Serum levels of cancer-associated antigen CA-195 in gastrointestinal cancers and its comparison with CA19-9

Preoperative Carbohydrate Antigen 195 (CA195) and CEA Serum Levels as Prognostic Factors in Patients with Colorectal Cancer

We evaluated in 214 patients with primary colorectal cancer the prognostic value of the preoperative serum levels of CEA and CA195. For CEA these levels were above the cutoff of 6 ng/ml in 31.3% of patients, whereas for CA195 they were higher than 12 U/ml in 35.9% of patients. The simultaneous use of both antigens increased the sensitivity to 49%, which was significantly higher than that of CEA (p<0.001) and CA195 (p<0.01) taken singly. The mean preoperative CEA levels were significantly (p<0.001) correlated with Dukes’ stage only, while there was a significant correlation between preoperative serum levels of CA195 and Dukes’ stage (p<0.001), grade of differentiation (p<0.01) and tumor location (p<0.05).

The results indicated that high preoperative serum levels of CEA and CA195 were associated with a shorter overall survival (p<0.0001). In addition, separate Cox multivariate analysis showed that preoperative CA195 was, after Dukes’ stage, the strongest factor to predict overall survival (p<0.0001).

Mucins: Structural diversity, biosynthesis, its role in pathogenesis and as possible therapeutic targets

Mucins are the main structural components of mucus that create a selective protective barrier for epithelial surface and also execute wide range of other physiological functions. Mucins can be classified into two types, namely secreted mucins and membrane bounded mucins. Alterations in mucin expression or glycosylation and mislocalization have been seen in various types of pathological conditions such as cancers, inflammatory bowel disease and ocular disease, which highlight the importance of mucin in maintaining homeostasis. Hence mucins can be used as attractive target for therapeutic intervention. In this review, we discuss in detail about the structural diversity of mucins; their biosynthesis; its role in pathogenesis; regulation and as possible therapeutic targets.

Serum CA 19-9 as a good prognostic biomarker in patients with bladder cancer

BACKGROUND

Bladder cancer (BC) is the second leading malignant tumors of the genitourinary system. CA 19-9 has served as a diagnostic and prognostic marker for pancreatic carcinoma for years. In recent year, although a few studies have evaluated the roles of CA 19-9 in BC, the results are conflicting and the number of the patients studied is very small.

AIM

To investigate the potential of serum CA 19-9 to serve as a diagnostic and prognostic marker of BC in a larger number of patients.

METHODS

A total of 272 (144 BC patients and 128 healthy subjects) were enrolled. Patients were followed-up routinely at 3-month intervals for 5 years. Serum CA 19-9 level was detected by ELISA.

RESULTS

CA 19-9 level was much higher than that in healthy subjects (43.69 ± 6.92 U/ml vs. 12.31 ± 4.39 U/ml, p < 0.001). However, when the value of 37 U/ml of serum CA 19-9 was used as the cut-off value for BC the sensitivity of CA 19-9 for BC was dropped to 38.8%. CA 19-9 was much higher in muscle invasive tumor subgroup than that in superficial tumor subgroup (38.09 ± 7.14 U/ml vs. 20.71 ± 4.15 U/ml, p < 0.027). CA 19-9 level was comparable in both subgroups (29.78 ± 5.07 U/ml vs. 26.13 ± 5.97 U/ml, p = 0.565). BC patients with more than 5 years survival time had lower serum CA 19-9 level than the rest (15.86 U/ml vs 46.68 U/ml, p < 0.001). Survival rate (>5 years) of patients with lower CA 19-9 levels (<29 U/ml) was significantly increased in comparison to those with elevated serum CA 19-9 levels (>29 U/ml) (p < 0.001).

CONCLUSIONS

serum CA 19-9 is not a good diagnostic maker, but a very powerful prognostic marker for BC. Such a study might be helpful for urologists to manage patients with BC.

Current status of mucins in the diagnosis and therapy of cancer

Mucins are the most abundant high molecular weight glycoproteins in mucus. Their nature and glycosylation content dictates the biochemical and biophysical properties of viscoelastic secretions, pointing out an important role in diverse biological functions, such as differentiation, cell adhesions, immune responses, and cell signaling. Mucins are expressed in tubular organs by specialized epithelial cells in the body. Their aberrant expression is well documented in a variety of inflammatory or malignant diseases. From a prognosis point of view, their expression and alterations in glycosylation are associated with the development and progression of malignant diseases. Therefore, mucins can be used as valuable markers to distinguish between normal and disease conditions. Indeed, this alteration in glycosylation patterns generates several epitopes in the oligosaccharide side chains that can be used as diagnostic and/or prognostic markers. Furthermore, these characteristic tumor-associated epitopes are extensively used as appropriate immunotargets of malignant epithelial cells. Therefore, in an effort to detect and treat cancer at the earliest stage possible, mucins are analyzed as potential markers of disease for diagnosis, progression, and for therapeutic purposes. In this review, we focused on the current status of the distribution of mucins in normal and pathologic conditions and their clinical use both in cancer diagnosis and therapeutics treatments.

Clinical relevance of serological markers in the detection and follow-up of pancreatic adenocarcinoma

Pancreatic adenocarcinoma is a relatively common malignancy and its incidence is increasing. Prognosis in these patients is poor, and surgery, the only effective treatment, saves only a minority of patients. The number in this small group of patients might be increased by early detection of pancreatic tumours. This review examines the current status of pancreatic tumour associated proteins in the detection of pancreatic cancer. As well as existing markers, the review also reports on newer markers that may offer advantages over existing ones in the detection of pancreatic adenocarcinoma. This is particularly important because recent studies have identified high-risk groups susceptible to pancreatic cancer. Future research in pancreatic cancer should be directed at earlier detection, and tumour markers may play an important role in this process.

Comparison of four serum tumour markers in the diagnosis of colorectal carcinoma

The assessment of the diagnostic power of four serum tumour markers, CEA, CA 19-9, CA 50 and CA 195 for colorectal carcinoma is described, according to recently formulated guidelines. Preoperative serum concentrations of the four markers were determined in 198 colorectal cancer patients and 57 patients with a benign colorectal disorder. The cumulative frequency distributions of the malignant and benign group show strong overlap for all markers, which indicates low diagnostic ability. This is confirmed by the Receiver Operating Characteristic curves, which have areas under the curve of 0.65 (95% confidence interval (CI) 0.58-0.73) for CA 19-9, CA 50 and CA 195 and of 0.70 (95%) CI 0.63-0.77) for CEA. The new tumour markers appear to be of slightly less diagnostic value than CEA for the primary diagnosis of colorectal cancer, although the discrepancy is not statistically significant. The low diagnostic power of CA 19-9, CA 50 and CA 195 may be due to a high proportion of colorectal cancer patients having the Lewis(a-b-) phenotype, who cannot synthesise these markers.

Tumor markers CA 19-9 and CA 195 are also useful as markers for cystic fibrosis

When monoclonal kits are used we can no longer detect highly elevated serum concentrations of carcinoembryonic antigen in cystic fibrosis (CF) patients as we could earlier (Pediatr Res 10:223-236, 1975). Instead, we find increased concentrations of CA 19-9 or CA 195 in the CF sera. The serum levels of CA 19-9 not only reflect the pulmonary condition of CF patients but also respond well to antibiotic therapy. Several lines of evidence suggest that the elevated serum concentration of CA 19-9 is derived from sputum and corresponds with the amount of sputum in the lung. Correlations between CA 19-9 and CA 195 in random and serial specimens from both patients with CF and patients with pancreatic carcinoma suggest that all sera contain heterogeneous, Lewis blood group-related epitopes and the proportions of various epitopes are different among individual patients. When monitored on multiple tumor markers, the pattern of CF is different from that of pancreatic carcinoma although both usually show elevated CA 19-9. Our study indicates that both CA 19-9 and CA 195 can be used as sensitive markers for the early detection of exacerbation in CF patients.

Comparative analysis of cancer-associated antigen CA-195, CA 19-9 and carcinoembryonic antigen in diagnosis, follow-up and monitoring of response to chemotherapy in patients with gastrointestinal cancer

To establish further the clinical significance of the CA-195 tandem immunoradiometric assay in gastro-intestinal malignancies, the sera of a total of 222 subjects have been analysed and compared with assays of the "classical gastrointestinal tumour markers", CA19-9 and carcinoembryonic antigen (CEA). CA-195 elevations above normal (greater than 10 U/ml) were noted in 51/72 (70.8%) colorectal, 15/15 (100%) pancreatic, and in 6/12 (50%) gastric cancer patients. Whereas CA19-9 was increased (greater than 37 U/ml) in 65%, 93%, and 42% of cases, only 54% colorectal, 45% pancreatic, and 42% gastric cancer patients had pathologically elevated serum CEA levels (greater than 5 ng/ml). No abnormal increase of both CA-195 and CA19-9 was found in healthy volunteers, whereas 3/20 (smoking) individuals had CEA levels slightly above normal. With a 29% false-positive rate noted among 103 patients with benign gastrointestinal disorders, the specificity of CA-195 was superior to that of CA19-9 (58%) and comparable with that of CEA (31%). A significant correlation between CA-195 levels and the clinical/pathological stage of disease was noted in colorectal (P less than 0.01) and pancreatic cancer patients (P less than 0.007). Preliminary results of serial measurements of CA-195 in colorectal cancer suggest that this new marker protein, which has no cross-reactivity with CEA, may be useful as a non-invasive test for postoperative surveillance of patients to detect disease recurrence, and serve to complement (though certainly not replace) standard clinical measurements of response to chemotherapy.

Evaluation of CEA, CA 19-9, CA-50, CA-195, and TATI with special reference to pancreatic disorders

The tumor markers CEA, CA 19-9, CA-50, CA-195, and TATI were analyzed in patients with pancreatic diseases as well as disorders in the upper quadrant of the abdomen. Two different methods for CA-50, namely CA-50 IRMA and CA-50 DELFIA, which are based on the same monoclonal antibody, were used. The sensitivities, specificities, and predictive values of positive and negative results were calculated at one, three, and ten multiples of the upper reference value ("cutoff") for each method. All the tumor markers except TATI had sensitivities exceeding 90% at one cutoff level, but CEA had low specificity. Poor sensitivities were observed for CEA and TATI at three cutoff levels, whereas CA 19-9, CA-50, and CA-195 had sensitivities and specificities greater than 80%. The sensitivities of these tumor markers decreased at 10 cutoff levels, although the specificities exceeded 95%. The predictive values of positive and negative results were also evaluated at these three cutoff levels. High scores were observed at three cutoff levels. Examined together with the sensitivity and specificity, the evaluation at three cutoff levels indicated that CA 19-9, CA-50, and CA-195 can be used in the diagnostic arsenal for the detection of cancer of the exocrine pancreas in symptomatic patients, and in the differential diagnosis between pancreatic cancer and chronic pancreatitis. Although CA-50 IRMA and CA-50 DELFIA are based on the same monoclonal antibody, there were substantial differences in the levels of CA-50 in a lot of the patients when samples were analyzed by the two methods. These differences were shown to be methodological, and they affected the test evaluations to some extent.