients receiving preoperative radiation therapy of rectal cancer or irradiation of recurrent or metastatic colorectal cancer. Radiation therapy of localized colorectal cancer reliably reduced previously elevated circulating CEA titers. Significant decrease of elevated CEA titers with accumulating doses of irradiation may indicate that the bulk of CEA-producing tumor is within the radiation treatment portal and assist in patient management decisions. The decrease of circulating CEA with preoperative radiation therapy was of short duration and may indicate that surgical resection should not be delayed more than 6-8 weeks after irradiation. Because of the high frequency of false positive and false negative results, CEA must be used only in conjunction with other clinical and laboratory parameters.
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PMID:Carcinoembryonic antigen (CEA) monitoring of radiation therapy for colorectal cancer. 97 May 37

Analysis of carcinoembryonic antigen (CE)-reactive glycoproteins from liver metastasis of primary colon and breast tumors and from primary breast tumors has been carried out by affinity chromatography on concanavalin A (Con A)-Sepharose. Three CEA-reactive glycoproteins from colon tumors (liver metastasis) with different binding capacity to Con A have been separated and further purified by gel filtration. Of the 3 CEA-reactive glycoproteins, 1 of them did not bind to Con A. Both Con A-binding and nonbinding CEA-reactive glycoproteins were immunologically indistinguishable when tested with a reference goat anti-CEA (ACE, 67-70; Dr. C.W. Todd and Dr. M.L. Egan), as well as with a variety of rabbit anti-CEA and anti-CEA (nonbinding) prepared in this laboratory. Carbohydrate analysis showed that mannose content of different purified CEA preparations or nonbinding CEA did not differ appreciably. N-Acetylglucosamine content of purified CEA preparations, however, varied considerably, suggesting that this sugar may impart the specificity of binding of CEA to Con A. The purified CEA preparations differed in their ability to inhibit the binding of 125l-labeled CEA to goat anti-CEA. One of the purified CEA preparations had 3- to 8-fold greater inhibitory capacity when compared to other preparations and shared a partial identity with a glycoprotein present in the extracts of fetal colon. The glycoprotein extracts of primary breast tumors did not contain a CEA that was immunologically identical to CEA present in colon tumors, whereas the liver metastasis of primary breast tumors showed several CEA-reactive glycoproteins as judged by radioimmunoassay. However, these CEA-reactive glycoproteins did not have any antigenic relationship with CEA from colon tumors when tested by double diffusion and immunoelectrophoresis. In conclusion, when Con A affinity chromatography of tumor glycoproteins is carried out under defined conditions and with the use of appropriate antisera, it is possible to delineate the presence or absence of CEA in tumors of nonentodermal origin.
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PMID:Immunochemical studies on carcinoembryonic antigen-reactive glycoproteins from carcinomas of the colon and breast separated by concanavalin A affinity chromatography. 97 8

Through persistent clinical research efforts, the CEA test has developed into a useful although complex disease monitor for colorectal cancer. Although improved or prolonged survival from its use has not been demonstrated, CEA monitoring may allow more knowledgeable patient management. Several reports indicate that postoperative serial CEA assays may identify patients with early recurrence, especially when assays are done frequently. Patients with elevated pretreatment CEA levels usually showed progressively rising titers before other objective evidence of recurrence was apparent. A progressively rising CEA titer correlated well with recurrent cancer, but a normal CEA could not be used as proof of its absence. Persistently elevated CEA titers post-treatment was caused either by persistent disease or by nontumor-related factors. The CEA assay was not a substitute for clinical follow-up but was an adjunct in the diagnosis of eary recurrence. Patients with elevated CEA levels caused by localized disease treated by radiation therapy demonstrated a marked fall in serial CEA levels if all CEA-producing tumor was localized within the radiation portal. The use of pretreatment CEA values plus the pattern of CEA reponse to irradiation may help in the selection of fulguration versus abdominoperineal resection as primary treatment for rectal cancer. Persistently low serial CEA titers after irradiation therapy correlated with disease control. The use of frequent serial CEA assays in patients treated with chemotherapy compared well with other parameters as a monitor of disease progression or regression. When used with other clinical parameters, serial CEA trends appeared to be a useful adjunct in assessing the effectiveness of chemotherapy. A fall in circulating CEA or the stabilization of a rising titer after starting chemotherapy usually indicated an effective regimen, whereas a rising CEA titer may signal may signal the need to initiate or to change chemotherapy.
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PMID:Patterns of serial CEA assays and their clinical use in management of colorectal cancer. 99 14

Other approaches to determine whether patients have a high probability of metastases (and therefore no need for axillary dissection) have been the measurements of several circulating substances (e.g., polyamines, nucleosides, CEA and HCG). None of these are by themselves useful. There is a high percentage positive in those patients with metastatic disease (with up to 97% positive for either HCG, CEA, or guanosine (nucleoside). What we need is a correlation or a parameter of what the tumor cell number is, who to treat, and how long. Today's therapy is larger empiric. The ultimate goal is to individualize therapy. Figure 1 summarizes a planned treatment for a woman with a breast cancer in 1974.
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PMID:Cancer treatment combined modality approach. 102 65

Binding of globulins to -125I CEA was detected in 10 of 24 sera from patients with cancer, 13 of 26 sera from blood donors, and 7 of 27 supernates of tumor-cell suspensions. Binding was predominantly by IgM in 10 of 14 sera tested by radioimmunoelectrophoresis. Binding was inhibited by 6 ng unlabelled CEA in one instance only, and by adsorption with blood group A erythrocytes in three cases. Binding was not increased in dialysed precipitates formed by ammonium sulfate at pH 2.5, while there was increased binding in precipitates of complexes of CEA and heterologous anti-CEA. These results confirm that human IgM binds to CEA, and in some cases binding appears to be mediated by antibodies to blood group A. However, the binding is weak and appears to be of low affinity. This suggests that binding of CEA by immunoglobulins represents cross-reactivity by antibodies to similar antigens, of which blood group A is one example.
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PMID:The antigenicity of carcinoembryonic antigen in man. 107 5

CEA is a beta1-glycoprotein (mol. w. approx. 200 000) which in embryonic life is usually found as a cell membrane associated antigen in the gastrointestinal (GI) tract and pancreas. Furthermore, it is secreted into body fluids. In healthy adults a very low serum concentration may be found. The clinical significance of CEA lies in its increased formation in primary and secondary adenocarcinomas of colon and rectum and pancreatic carcinoma, where values of 20 ng/ml and more are observed. However, other gastrointestinal (e.g. oesophagus, stomach, gall-bladder) and extragastrointestinal tumors (e.g. lung, breast, urogenital, prostatic, ovarial carcinomas) as well as non-malignant diseases mainly of the GI tract (e.g. hepatitis, cirrhosis, pancreatitis, colitis, diverticulitis) may provoke less frequent and lower increases in the CEA level. Healthy smokers also tend to show a slight increase in CEA concentration. A certain relationship exists between the CEA level and the size and extent of the tumor so that a decrease following operation may account for complete tumor removal, whereas a persistent or recurring increase in the CEA level is highly suspicious of metastases and/or recurrent tumor. Difficulties in proving and purifying CEA are mainly caused by multiple cross-reactions of CEA with other substances, e.g. blood group substances (A, B, Lea, Leb) and normal or other antigens (NGP, NCA, CEX, CCEA 2, NCA 2, CCA-III, FSA, BCGP). The radioimmunoassay is the most suitable method to determine CEA levels in body fluids. The 3 procedures used differ in the precipitation of the specific immune complex by ammonium sulphate (AS), Z-gel (ZG) or a second antibody (SA). Depending on the method, the upper normal limit in serum or plasma corresponds to approximately 2.5 (AS, ZG) or 12.5 (SA) nanogramme/milliliter. CEA determination in the urine is of interest in patients suffering from bladder carcinoma.
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PMID:[Carcinofetal antigens. II. Carcinoembryonic antigen (CEA). (author's transl)]. 108 Feb 18


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