The influence of cholestasis on CA 50 and CA 242 in pancreatic cancer and benign biliopancreatic diseases

The sensitivity and specificity of serum glycan-based biomarkers for cancer detection

Most of clinically used serum biomarkers for cancer detection were established in early 1980s when the Nobel Prize in physiology or medicine was awarded for the "discovery of the principle for the production of monoclonal antibodies." Using this "Nobel" technology, various monoclonal antibodies were obtained when different types of cancer cells were injected into mice and the ligands on the cancer cell surface were characterized. Both aberrant glycan structures and aberrant glycan-associated glycoproteins were revealed as a common feature of cancer cell surfaces through the specific interactions with the monoclonal antibodies. These results indicate that the biosynthesis of the environment-sensitive glycan structures goes awry in cancer cells, which is beyond genetic mutations. Later on, the glycan-related biomarkers were detected in the sera of cancer patients and then developed into serum biomarkers, such as CA125, CA153, CA195, CA199, CA242, CA27.29, CA50, and CA724, which are still in clinical use as of today. During the past 30 years, even with the advancement of different OMICS technologies not limited to genomics, epigenomics, proteomics, glycomics, lipidomics, and metabolomics, very few serum biomarkers have been introduced into clinical practice. The reason is that most of the newly discovered cancer biomarkers are inferior in terms of sensitivity and specificity to these biomarkers. We will summarize the reported sensitivity and specificity of currently used cancer biomarkers, especially the glycan-related biomarkers, in the forms of tables and radar plots and discuss the pros and cons of currently used cancer biomarkers.

CA 19.9, CA 242 and CEA in the Diagnosis and Follow-up of Pancreatic Cancer

The diagnosis of pancreatic cancer is usually made in the advanced stages of the disease when the prognosis is poor. We compared the behavior of CA19.9, CEA and the newly proposed mucin CA242 in a consecutive series of 42 pancreatic carcinomas. A control group was recruited of 21 patients with benign pancreatic diseases. With the recommended cutoffs (37 U/ml for CA19.9, 20 U/ml for CA242 and 8 ng/ml for CEA) we obtained a specificity of 90% for CA19.9 and of 85% for CA242 and CEA. The sensitivity was 85.7% for CA19.9, 73.8% for CA242 and 26.2% for CEA. CA19.9 and CA242 showed identical behavior in various TNM stages of cancer and in stages HI and TV of the Hermreck classification. Moreover, CA19.9 and CA242 showed identical behavior in 10 patients monitored during the survival period who developed recurrence of disease. ROC curve evaluation demonstrated that CA242 and CA19.9 were very similar. The results of CA242 were better than those of CA19.9 in the false positive range under 10%, whereas CA19.9 had a better performance in the true positive range over 70%. CA242 could be used instead of CA19.9 for diagnosing pancreatic carcinoma.

Advances in diagnosis, treatment and palliation of pancreatic carcinoma: 1990-2010

Several advances in genetics, diagnosis and palliation of pancreatic cancer (PC) have occurred in the last decades. A multidisciplinary approach to this disease is therefore recommended. PC is relatively common as it is the fourth leading cause of cancer related mortality. Most patients present with obstructive jaundice, epigastric or back pain, weight loss and anorexia. Despite improvements in diagnostic modalities, the majority of cases are still detected in advanced stages. The only curative treatment for PC remains surgical resection. No more than 20% of patients are candidates for surgery at the time of diagnosis and survival remains quite poor as adjuvant therapies are not very effective. A small percentage of patients with borderline non-resectable PC might benefit from neo-adjuvant chemoradiation therapy enabling them to undergo resection; however, randomized controlled studies are needed to prove the benefits of this strategy. Patients with unresectable PC benefit from palliative interventions such as biliary decompression and celiac plexus block. Further clinical trials to evaluate new chemo and radiation protocols as well as identification of genetic markers for PC are needed to improve the overall survival of patients affected by PC, as the current overall 5-year survival rate of patients affected by PC is still less than 5%. The aim of this article is to review the most recent high quality literature on this topic.

Serum tumor markers in pancreatic cancer-recent discoveries

The low prevalence of pancreatic cancer remains an obstacle to the development of effective screening tools in an asymptomatic population. However, development of effective serologic markers still offers the potential for improvement of diagnostic capabilities, especially for subpopulations of patients with high risk for pancreatic cancer. The accurate identification of patients with pancreatic cancer and the exclusion of disease in those with benign disorders remain important goals. While clinical experience largely dismissed many candidate markers as useful markers of pancreatic cancer, CA19-9 continues to show promise. The present review highlights the development and the properties of different tumor markers in pancreatic cancer and their impact on the diagnostic and treatment of this aggressive disease.

Systematic review of carbohydrate antigen (CA 19-9) as a biochemical marker in the diagnosis of pancreatic cancer

BACKGROUND

Although many biochemical markers have been examined in pancreatic cancer none are definitive for pre-operative diagnosis. This systematic review examines studies using biochemical markers for the diagnosis of pancreatic cancer in order to appraise their role in contemporary management algorithms.

METHODS

A search of the MEDLINE database was undertaken using the key words pancreatic neoplasm and serum tumour marker. Only studies providing original data on sensitivity and specificity are included and data are presented on diagnostic accuracy, effect of cholestasis and the relation of tumour stage to blood levels of markers.

RESULTS

CA 19-9 is the most extensively evaluated with pooled data from 2283 patients. The median sensitivity of CA 19-9 for diagnosis is 79 (70-90%) and median specificity 82 (68-91%). CA 19-9 elevation in non-malignant jaundice results in a fall in specificity. Combination with other markers improves accuracy.

CONCLUSION

As the most extensively evaluated marker, CA 19-9 should be used in contemporary algorithms for the diagnosis of pancreatic cancer. Elevated values should be repeated after relief of jaundice.

A 3-year prospective study on serum tumor markers used for detecting cholangiocarcinoma in patients with primary sclerosing cholangitis

BACKGROUND/AIMS

Patients with primary sclerosing cholangitis (PSC) have an increased risk of developing cholangiocarcinoma (CC), which is notoriously difficult to diagnose since these patients may have increased levels of bilirubin due to benign strictures. To evaluate the validity of different tumor markers as an aid to diagnosing CC, we have carried out serial serum tumor marker analyses in patients with PSC who have been followed for several years.

METHODS

Seventy-five patients with PSC, without any clinical signs of CC were included in the study. They were investigated every 6th months for 3 years, with extensive liver function tests and four tumor serum markers CEA, CA 19-9, CA 50 and CA 242. The patients were then followed for 5 years to exclude the possibility that CC remained unrecognized.

RESULTS

Of the 75 patients, two (3%) developed CC during the 3-year period. One of these had normal levels, and one had significantly increased levels of the tumor markers. In the follow-up part of the study two further patients died from CC and one from hepatocellular carcinoma, 3 and 4 years after the 3-year study, respectively. Twenty-one patients had an increase of one of the markers on at least one occasion. Five patients had a transient increase of more than double the upper normal limit of the tumor markers on more than one occasion. There was a good correlation between CA 19-9, CA 50 and CA 242, but not with CEA. Fourteen of the 75 patients had periods of increased bilirubin levels, but none of these showed increased tumor markers.

CONCLUSIONS

The serum tumor markers CEA, CA 19-9, CA 50 and CA 242 are of limited value for the detection of CC in patients with PSC because of low specificity. However, we found no falsely increased values in patients with hyperbilirubinemia.

Serum CA 242: the search for a valid marker of pancreatic cancer

Many efforts have been made to find valuable serum tumour markers which help the diagnosis of pancreatic cancer. In the present study we investigated the diagnostic value of CA 242 in comparison with two other routinely used tumour markers (CA 19-9 and CA 50). Two-hundred and seventy six subjects were enrolled in this study: 46 patients with pancreatic cancer preoperatively, 53 with chronic pancreatitis, 28 with acute pancreatitis, 49 with other malignancies, 50 with miscellaneous non-neoplastic digestive diseases, and 50 healthy subjects. CA 242 was determined in serum by means of a two-step fluoroimmunometric assay. Sensitivities of CA 242, CA 19-9 and CA 50 for pancreatic cancer when all patients were considered were 41.3%, 54.3% and 47.8%, respectively (95% specificity level). No significant improvement was achieved by combination of CA 242 with CA 19-9 and/or CA 50. Cholestasis affected serum levels of CA 242 in patients without pancreatic cancer, but not in those with this tumour. The metastatic stage of pancreatic cancer appeared to influence the levels of CA 242. In conclusion, CA 242 serum assay does not seem to improve diagnostic accuracy for pancreatic cancer compared to CA 19-9 and CA 50.

Tumour marker CA 50 levels compared to signs and symptoms in the diagnosis of pancreatic cancer

The diagnostic merits of CA 50 and of symptoms indicating pancreatic cancer (pain, jaundice, weight loss, malabsorption) were compared prospectively in 512 consecutive patients. Among the final diagnoses were: exocrine pancreatic cancer, 175; periampullary cancer, 44; other gastrointestinal cancer, 45; and chronic pancreatitis, 64 cases. The suspected diagnoses based on symptoms and signs were correct in 80% of the patients with exocrine pancreatic cancer, in 78% with periampullary, in 76% with other gastrointestinal cancer and in 90% with chronic pancreatitis. CA 50 was pathological in 96% of the cases with exocrine pancreatic cancer, in 70% with periampullary, in 78% with other gastrointestinal malignancies and in 36% with chronic pancreatitis. The sensitivity was 96%, specificity 48%, positive prediction 49% and negative prediction 96%, depending on cut-off level. The single CA 50 value was comparable to symptoms and signs regarding sensitivity and negative prediction. In 28 of 42 cases incorrectly clinically classified, CA 50 alone indicated a benign or malignant diagnosis. If both the modalities 'signs and symptoms' and CA 50 were combined, the sensitivity was 91%, the specificity 92%, the positive prediction 86% and the negative prediction 95%. The initial CA 50 value can help to indicate in which patients a pancreatic malignancy should be suspected.

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.

Circulating blood group related carbohydrate antigens as tumour markers

The various blood group related carbohydrate structures which are in clinical use as circulating tumour makers are reviewed. Their location on carbohydrate chains and their structural characteristics are shown, and their clinical performance in various malignant diseases is reviewed. The available data on their sensitivity, specificity and predictive value are shown; and carcinomas of the pancreas, ventricle, colon-rectum and ovary are identified as diseases in which these markers can be of good benefit for follow-up. Future research should be devoted to studies of the function of these structures, and to studies of their gene-transcription.