TPS and CA 19-9 measurements in the follow-up of patients with pancreatic cancer and chronic pancreatitis

The aim of this study was to assess the value of TPS and CA 19-9 in a long-term follow-up analysis of 11 patients with chronic pancreatitis (CP) and 15 patients with pancreatic cancer (PC). In all monitored patients with chronic pancreatitis the initial TPS level was below 200 U/L, whereas CA 19-9 was elevated in two of them. In one patient a dramatic increase in the TPS concentration (820 U/L) was measured at the last follow-up visit (after 8.6 months), which led to the detection of PC. In all patients with PC the preoperative TPS level exceeded 200 U/L, whereas CA 19-9 was elevated in only nine patients. After the Kausch-Whipple operation 11 patients showed no evidence of disease and in eight of these patients both TPS and CA 19-9 were within the reference range; however, in three patients liver metastases were detected after 8-24 months from the last tumor marker measurement. In four of the 15 patients both markers were elevated at the end of the follow-up period and distant metastases were clinically confirmed. Our results indicate that in patients with CP and PC undergoing long-term follow-up, TPS reflects the clinical status of patients more accurately than CA 19-9.     

Identification of blood-protein carriers of the CA 19-9 antigen and characterization of prevalence in pancreatic diseases

The current best serum marker for pancreatic cancer, CA 19-9, detects a carbohydrate antigen on multiple protein carriers. Better knowledge of the protein carriers of the CA 19-9 antigen in various disease states may lead to improved diagnostic tests. To identify proteins that carry the CA 19-9 antigen, we immunoprecipitated the CA 19-9 antigen from pooled sera and identified the associated proteins using MS. Among the high-confidence identifications, we confirmed the presence of the CA 19-9 antigen on Apolipoprotein B-100 by antibody arrays and Western blot and on kininogen, ARVCF, and Apolipoprotein E by antibody arrays. We characterized the frequency and levels of the CA 19-9 antigen on the four proteins across various patient groups (pancreatic cancer, pancreatitis, and healthy controls) using antibody arrays. Nearly, 10-25% of the subjects showed elevations of the antigen on each protein, but the elevations were not associated with disease state or total CA 19-9 levels. These results contribute to our knowledge of the carrier proteins of an important functional glycan and the rate at which the glycan is displayed. This work also demonstrates a strategy for using the complementary methods of MS and antibody microarrays to identify protein carriers of glycans and assess the diagnostic value of measuring glycans on individual proteins.     

Blood groups antigens distribution in pancreatic cancer. An immunohistochemical study

Distribution and immunolocalization of blood groups antigens ABO were investigated in pancreatic cancer with the use of immunoperoxidase method. In contrast to earlier investigations no correlation was found between histological differentiation of pancreatic cancers and maintenance of the blood groups antigens in tumor cells.     

AFP, CEA, CA 19-9 and TPA in hepatocellular carcinoma.

The present study is based on the assay of four markers (AFP, CEA, TPA, Ca 19-9) using IRMA methods in 36 normal subjects, 44 cirrhosis and 66 HCC patients. Parametric and non parametric tests were used to test differences and correlations. ROC curves and discriminant functions were also elaborated. Normal 95% "cut-off" was determined by the "boostrap" method yielding: CEA 3.4 ng/ml; Ca 19-9 55 U/ml; TPA 58U/l and AFP 5.2 ng/ml. In HCC patients the values of the four markers were, on average, significantly different from those of normal subjects. However, only AFP and TPA exhibited high diagnostic accuracy (90%) for detection of the tumor. Higher than normal mean values for all markers were, also observed in cirrhotic patients. Only AFP yielded effective discrimination between HCC and cirrhosis. The positive prediction for the presence of the tumor on cirrhotic ground was 95% for AFP values higher than 18.5 ng/ml, with a 78% negative predictive value with a 6 ng/ml threshold. Association of AFP with TPA showed only a marginal diagnostic improvement. Results were not improved at all by combining CEA and Ca 19-9 with AFP and/or TPA. In conclusion, AFP is and remains the best marker for HCC and the only one effective in discriminating of HCC from cirrhosis. TPA may be considered a valid alternative if cirrhosis is not present. CEA and Ca19-9 are of no use.     

The significance of CA19-9 tumor antigen in the serum of patients with carcinomas

The concentration of serum CA19-9TM in 101 patients with colorectal adenocarcinoma (CRC), and 109 patients with carcinomas of lung, breast, stomach and pancreas and hepatoma, and 40 normal healthy controls including an equal number of smokers and nonsmokers were determined by solid phase radioimmunoassay of CA19-9 assay kits (Centocor). Of the normal sera, only 1 out of 40 (2.5%) was over 37.6 U/ml. No significant difference of CA19-9 levels was found between smokers (14.4 +/- 9.0 U/ml) and non-smokers (16.0 +/- 10.2 U/ml) of normal control. In patients sera, the mean value of CA19-9 levels was significantly higher in patients with Dukes B (P less than 0.05) and in patients with Dukes C and D (P less than 0.001) than the normal healthy control (15.2 +/- 10.2 U/ml). Analysis of serum CEA concentrations has shown a similar result in patients with all Dukes staged CRC. The CA19-9 levels was also significantly elevated in patients with gastric carcinoma, lung carcinoma, hepatoma, and especially in patients with pancreatic carcinoma (P less than 0.0001). The levels of CA19-9 elevated in 50% (22/44) of patients with advanced CRC while the elevation was 8 of 43 (18.6%) patients with localized CRC. A comparison of CA19-9 and CEA assays showed no correlation (r = 0.125) between the two assays. Although the CA19-9 assay (26.4%) was less sensitive than the CEA assay (51.7%), the specificity of CA19-9 assay (97.5%) was better than that of CEA assay (87.5%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Tumor markers in pancreatic cancer: a comparative clinical study between CEA, CA 19-9 and CA 50

Seventy-eight patients were evaluated to ascertain the usefulness of markers CA 19-9 and CA 50 in diagnosing pancreatic cancer, using a less specific marker (CEA) as reference. Three groups were considered: a) 36 controls; b) 22 patients with benign obstructive jaundice; c) 20 patients with pancreatic cancer. Preoperative blood samples were obtained to ascertain CEA (E.I.A.), CA 19-9 (R.I.A.) and CA 50 (T.R.-F.I.A.). Serum concentrations of the various markers were significantly higher for patients with pancreatic cancer in comparison with the other groups, at cut-offs of 10 ng/ml (CEA), 100 ng/ml (CA 19-9) and 170 U/ml (CA 50). The sensitivity of CA 19-9 (94%) and CA 50 (88%) was much greater than that of CEA (30%). The specificity of the three markers in patients with pancreatic cancer, with respect to the control group, was 100% and this figure is reduced with respect to the group suffering from benign obstructive jaundice (CEA: 90%; CA 19-9: 88% and CA 50: 87%). Diagnostic results (sensitivity, specificity, positive predictive value (P.P.V.) and negative predictive value (N.P.V.] did not significantly increase with respect to CA 19-9 and CA 50 when considered individually. It is concluded that the serum concentrations of CA 19-9 and CA 50 showed high sensitivity and specificity as markers of pancreatic cancer with respect to the other groups, pointing towards clinical routine clinical use of both markers. In addition, a comparative study of the literature has been made and prospects for short-term development and concrete applications for early and reliable diagnosis have been highlighted.     

Diverse monoclonal antibodies against the CA 19-9 antigen show variation in binding specificity with consequences for clinical interpretation

The CA 19-9 antigen is currently the best individual marker for the detection of pancreatic cancer. In order to optimize the CA 19-9 assay and to develop approaches to further improve cancer detection, it is important to understand the specificity differences between CA 19-9 antibodies and the consequential affect on biomarker performance. Antibody arrays enabled multiplexed comparisons between five different CA 19-9 antibodies used in the analysis of plasma samples from pancreatic cancer patients and controls. Major differences were observed between antibodies in their detection of particular patient samples. Glycan array analysis revealed that certain antibodies were highly specific for the canonical CA 19-9 epitope, sialyl-Lewis A, while others bound sialyl-Lewis A in addition to a related structure called sialyl-Lewis C and modification with Nue5Gc. In a much larger patient cohort, we confirmed the binding of sialyl-Lewis C glycan by one of the antibodies and showed that the broader specificity led to the detection of an increased number of cancer patients without increasing detection of pancreatitis patient samples. This work demonstrates that variation between antibody specificity for cancer-associated glycans can have significant implications for biomarker performance and highlights the value of characterizing and detecting the range of glycan structures that are elevated in cancer.     

Enhanced discrimination of malignant from benign pancreatic disease by measuring the CA 19-9 antigen on specific protein carriers

The CA 19-9 assay detects a carbohydrate antigen on multiple protein carriers, some of which may be preferential carriers of the antigen in cancer. We tested the hypothesis that the measurement of the CA 19-9 antigen on individual proteins could improve performance over the standard CA 19-9 assay. We used antibody arrays to measure the levels of the CA 19-9 antigen on multiple proteins in serum or plasma samples from patients with pancreatic adenocarcinoma or pancreatitis. Sample sets from three different institutions were examined, comprising 531 individual samples. The measurement of the CA 19-9 antigen on any individual protein did not improve upon the performance of the standard CA 19-9 assay (82% sensitivity at 75% specificity for early-stage cancer), owing to diversity among patients in their CA 19-9 protein carriers. However, a subset of cancer patients with no elevation in the standard CA 19-9 assay showed elevations of the CA 19-9 antigen specifically on the proteins MUC5AC or MUC16 in all sample sets. By combining measurements of the standard CA 19-9 assay with detection of CA 19-9 on MUC5AC and MUC16, the sensitivity of cancer detection was improved relative to CA 19-9 alone in each sample set, achieving 67-80% sensitivity at 98% specificity. This finding demonstrates the value of measuring glycans on specific proteins for improving biomarker performance. Diagnostic tests with improved sensitivity for detecting pancreatic cancer could have important applications for improving the treatment and management of patients suffering from this disease.     

Roles of CA19-9 in pancreatic cancer: Biomarker,predictor and promoter

Carbohydrate antigen 19-9 (CA19-9) is the best validated biomarker and an indicator of aberrant glycosylation in pancreatic cancer. CA19-9 functions as a biomarker, predictor, and promoter in pancreatic cancer. As a biomarker, the sensitivity is approximately 80%, and the major challenges involve false positives in conditions of inflammation and nonpancreatic cancers and false negatives in Lewis-negative Individuals. Lewis antigen status should be determined when using CA19-9 as a biomarker. CA19-9 has screening potential when combined with symptoms and/or risk factors. As a predictor, CA19-9 could be used to assess stage, prognosis, resectability, recurrence, and therapeutic efficacy. Normal baseline levels of CA19-9 are associated with long-term survival. As a promoter, CA19-9 could be used to evaluate the biology of pancreatic cancer. CA19-9 can accelerate pancreatic cancer progression by glycosylating proteins, binding to E-selectin, strengthening angiogenesis, and mediating the immunological response. CA19-9 is an attractive therapeutic target for cancer, and strategies include therapeutic antibodies and vaccines, CA19-9-guided nanoparticles, and inhibition of CA19-9 biosynthesis.     

Conformational analysis of the tumor-associated carbohydrate antigen 19-9 and its Lea blood group antigen component as related to the specificity of monoclonal antibody CO19-9

A structural comparison between the synthetic, tumor-associated 19-9 tetrasaccharide, NeuAc alpha 2----3Gal beta 1----3GlcNAc(4----1 alpha Fuc)-O(CH2)8CO2CH3 and its Lea blood group antigen component, Gal beta 1----3GlcNAc(4----1 alpha Fuc)-O(CH2)8CO2CH3 was carried out by two-dimensional 1H NMR spectroscopy and hard-sphere energy calculations. Significant chemical shift differences between the two molecules were detected only for protons at or near the linkage site of NeuAc to the Lea trisaccharide core. Coupling constants for the ring protons of both molecules did not suggest major deviation from the 4C1 chair conformation for Gal and GlcNAc, the 1C4 conformation for Fuc, or the 2C5 conformation for NeuAc. Two-dimensional nuclear Overhauser enhancement experiments revealed through-space, inter-proton interactions that corresponded to some extent with those predicted by diffraction data and hard-sphere energy minimization programs for both saccharides. However, a significant number of interactions did not obey the distance dependence predicted from a rigid structure model. These data suggest that, while the average conformation of the 19-9 antigen's Lea core may be invariant to NeuAc alpha 2----3Gal linkage, the dynamics of the Lea trisaccharide are altered upon sialylation. Data also indicate that the terminal NeuAc linkage is more flexible than the inter-residue bonds of the core trisacharide. This analysis, in combination with the fact that the monoclonal anti-19-9 antibody CO 19-9 does not cross-react with the Lea antigen, provides evidence in favor of NeuAc as an epitope-creating unit involved directly at the antibody binding site. However, given the possible role of variable dynamics in epitope formation, these results do not preclude crucial roles in antibody recognition for regions on the 19-9 antigen that are distanced from NeuAc.     

CA19-9 capability as predictor of pancreatic cancer resectability in a Spanish cohort

Molecular Biology Reports - CA19-9 serum has been suggested as a marker of unresectability but different cut-off levels have been published. A cut-off of 500 U/ml is currently considered in an...     

Value of CA 19-9 assay in serum and duodenal juice in the differential diagnosis of pancreatic disease

Levels of CA 19-9 in the serum and duodenal juice of nine patients with pancreatic adenocarcinoma (PC), ten patients with chronic calcifying pancreatitis (CCP) and ten healthy volunteers (C) were determined by immunoassay. Duodenal juice was obtained by duodenal intubation during the secretin caerulein test. Elevated CA 19-9 levels in the serum were significantly more frequent in PC than in CCP patients, but two PC patients gave levels only slightly above the cut-off value of 37 U/ml. CA 19-9 levels in duodenal juice were significantly higher in PC than in CCP patient, but there was some overlap between them; no overlapping was seen between PC or CCP group and controls. Two PC patients with duodenal juice CA 19-9 levels overlapping those of CCP were the same who showed only a slight rise in serum CA 19-9 levels. The CA 19-9 to total protein ratio in duodenal juice did not permit better discrimination between PC and CCP. We conclude that CA 19-9 assay in duodenal juice can differentiate healthy subjects from patients with pancreatic diseases, but it cannot improve the differential diagnosis between CCP and PC patients with a slight rise of CA 19-9 levels in serum.     

Establishment and characterization of human pancreatic adenocarcinoma cell line SOJ producing carcinoembryonic antigen and carbohydrate antigen 19-9

A new tumor cell line derived from a human pancreatic exocrine adenocarcinoma was established in tissue culture and was transplantable in a nude mouse. In tissue culture, the neoplastic cells grew as epithelial-like, mucin-producing cells with a population doubling time of 50-70 hrs. Chromosomes ranged from 63 to 186 with a modal number of 77. Subcutaneous injection of 1 x 10(6) cultured neoplastic cells into nude mice resulted in tumor formation histologically closely resembling the original neoplasm. Ultrastructurally, the cell line showed characteristic ductal epithelium. Immunohistochemically, carcinoembryonic antigen (CEA). Carbohydrate Antigen 19-9 (CA19-9) and DU-PAN-2 antigen were demonstrated in the original tumor, the culture cells and the transplanted tumor. The cells secreted CEA (48.7 ng/1 x 10(5) cells/24 hrs) and CA19-9 (325 U/1 x 10(5) cells/24 hrs) in spent medium as well as sera of the nude mouse. This cell line has been passaged 30 times in vitro and maintained for more than one year. These characteristics will make the cell line SOJ a valuable tool in studying various aspects of biology of human pancreatic cancer.     

The clinical value of the tumor markers CA 19/9 and carcinoembryonic antigen (CEA) in colorectal carcinomas: a critical comparison

The monoclonal antibody serum test CA 19.9 after having been described as being colon tumor specific, was advertised as being more sensitive than CEA in the detection of both early and advanced colorectal carcinomas. Furthermore, the combined estimation of the two markers, CEA and CA 19.9 was said to improve the detection rate significantly. However, our own comparative studies as well as those of several other groups recently published have shown CA 19.9 measurements to be less valuable, because being less sensitive than those of CEA. This is especially true for the early stages of intestinal carcinomas. The parallel determinations of CA 19.9 and CEA improved the positivity rate insignificantly, because in only 3.5% of all cases C 19.9 was elevated in CEA negative cancer sera. However, CA 19.9 was found to have a much lower rate of (false) positive results than CEA in benign intestinal diseases.     

Detection by monoclonal antibody of carbohydrate antigen CA 50 in serum of patients with carcinoma.

A solid phase radioimmunoassay was devised for measuring the value of the carcinoma associated carbohydrate antigen CA 50 in serum based on the use of a specific monoclonal antibody (C 50). Samples of serum from 259 patients with carcinoma, 114 patients with other malignancies or inflammatory diseases, and 150 healthy controls were examined. Serum values of CA 50 exceeding the mean plus three standard deviations for control samples from blood donors were found in a high proportion of patients with colorectal adenocarcinomas (50% of those with early, localised tumours and 75% of advanced cases), other gastrointestinal carcinomas (69%), uterine cancer (75% of those with corporeal and 88% of those with cervical cancer), prostatic cancer (90%), lung cancer (52%), and breast, ovarian, kidney, and urinary bladder carcinoma (26-67%). The CA 50 values in samples from patients with inflammatory diseases, including ulcerative colitis, with rare exceptions (0-7%) were within the normal range, as were those in patients with various sarcomas and malignant melanoma. Measuring serum values of CA 50, which is evidently a generalised carcinoma associated antigen, may be useful in clinical research studies of the diagnosis, management, and prognosis of patients with different types of carcinoma.     

Tumor markers (CEA, TPA and CA 19-9) in urine of bladder cancer patients

This study was carried out to evaluate the usefulness of determining urinary levels of carcinoembryogenic antigen (CEA), tissue-polypeptide antigen (TPA), and gastro-intestinal cancer antigen (Ca19-9) in addition to the usual diagnostic procedures for bladder cancer. Sixty-seven patients with transitional bladder cancer, 40 healthy controls and 20 patients with inflammatory diseases of the urinary tract were considered. All urine samples were obtained from patients with intact renal function and no urinary tract infection. TPA and Ca19-9 urinary levels in patients with G3 bladder tumors were significantly higher than in those with lower graded neoplasms. The sensitivity, specificity, and predictive value of a positive (PV+) or negative (PV-) test and the diagnostic accuracy were also evaluated. Ca19-9 was the best urinary marker for bladder cancer (sensitivity 71.6%, specificity 91.6%, PV+ 90.5%, PV- 74.3%, diagnostic accuracy 81%).