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R Lamerz

Publications and source records attributed to R Lamerz.

At least 55 records · Page 3Linked to original sources
PubMed1991

[Circulating "tumor markers" in gastrointestinal tumors].

Tumor markers (TM) of the neoplastic cell can be divided into non-shedded substances and antigens shedded in blood, urine or other body fluids. For clinicians circulating TM are more important. All relevant circulating TM are not useful in screening of asymptomatic patients because of insufficient sensitivity and specificity. With caution they are useful in the observation of risk groups. Circulating TM have their main significance as additional parameters in monitoring symptomatic patients with malignancies. Several follow up determinations are more important than one single measurement. During follow up of tumor patients TM should not be checked automatically if there are no diagnostic or therapeutical consequences. The clinically most important circulating TM in non-hormone secreting tumors of the gastrointestinal tract are the oncofetal antigens CEA and AFP and antigens defined by monoclonal antibodies e. g. CA 19-9 and CA 72-4. AFP is the primary TM in hepatocellular carcinoma, often elevated in hepatoblastoma and always normal in cholangiocellular carcinoma. CEA is the TM of first choice in patients with colorectal carcinomas and liver metastasis. CA 19-9 is TM of first choice in pancreatic carcinoma and additionally of diagnostic value in cholangiocellular carcinoma and tumors of the bile ducts. In cancer of the stomach CA 19-9 and CEA are secondary TM in combination with CA 72-4 as primary TM. Care should be taken that slight and moderate elevations of TM can be observed in benign diseases of liver, pancreas and bowel.

Biomarkers, Tumor↗
PubMed1990

Diagnostic significance of carcinoembryonic antigen in the differential diagnosis of malignant mesothelioma.

The histologic and cytologic distinction of malignant mesothelioma from carcinomas metastatic to the pleura or peritoneum is often problematic. For this reason immunologic methods are being increasingly used as diagnostic adjuncts. This review summarizes 40 studies on the expression of carcinoembryonic antigen in mesotheliomas and in lung and other carcinomas involving the pleura or peritoneum. Carcinoembryonic antigen was identified immunohistochemically in 11% of mesotheliomas and in 84% of carcinomas examined and immunocytochemically (in serous effusions) in 4% and 58%, respectively. In serum and in pleural or ascitic fluid, significantly elevated levels of carcinoembryonic antigen are commonly associated with (lung) carcinomas but rarely with mesotheliomas. Thus, together with identification of the antigen in serum, pleural fluid, or ascitic fluid, immunohistochemical and immunocytochemical techniques for detecting carcinoembryonic antigen provide a valuable aid for distinguishing malignant mesothelioma from metastatic carcinomas.

Biomarkers, Tumor↗
PubMed1989

[Clinical relevance of tumor markers].

Tumour markers are often circulating tumour-associated indicators of tumour development. As such they are not suitable for tumour screening and localization, but valuable as adjuncts for medical follow-up care of tumour patients, where their serum level alterations may anticipate the clinical detection of tumour behaviour by a lead time of 1 to 6 months before other methods. The following tumour may be controlled by established markers: endocrine tumours by NSE, calcitonin, parathormone, 5-HIAA, catecholamines/metabolites etc.; head-neck tumours: SCC, CEA; thyroid carcinoma: TG, calcitonin; lung cancer: CEA, NSE, SCC; liver cancer: AFP (PLC), CA 19-9 (cholangiocell.), CEA (secondary): biliary tract and pancreatic cancer: CA 19-9; colorectal carcinoma: CEA, CA 19-9; squamous cell carcinoma (ENT, oesophagus, anal): SCC; breast cancer: CEA and CA 15-3; ovarian cancer: CA 125 (epithelial), CA 19-9 (mucinous); germ cell tumours (ovary including trophoblastic tumours/testes): AFP and HCG; prostatic cancer: PAP and PSA; bladder cancer: TPA.

Biomarkers, Tumor↗
PubMed1989

Epidermal growth factor receptors and epidermal growth factor-like activity in colorectal mucosa, adenomas and carcinomas.

The epidermal growth factor (EGF) and alpha-tumor growth factor are mitogenic proteins which bind to the EGF-receptor and may play a role in carcinogenesis or tumor progression. Our study investigated whether colorectal carcinomas and adenomas express altered levels of EGF-receptors or overproduce EGF-like activity by comparing histologically normal mucosa to carcinomas resected from the same patients. EGF-receptors were characterized by radioligand binding studies. Carcinomas contained unchanged or decreased levels of EGF-receptors in 13/16 and moderately increased levels in 3/16 patients as compared to normal mucosa. Adenomas obtained from 2 patients with familial polyposis coli and from a third patient with a coincident carcinoma had similar numbers of EGF-receptors as normal mucosa. EGF-like growth factors, in contrast, were significantly elevated in carcinoma extracts as compared to extracts from normal mucosa of the same patients. Adenomas did not contain elevated levels of EGF-like activity. We conclude that increased expression of EGF-receptors is infrequent in colonic adenocarcinomas. Increased production of EGF-like growth factors may frequently occur but seems to be associated with tumor progression rather than with premalignant lesions as represented by adenomas.

Adenomatous Polyposis Coli↗
PubMed1988

Tumour associated antigens in diagnosis of serous effusions.

The use of tumour associated antigens in the diagnosis of serous effusions was studied in 76 patients with benign and 200 patients with malignant disease. Tissue polypeptide antigen (TPA), alpha fetoprotein, and CA 125 were found to be of little value. At cut off points of 3 ng/ml, 10 U/ml, and 30 U/ml, respectively, carcinoembryonic antigen (CEA), biliary glycoprotein I (BGP I), and CA 19-9 discriminated between benign and malignant serous effusions with a sensitivity of between 24% and 67%. The immunocytochemical staining for these markers resulted in malignant cells being detected in 18% to 33% of cases. Various combinations of conventional cytological examination, effusion fluid tumour marker determination, and immunocytochemical analysis identified malignant cells in serous effusions in up to 72% of cases; conventional cytology alone detected tumour cells in only 30%.

Antigens, CD↗
PubMed1988

Elevated serum CA 125 levels in patients with benign ascitic or pleural effusions.

The tumor-associated antigen CA 125 is widely used in monitoring of ovarian carcinomas. As this determinant is also expressed in proliferating mesothelia, we studied CA 125 levels in serum and effusion fluid of patients with ascitic and pleural effusions. Patients with benign and malignant disease were included. There was no statistically significant or diagnostically useful difference between 26 benign and 44 malignant cases in the CA 125 levels in effusions or sera. In 77% of benign cases, serum levels exceeding 105 U/ml (3 times the recommended upper limit of normal values) were found. Thus, in patients with serous effusions, elevated serum CA 125 values alone do not provide evidence for the presence of an (ovarian) malignancy, but may also indicate a proliferation of mesothelium due to benign disease.

Adult↗
PubMed1987

[High Ca 125 serum level in benign ascites or pleural effusion].

In 26 patients with benign and 44 patients with malignant ascites or pleural effusion the levels of the tumour marker Ca 125 were determined in the effusion and in the serum. No significant differences between both groups were seen. Values exceeding the tenfold level of the upper standard limit were often found even in patients with benign and non-carcinomatous malignant diseases. This is probably due to a production of the antigen even in benign proliferating cells of the mesothelium. Enhanced Ca 125 serum levels cannot therefore be interpreted as indicating the presence of an (ovarian) carcinoma if there is an ascites or pleural effusion; they can also be an expression of a proliferation of the mesothelium in benign processes of other organs.

Adult↗
PubMed1986

[Tumor markers in the diagnosis of ascitic and pleural puncture fluids].

The identification of carcinoma cells in ascitic and pleural effusions by the detection of tumor markers was studied using an indirect immunoperoxidase method. Punctates from 56 patients with carcinomas, 18 with other malignant diseases and 10 with benign diseases were examined. In 35% of carcinomatous punctates tumor cells were stained by a CEA antiserum. No positive cells were found, however, in non-carcinomatous benign or malignant effusions. The immunocytochemical staining of CEA could detect tumor cells in 36% of carcinoma cases classified suspicious or negative using conventional cytology only. A TPA antiserum as well as the monoclonal antibody OC 125 stained cells in carcinomatous as well as in non-carcinomatous malignant and in benign punctates.

Adult↗
PubMed1983

Immunological comparison of carcinoembryonic antigen (CEA) extracted from tumours of various organs: their use in radioimmunological CEA determinations.

CEA was extracted by the perchloric acid method from primary adenocarcinomas of the colon and the ovary, from ascitic and pleural fluids from patients with pancreatic, lung and breast cancer, and from the cyst fluid of a benign ovarian cystadenoma. Further purification included gel filtration and affinity chromatography. Antisera against CEA from colon, breast, ovary, lung and pancreatic cancer were produced in rabbits. In double diffusion experiments, all these CEA samples showed a reaction of complete immunological identity with all the anti-CEA sera, whatever their origin. CEA from colon, breast, pancreas and ovary were labelled with 125I and used in radioimmunological experiments. In a radioimmunological system where the tracer and the antiserum were constant, all the CEA used as standards gave parallel inhibition curves, having nearly identical slopes. This was another criterion of immunological identity. Sera of numerous cancer patients were assayed in several RIA systems, one of them being the classical system with colonic CEA as tracer and anti-colonic CEA as antiserum, the others being "organ specific" systems. The values obtained in these assays were found to be highly correlated: the rank coefficient of correlation between colonic and breast cancer RIA systems was rs = 0.96, that between colonic and ovarian RIA systems, 0.92, that between colonic and pancreatic RIA systems, 0.97 and that between colonic and lung RIA systems 0.96. It is thus concluded that by use of different organ-derived CEA preparations and their corresponding polyclonal antisera, no significative differences in serum CEA levels may be expected. No evidence of organ specificity of serum CEA was found.

Carcinoembryonic Antigen↗
PubMed1982

Immunological comparison of ovarian and colonic CEA.

Ovarian and colonic CEA were compared immunologically by means of antisera prepared against each of them. CEAs of both origins were found identical by immunodiffusion methods. In radioimmunological experiments, slight differences were observed between some but not all ovarian CEAs and colonic CEAs and also between different preparations of colonic CEA: no organ specificity of ovarian CEA could be demonstrated. Finally, CEA level was measured in 41 sera of patients with ovarian carcinoma by two radioimmunoassays, one using colonic CEA as tracer and standard and anti-colonic CEA serum, the other using ovarian CEA and anti-ovarian CEA serum: the values given by the two assays were highly correlated (rs = 0.8107), meaning that an organ specific assay for ovarian CEA is not needed.

Animals↗
PubMed1980

Use of human chorionic gonadotropin and alpha-fetoprotein radioimmunoassays: specificity and apparent half-life determination after delivery and in patients with germ cell tumors.

The specificity of commercially available hCG and hCG-beta antibodies (anti-hCG-beta from N.I.A.M.D.D. (SB6), Serono (S), Biosigma (B), Union Carbide (UC) (I.R.E.) and anti-hCG from Union Carbide) were compared. Using 125I-hCG (CR 115), the crossreactivity with LH (LER 960) was 5.5% for SB6, 0.25% for S and 0.3% for B. In the homologous hCG system UC, crossreactivity was 0.06% with hCG-beta and 1.2% with LH, in the hCG-beta system UC, it was 2.2% with hCG and 0.01% with LH. Parallel standard curves for hCG, the 2nd I.R.P. hCG and hCG-beta were found exclusively with the 125I-hCG, anti-hCG-beta system S. Consequently accurate estimates of the total hCG or hCG-beta content in serum and standardization with the 2nd I.R.P. is possible. This system is the most useful for clinical purposes. The serum half-life of hCG was calculated in 10 pregnant women after delivery and was found to be 10 to 34 h. AFP half-life time, determined by the double antibody radioimmunoassay was 4.0 +/- 1.8 (+/- SD) days in pregnant women after delivery (n = 60) and 3.8 +/- 0.9 days in neonates during the first 16 days of life (n = 26). Altogether, apparent half-life determinations were carried out in 29 patients with nonseminomatous germ cell tumors. The results indicate that half-life determinations of hCG and AFP may have a predictive value with respect to the monitoring of therapy.

Antibody Specificity↗