CEA mRNA identification in peripheral blood is feasible for colorectal, but not for gastric or pancreatic cancer staging.

OBJECTIVE: It has been suggested that the molecular identification of cancer cells in the circulation may be useful in predicting the presence of micrometastasis in several cancer types. The aim of the present study was therefore to assess the feasibility of CEA mRNA identification in blood for diagnosing and staging colorectal, gastric and pancreatic cancer. METHODS: We studied 16 control subjects, 69 patients with colorectal (CRC), 30 with gastric (GC), 27 with pancreatic cancer (PC) and 8 with benign diseases of the pancreatobiliary tree. At diagnosis CEA mRNA was identified in peripheral blood by means of a RT-PCR procedure. RESULTS: The specificity of this test in control subjects was 94%, and its sensitivity in identifying CRC, GC and PC were 34, 37 and 41%, respectively. False-positive findings were recorded in 25% patients with benign diseases. No association was found between CEA mRNA and stage in patients with GC or PC. In CRC patients, positive CEA mRNA findings were correlated with local spread (chi(2) = 14.6, p<0.01), lymph node (chi(2) = 18.95, p<0.001) and distant metastasis (chi(2) = 11.3, p<0.001). In these cases, CEA mRNA, but not CEA, was entered in stepwise discriminant analysis to classify the presence of lymph node metastasis. CONCLUSIONS: The molecular detection of micrometastasis in the blood by means of CEA mRNA identification is feasible for colorectal, but not for gastric or pancreatic cancer staging. Further studies are needed in order to define the clinical utility of this marker also in follow-up protocols.

ME-PCR for the identification of mutated K-ras in serum and bile of pancreatic cancer patients: an unsatisfactory technique for clinical applications.

Our aim was to assess the clinical reliability of mutated K-ras detection in serum or bile for the diagnosis of pancreatic cancer using ME-PCR. DNA was extracted from 1 ml serum obtained from 29 patients with pancreatic cancer and 12 control subjects. ME-PCR was optimized using a mixture of normal DNA added with different amounts of mutated DNA. The analysis of sera obtained from the 29 patients and of bile obtained from 11 pancreatic cancer patients demonstrated the presence of mutated K-ras in two (6.9%) and four cases (36%). By contrast K-ras was not amplifiable in any of the 12 serum samples obtained from healthy controls. In conclusion the DNA obtained from pancreatic cancer patients' sera is suitable for K-ras amplification and for the identification of codon 12 point mutations. However ME-PCR alone has an unsatisfactory sensitivity for the detection of pancreatic cancer using serum DNA as starting template.

Total PSA, free PSA/total PSA ratio, and molecular PSA detection in prostate cancer: which is clinically effective and when?

OBJECTIVES: To ascertain when the serum determination of the free prostate-specific antigen (PSA)/total PSA (fPSA/tPSA) ratio is clinically useful, and whether the identification of PSA or prostate-specific membrane antigen (PSM) mRNA in circulating cells has diagnostic advantages over the determination of their protein product. METHODS: fPSA, tPSA, and the fPSA/tPSA ratio were determined in the sera of 50 men with benign nonprostatic urologic diseases (EPD), 112 patients with prostate cancer (PCa), and 218 with benign prostatic hyperplasia (BPH). mRNA was extracted from the circulating mononuclear cells of 13 EPD samples, 25 PCa samples, and 38 BPH samples. PSA and PSM mRNA signals were identified in these samples by means of reverse transcriptase-polymerase chain reaction. RESULTS: Overall, at a fixed specificity of 95%, the sensitivity of tPSA was 19% and that of the fPSA/tPSA ratio was 40% in distinguishing PCa from BPH. The fPSA/tPSA ratio allowed the discrimination of PCa from BPH with satisfactory sensitivity and specificity when considering patients less than 60 years of age (100% and 95%, respectively). PSA and PSM mRNA were positive in 1 and 7 of 13 EPD samples, 6 and 13 of 25 PCa samples, and 6 and 17 of 38 BPH samples. The Gleason score did not correlate with tPSA, the fPSA/tPSA ratio, PSA mRNA, or PSM mRNA. CONCLUSIONS: The serum determination of the fPSA/tPSA ratio is an excellent index of PCa for subjects younger than 60 years of age; the clinical utility of PSA mRNA identification in circulating cells needs to be validated by large follow-up studies, and the analysis of PSM mRNA seems to be of no clinical interest.

Portal but not peripheral serum levels of interleukin 6 could interfere with glucose metabolism in patients with pancreatic cancer.

UNLABELLED: Interleukin 6 (IL-6), an autocrine growth factor for many tumors, seems to favour tumor spread to the liver. Our aims were first to evaluate the pattern of portal and systemic IL-6 levels in patients with pancreatic cancer (PC, n = 18) and chronic pancreatitis (CP, n = 22) compared with controls (CS, n = 20); and second, to ascertain whether there was any relation between IL-6 levels and tumor spread or PC-associated Diabetes mellitus. For all subjects, a fasting serum sample was obtained from a cubital vein; a portal serum sample was obtained from nine PC and three CP patients. In cubital and portal sera we measured IL-6, interleukin 1 beta (IL-1b), CA 19-9, c-reactive protein (CRP) and amylase. Systemic IL-6 levels were significantly higher in PC patients than in CS. In PC, portal IL-6 levels were significantly higher than the corresponding systemic values. The same pattern was found in the three CP patients, whereas IL-1b, CA 19-9, CRP and amylase portal levels were the same as systemic values. No correlation was found between PC stage and systemic or portal IL-6 levels. Portal IL-6 levels were correlated with the corresponding fasting serum glucose values. A significant correlation was found between IL-6 values and CRP, ALT, total bilirubin, GGT and creatinine, but not amylase. IN CONCLUSION: (1) Portal IL-6, which is partly of pancreatic origin, is first metabolised in the liver; (2) Systemic IL-6 reflects hepatic and renal functions rather than local conditions in the pancreas; (3) IL-6 does not appear to influence PC spread; (4) IL-6, which is released in large amounts by the inflamed pancreas, may contribute to determining diabetes, thus interfering with the signal transducing pathways involved in glucose metabolism in liver cells.

Analysis of Helicobacter pylori vacA and cagA genotypes and serum antibody profile in benign and malignant gastroduodenal diseases.

BACKGROUND: Helicobacter pylori species comprise different strains, cytotoxic and non-cytotoxic, which can be identified on the basis of their genomic pattern. AIMS: (1) To evaluate the polymorphism of the vacA gene and to ascertain whether the cagA gene is present in patients with gastric adenocarcinoma. (2) To study the anti-H pylori antibody profile using western blotting. PATIENTS: Twenty one patients with gastric adenocarcinoma and 71 with H pylori associated benign disease (nine gastric ulcer, 29 duodenal ulcer, 25 antral gastritis, and eight duodenitis). METHODS: The polymerase chain reaction was used to verify the presence or absence of cagA and to study the polymorphism of vacA in gastric mucosal samples obtained during endoscopy for patients with benign diseases and at surgery for patients with gastric adenocarcinoma. Fasting sera were used to assess anti-H pylori antibodies against different H pylori antigens by western blotting. RESULTS: CagA gene and the allele s1 of vacA were significantly less frequent in patients with antral gastritis (60% and 60%) compared with patients with gastric adenocarcinoma (94% and 100%) and with other non-malignant gastroduodenal diseases (93% and 87%) (chi 2 = 16.01, p < 0.001; and chi 2 = 13.97, p < 0.01). In patients with gastric adenocarcinoma, antibodies against a 74 kDa H pylori antigen were less frequently found than in patients with benign diseases. CONCLUSIONS: H pylori infection caused by cagA positive/vacA s1 strains is a frequent finding in patients with gastric adenocarcinoma. Prospective studies are needed to confirm whether the low incidence of positive serological response to the 74 kDa H pylori antigen in patients with gastric adenocarcinoma is important.