Benign Gastrointestinal Diseases Research Articles

Molecular Detection of Codon 12 K-RAS Mutations in Circulating DNA from Serum of Colorectal Cancer Patients

Point mutations of the K-RAS gene at codon 12 are found in about 40% of cases with colorectal cancer. The diagnostic implications of the detection of these mutations and their clinical utility are still unclear. The aim of this study was to test both the feasibility of the detection of the mutated K-RAS gene in serum and its potential role in colorectal cancer detection and monitoring. Codon 12 K-RAS mutations were examined in DNA extracted from the serum of 35 patients with colorectal cancer and were compared with the K-RAS status in the corresponding primary tumor. Molecular detection was performed by the mutant-enriched PCR (ME-PCR) assay, a sensitive method capable of distinguishing a small quantity of mutated DNA in the presence of abundant wild-type DNA. The occurrence of mutations was compared with clinicopathological parameters as well as CEA and CA19.9 serum levels. We found codon 12 K-RAS mutations in the tissue of 13/35 (37%) patients. Serum mutations were detected in 5/13 (38.5%) patients with mutated K-RAS in the tissue. 26/35 (74%) patients showed an identical K-RAS pattern in tissue and serum. No codon 12 K-RAS alterations were found in serum samples of 22 patients with benign gastrointestinal diseases. Elevated serum CEA levels were detected in 16 patients, four of whom also presented serum RAS mutations. Our results confirm that K-RAS mutations can be found in circulating DNA extracted from serum samples of patients with colorectal cancer and show that there is a correspondence between serum and tissue K-RAS patterns.

Nutrition for surgical patients: a brief overview

As the emphasis on reducing health-care costs shape the attitudes and practices of physicians today, surgeons will be urged to use preventative efforts to shorten length of stay. When used properly, nutritional support has been shown to decrease the incidence of infection and reduce hospital length of stay. In addition, as early as 1936, Studley recognized that malnutrition significantly decreased postoperative morbidity and mortality.1 As a result, attempts to define parameters that could be used to recognize malnutrition preoperatively in surgical patients were made. Weight loss, loss of arm muscle bulk, anemia, vitamin deficiency, and low plasma levels of transferrin and albumin were found to be useful indicators.2 These variables are helpful in identifying protein-calorie malnutrition, but no single variable has been predictive of patient outcome. However, combining several variables has been shown to be more predictive. For example, a prognostic nutrition index defines malnutrition as patients with a serum albumin of ,3.5 g/dL and a recent weight loss of .10% in addition to any two of the following: weight for height, mid-arm circumference, or triceps skin-fold thickness ,10th percentile.3 In patients undergoing elective operation for benign gastrointestinal disease, the prognostic nutrition index was found to be simple and useful in determining malnutrition and its effect on postoperative outcome.3

A monoclonal antibody specific to the granulocyte-derived elastase-fragment D species of human fibrinogen and fibrin: its application to the measurement of granulocyte-derived elastase digests in plasma

When granulocytes are stimulated under certain clinical conditions, elastase is released therefrom and digests fibrin(ogen) independently of the plasmin system, which may also be mobilized simultaneously. Thus, discrimination of these 2 systems becomes urgent for the diagnosis and treatment of the underlying diseases. Using as immunogen a 97-kd granulocyte-elastase digest of human fibrinogen, we raised an antibody IF-123 that specifically recognizes elastase digests of human fibrin(ogen). The 97-kd elastase fragment resembles plasmic fragment D(1), and the epitope of this antibody is located on the Aalpha (196-204) residue segment. This segment appears to be masked in fibrin(ogen) but exposed when the Aalpha Leu 204-Ile 205 peptide bond is cleaved by elastase. Cathepsin G concomitantly released from granulocytes failed to expose the epitope. By an enzyme immunoassay using IF-123 as the capture antibody, the elastase digests of fibrin(ogen) can be measured in plasma samples without interference by abundantly coexisting fibrinogen. Indeed, we found that the elastase digests were mostly elevated in patients with inflammation or malignant tumors, but remained in a normal range in patients with a benign gastrointestinal tract disease such as duodenal ulcer and polyps in the gallbladder or the colon. Like the plasmic D-dimer, the elastase digests predominantly consisted of the DD/E complex and DD/E-containing high-molecular weight derivatives apparently corresponding to the phase-3 plasmic digests of cross-linked fibrin. (Blood. 2000;95:1721-1728)

Diagnostic, prognostic and monitoring value of CA 72.4 in gastric cancer. A prospective study including CA 19.9 and CEA

The diagnostic, prognostic and monitoring value of CA 72.4 in gastric cancer was prospectively studied, in parallel with CA 19.9 and CEA. Thirty-eight patients with primary gastric carcinoma were included in a prospective two-year study. The mean values of CA 72.4 and CA 19.9 before surgery were statistically different from those of a control group (n = 38) with benign gastro-intestinal (GI) diseases. CA 72.4 adds independent complementary sensitivity to CEA and CA 19.9. According to the ROC analysis, the highest area under the ROC curve was that of CA 72.4 (0.75 ± 0.06), followed by CA 19.9 (0.64 ± 0.07) and CEA (0.53 ± 0.07). Using the “kinetic profile” index, prognostic studies revealed significant correlations between CEA (at days 0, 7 and 14) and overall survival. In the patients with no evidence of disease nor progression, the true negative rate of CA 72.4 was higher (100 %) than that of CEA (86.7 %) and CA 19.9 (73.3 %) ; the false positive rate was 0 %, 13.3 % and 26.7 % for CA 72.4, CEA and CA 19.9, respectively, and highlighting the absolute specificity of CA 72.4. A higher true positive rate for detecting progressive disease or recurrence was noted for CA 72.4 (81.6 %) than for CEA (54.5 %) and CA 19.9 (45.5 %). CA 72.4 may constitute a useful test assisting in the clinical management of gastric cancer patients. Les valeurs diagnostique, pronostique et dans le suivi du CA 72.4 dans le cancer de l'estomac ont été étudiées parallèlement avec le CA 19.9 et l'ACE. Trente-huit patients présentant un cancer gastrique ont été inclus dans cette étude prospective de deux ans. Les taux moyens de CA 72.4 et de CA 19.9 avant chirurgie sont statistiquement différents de ceux du groupe contrôle (n = 38), constitué de pathologies gastro-intestinales bénignes. Le CA 72.4 ajoute une sensibilité indépendante complémentaire à l'ACE et au CA 19.9. Conformément à l'analyse ROC, l'aire sous la courbe ROC la plus élevée était celle du CA 72.4 (0,75 ± 0,06), suivie de celle du CA 19.9 (0,64 ± 0,07) et de l'ACE (0,53 ± 0,07). Utilisant l'index de ≪ profil cinétique≫, les études pronostiques ont révélé des corrélations significatives entre l'ACE (aux jours 0,7 et 14) et la survie globale. Chez les malades sans progression, le taux de vrais négatifs de l'ACE était supérieur (100 %) à celui de l'ACE (86,7 %) et du CA 19.9 (73,3 %) ; le taux de faux positifs était respectivement de 0 %, 13,3 % et 26,7 % pour le CA 72.4, l'ACE et le CA 19.9, mettant en valeur la spécificité absolue du CA 72.4. Un taux de vrais positifs plus élevé pour la détection des récidives a été noté pour le CA 72.4 (81,6 %), comparativement à l'ACE (54,5 %) et au CA 19.9 (45,4 %).Le CA 72.4 peut constituer un test utile dans la prise en charge du cancer gastrique.

B72.3 immunoreactivity in benign abdominal lymph nodes associated with gastrointestinal disease.

Immunolocalization of the tumor-associated glycoprotein 72 antigen with the monoclonal antibody B72.3 has been used as a "cancer marker" in radioimmunoscintigraphy and radioimmunoguided surgery (RIGS). Radioimmunoscintigraphy and RIGS have been used to detect occult metastatic deposits from colorectal adenocarcinoma. It has been suggested that RIGS is superior to histologic examination in detecting lymph node metastases from colorectal cancer. To determine the specificity of immunodetection of the tumor-associated glycoprotein-72 antigen as a marker for metastatic adenocarcinoma, we studied benign intra-abdominal lymph nodes with B72.3 and an immunohistochemical technique. Formaldehyde-fixed, paraffin-embedded sections of 276 benign abdominal lymph nodes, resected with 35 cases of colonic adenocarcinoma and 33 cases of benign gastrointestinal disorders, were evaluated for B72.3 immunoreactivity using an avidin-biotin complex immunohistochemical technique. Lymph nodes from cases of colonic carcinoma were also studied with cytokeratin immunostaining to help eliminate occult micrometastases. B72.3 immunoreactivity was seen in the germinal centers of benign lymph nodes associated with 49 percent of the cases of colonic adenocarcinoma and 12 percent of the cases of benign gastrointestinal disease. B72.3 immunoreactivity can be seen in benign abdominal lymph nodes associated with gastrointestinal disease. We advise caution in the use of diagnostic techniques that equate B72.3 immunoreactivity with the presence of adenocarcinoma.

SERUM CYTOKERATIN-19 MEASURED BY CYFRA21-1 ASSAY IN PATIENTS WITH GASTROINTESTINAL AND GYNECOLOGIC MALIGNANCY

The serum fragment of cytokeratin 19 was measured in 130 patients with gastrointestinal, breast and gynecologic cancer and 62 patients with benign disease using CYFRA21-1 immunoradiometric assay. Patients with advanced cancer showed the highest level of serum CYFRA21-1. When the cut-off level was set at 2 ng/ml, 7 of 61 patients with earlier stage cancer were positive whereas 45 of 69 patients with advanced cancer had serum CYFRA21-1 levels over 2 ng/ml. In benign gastrointestinal and gynecologic diseases, 4 of 66 patients were positive. Retrospective evaluation revealed a good correlation between the serum CYFRA21-1 concentration and clinical course. CYFRA21-1 may be a useful tumor marker for monitoring of gastrointestinal and gynecologic malignancies.

Growth Factors in Benign Gastrointestinal Diseases

Mucosal ulceration in the gastrointestinal tract leads to the development of a novel cell lineage which locally secretes growth factors such as trefoil peptides and epidermal growth factor (EGF). Gastric mucosal ulceration causes an increase of EGF receptor density and a profound decrease of somatostatin receptor density in the mucosal ulcer margin and scar. These changes in growth factors and their receptors cause a strong increase of cell proliferation in the ulcer margin. In experimental ulcer models, EGF and basic fibroblast growth factor (bFGF) promote ulcer healing by increasing epithelial cell proliferation and angiogenesis, respectively. Indomethacin delays ulcer healing by decreasing epithelial cell proliferation, inhibition of angiogenesis, and inhibition of remodelling of the granulation tissue in the ulcer base. Indomethacin interferes with EGF binding and proliferative response of gastric cultured KATO III cells. In addition, bFGF cannot reverse indomethacin-induced deleterious effects on experimental gastric ulcer healing. In summary, growth factors play an important role in promoting wound healing in benign gastrointestinal diseases.

Role of Psychological Factors in the Irritable Bowel Syndrome

Our study was designed to test the hypothesis that psychoneurosis in irritable bowel syndrome (IBS) may be the secondary effects of the unsatisfactory nature of the medical transactions (diagnosis, explanation, prognosis, and therapy) in IBS rather than a primary cause of the syndrome. We carried out psychometric assessments on three groups of subjects: 10 healthy volunteers, 12 patients diagnosed as suffering from benign gastrointestinal disease, and 18 patients with IBS. We found a significantly raised incidence of psychoneurosis in IBS, but the components of this were predominantly anxiety and obsession; the incidence of depression in all 3 groups was similar. We argue that the data support our hypothesis that the psychoneurotic manifestations are secondary components of IBS; the data do not support the hypothesis that IBS is a manifestation of depression.

Diet-induced thermogenesis in patients with gastrointestinal cancer cachexia.

1. Indirect calorimetry has been used to measure resting energy expenditure (REE) and the thermogenic response to a test meal (diet-induced thermogenesis) in groups of weight-stable and weight-losing patients with gastrointestinal adenocarcinoma. Average daily intakes of energy and protein were computed from dietary assessment for the week before hospitalization. Results were compared with a control group of patients with benign gastrointestinal disease. 2. Weight-losing cancer patients had a significantly reduced mean total energy and protein intake. 3. There was no significant difference in REE between the groups when results were normalized in terms of metabolic body size (kJ/kg 0.75) and lean body mass (kJ/kg). 4. Diet-induced thermogenesis was reduced in weight-losing cancer patients. 5. It is suggested that the reduction of diet-induced thermogenesis in weight-losing cancer patients is another element of starvation adaptation, subsequent to their weight loss, and that altered thermogenesis does not contribute to the weight loss seen in cancer cachexia.

Serum glutathione-S-transferase-pi as a tumor marker for gastrointestinal malignancies.

A glutathione-S-transferase-pi (GST-pi) immunoradiometric assay was devised as a potential marker for serodiagnosis of malignant disease. Elevated serum GST-pi levels were observed in patients with various gastrointestinal malignancies including gastric, esophageal, colonic, pancreatic, hepatocellular, and biliary tract cancers. Patients with benign gastrointestinal diseases had normal GST-pi, but some patients with chronic hepatitis and cirrhosis had slightly elevated levels. Over 80% of patients with Stage III or IV gastric cancer and even about 50% of those with Stage I and II had elevated serum GST-pi. After surgery serum GST-pi levels returned to normal. Resected stomach cancers were immunohistochemically positive for GST-pi. During chemotherapy of colonic, gastric, and hepatocellular cancers with a series of different drugs, GST-pi changed in a biphasic manner; increases during initial phases of therapy may reflect acquisition of drug resistance by the tumor. In general, serum GST-pi assays provide a sensitive and reliable marker for gastrointestinal malignancies.

Monoclonal antibody assays for measuring ovarian tumor antigen in blood. Detection of NB/70K in patients with ovarian cancer and nongynecologic diseases.

Blood levels of human ovarian tumor antigen NB/70K were measured using four different monoclonal anti-NB/70K antibody radioimmunoassays (NB12123, NB12913, NB13834, and NB13831 assays). Four hundred thirty-two blood samples were obtained from apparently disease-free controls, from patients with benign and malignant ovarian tumors, and from patients with benign nontumorous and malignant diseases of the breast, lung, and gastrointestinal systems. The means, medians, and percent of samples that had elevated levels of NB/70K were calculated for each group of patients or controls for each assay. For all control versus malignant disease comparisons, there were statistically significant differences in all assays. For all benign versus malignant disease comparisons in the ovary, breast, lung, and gastrointestinal systems, there were statistically significant differences in all assays with the exception of the benign versus malignant gastrointestinal disease comparison in the NB12123 assay. Elevated NB/70K levels were detected in blood from ovarian cancer patients, almost all of whom had adenocarcinomas. Elevated NB/70K levels were also detected in blood samples from patients with adenocarcinoma, squamous, and clear cell carcinomas of the lung as well as in adenocarcinoma and ductal carcinoma of the breast. These results indicate that NB/70K is a marker for different pathologic types of malignancies.

The effect of nutritional status on morbidity after elective surgery for benign gastrointestinal disease.

The effect of nutritional status on the morbidity and mortality of major gastrointestinal surgery for benign disease was studied in 32 patients. Malnutrition was defined as a serum albumin less than 3.5 g/dl and a recent weight loss greater than 10%, in addition to any two of the following: weight for height, midarm circumference or triceps skin-fold thickness less than 10th percentile. The morbidity and mortality in the 17 malnourished patients was 59% and 29%, respectively, compared with 20% and 7% in 15 well-nourished patients matched for age and operative procedure (p less than 0.05). After operation, the mean duration of inadequate oral nutritional intake period (IONIP, defined as a caloric intake greater than 60% requirement) was 11.9 days +/- 2.9 (SEM) in well-nourished patients compared with 30.5 days +/- 3.7 in the malnourished group. The longer IONIP in malnourished patients was a consequence of the higher morbidity in this group, thus warranting the consideration of supportive (postoperative) parenteral nutrition in malnourished patients who undergo major gastrointestinal surgery for benign disease.

Body composition in malignant disease

It has been suggested that adaptation to starvation may be impaired in patients with malignant disease and that this may contribute to the development of cancer cachexia. We have investigated this by comparing the body composition, as well as the tissue composition of weight loss, of a group of 49 patients with gastrointestinal carcinomas and 91 patients with benign gastrointestinal disease all of whom had sustained a weight loss greater than 10% of their recalled preillness weight. Total body protein was calculated from total body nitrogen measured by in vivo neutron activation analysis which also provided absolute values of sodium, chlorine, phosphorus, and calcium. The masses of muscle and nonmuscle protein were estimated using a validated compartmental analysis. Total body fat was derived using anthropometry. Total body water was estimated from the difference between body weight and the sum of body protein, fat, and minerals. The loss of body weight incurred by patients with both benign and malignant disease was primarily muscle mass and body fat. Both groups of patients retained nonmuscle protein. All patients manifested, with increasing weight loss, a progressive loss of muscle protein, fat, and water, which must represent the tissue composition of weight loss. No significant differences between patients with benign or malignant disease were demonstrated for any of the body composition parameters measured. The results of this study do not support the hypothesis that adaptation to starvation in patients with cancer is in anyway different from that which occurs in patients with benign disease.

The Effect of Nutritional Status on Morbidity after Elective Surgery for Benign Gastrointestinal Disease

The Effect of Nutritional Status on Morbidity after Elective Surgery for Benign Gastrointestinal Disease

Prospective evaluation of the diagnostic efficacy of CA 19-9 assay as a marker for gastrointestinal cancers.

Levels of a new carbohydrate antigen, CA 19-9, which is a monosialoganglioside identified by a monoclonal antibody raised against colorectal carcinoma cells, were compared to conventional CEA assays in 615 sera from healthy controls, patients with benign gastrointestinal disorders, and patients with cancers of gastrointestinal or extragastrointestinal origin. Whereas CEA levels were higher in smokers, CA 19-9 values were independent of the smoking history. CA 19-9 was undetectable in lymphoma and myeloma patients, but some patients with extraintestinal epithelial cancers expressed this antigen in serum. For benign and malignant gastrointestinal diseases, CA 19-9 displayed higher sensitivity, specificity, and predictive values than CEA. CA 19-9 was elevated as frequently as CEA in patients with metastatic pancreatic cancer, but in patients with localized disease, CA 19-9 was elevated more often than was CEA. In colorectal cancer, patients with and without metastases were detected at similar rates by both assays. It is concluded that CA 19-9 is a marker of epithelial cancers, does not vary with the smoking status, and is superior to CEA in detecting gastrointestinal malignancies, especially those arising from the pancreatic gland.

Hypothesis testing in the polychotomous logistic model with an application to detecting gastrointestinal cancer

We discuss the use of the trichotomous logistic model to discriminate between patients with gastrointestinal (GI) cancer, patients with benign GI disease and 'normal' subjects, using symptoms and the concentrations of some serum proteins that are potentially indicative of malignancy as covariates. A parsimonious model can be obtained by invoking an indistinguishability hypothesis which is appropriate when a covariate is considered to have no predictive value between categories. It is shown that the polychotomous model can be re-parameterised under the null hypothesis to give a 'reduced form', which can be fitted by maximum likelihood. The validity of the use of the same methods for retrospective sampling is discussed. The approach is illustrated by the development of a logistic model to identify symptomatic and asymptomatic subjects with a high risk of GI cancer.

Clinical relevance of regulatory gastrointestinal peptides

The application of radioimmunoassay of insulin, C-peptide, gastrin, glucagon, vasoactive intestinal polypeptides (VIP), somatostatin, human pancreatic polypeptides (hPP), substance P and neurotensin to detect endocrine tumors of the pancreas and other organ systems is undoubtedly important in the clinical management of patients suspected of having tumors that secrete these hormones. Radioimmunoassays of the above gut peptides have certain degrees of specificity and sensitivity; however, there are several factors that need to be considered in the interpretation of results since heterogeneity of molecular forms does occur and the varied radioimmunoassay techniques use different antibodies that may yield different results. It is, therefore, important that each laboratory establish its own normal values, determine the molecular species that each assay is detecting, and also determine the false positivity of the methodology. The same endocrine tumor may contain and secrete several detectable peptides, but the syndrome may relate to only one peptide. Although the simultaneous measurement of multiple peptides in patients with benign gastrointestinal disease has yielded information that contributes to our understanding of the complexities of gut neuroendocrine interaction, the pathophysiological role of gut peptides and their clinical relevance need further evaluation.

Evaluation of an enzyme-linked immunosorbent Raji cell assay (ELISA) in the investigation of gastrointestinal cancer.

The levels of circulating immune complexes (CICs) have been estimated in a group of patients with colorectal cancer and gastric cancer, in addition to which a normal range has been established in a group of patients with benign gastrointestinal disease. A newly developed enzyme-linked immunosorbent Raji cell assay has been used in this study. Overall only 30% of patients with gastrointestinal cancer showed elevation of CIC levels outside the normal range. Elevated levels correlated with tumour differentiation bud did not correlate with site of disease or with the presence of metastases. In an attempt to define the specificity of CIC estimation, soluble tumour extract was added to sera from tumour-bearing patients. Specific IC elevations were produced by addition of allogeneic tumour extract of colon cancer in patients with colorectal cancer; this phenomenon was not seen when the same extract was added to the sera of patients with gastric cancer.

Immunoassessment of patients with gastric cancer. Using leukocyte migration inhibition (LMI) test.

Leukocytes from patients with gastric, colorectal or benign gastrointestinal disease, as well as those from normal control subjects, were tested by the leukocyte migration inhibition test (LMIT), using five different allogeneic 3 M KCl extracts of gastric cancer extracts. In LMIT with a single tumor extract, a pathological MI was found in 48% of 79 gastric cancer patients, a significantly higher figure than in the three other groups of patients (4-21%). In the panel mode of LMIT, that is, testing each blood sample with five different tumor extracts, 62/79 (79%) of patients with gastric cancer showed a positive reaction. Positive reactivity was significantly higher in patients with gastric cancer than in patients in the other groups and the frequency was higher in stage IV cases than in stage I-III cases, although the differences were not significant. In addition, the frequency of the positive reaction was unrelated to the degree of differentiation in adenocarcinoma. Positive reactivity increased in inverse proportion to the degree of nuclear grade (NG) (84% in NG I, 80% in NG II and 64% in NG III), but the correlation was not statistically significant.

Detection of liver metastases with 5'-nucleotide phosphodiesterase isozyme-V in gastrointestinal cancer patients.

An evaluation of the 5'-nucleotide phosphodiesterase isozyme V (5'-NPD-V) test for liver metastases in gastrointestinal (GI) cancer patients was undertaken with a coded serum panel provided by NCI Mayo Clinic. Upon decoding, 28 of 30 patients (93%) with known liver metastases and 11 or 32 patients (36%) with no known liver metastases were positive. In 20 patients with various benign GI diseases, there were 6 (30%) positive for 5'-NPD-V. 2 of these positive patients with benign GI diseases had identifiable liver disorders. Statistical analysis of the data supports 5'-NPD-V can discriminate between GI cancer patients with and without liver metastases and patients with benign GI diseases.