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Query: UMLS:C0024623 (gastric cancer)
 36,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A computer-based file of all Veterans Administration (VA) hospitalisation records for the period 1969-1985 was used to identify and follow for cancer development a cohort of 5,161 white males with pernicious anaemia. A total of 34,915 person-years were accrued, with an average length of follow-up of 6.8 years. A total of 481 cancers were diagnosed, slightly higher than the number expected (SIR = 1.2). Significant excesses were observed for cancers of the buccal cavity and pharynx (1.8) and stomach (3.2), and for melanoma (2.1), multiple myeloma (2.1), myeloid leukaemia (3.7) and other and unspecified leukaemia (4.0). Although the excess for stomach cancer was highest in the first year after diagnosis in a VA hospital, risks of 2-fold or greater persisted throughout the study period. The majority of leukaemias occurred in the first year of follow-up, but some excess risk continued beyond this time. The elevated risk of buccal and pharyngeal cancers may relate to heavy alcohol intake among this population, although risks remained high even when the cohort was restricted to patients without an admission for alcoholism. Although an elevated risk of stomach cancer among pernicious anaemia patients is consistent with most previous surveys, the low absolute risk suggests that the cost-effectiveness of intensive screening should be reassessed.
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PMID:Cancer risk following pernicious anaemia. 273 18

Intragastric nitrosation has been implicated in the pathogenesis of gastric cancer and in precancerous conditions such as pernicious anaemia and the post-gastrectomy state. Intragastric nitrosation was assessed in at-risk patients by N-nitrosoproline (NPRO) excretion using both a conventional and a modified test. Twenty-four hour urinary excretion of NPRO was measured after oral administration of sodium nitrate (300 mg) and L-proline (500 mg) as an indirect indicator of intragastric nitrosation. In the conventional test no differences in intragastric nitrosation were found between at-risk patients and controls. In the modified test the loading dose of sodium nitrate was omitted and urinary NPRO levels were found to be significantly increased in Polya partial gastrectomy patients (P = 0.003) and post-vagotomy patients (P = 0.03) compared to controls. In pernicious anaemia patients NPRO levels were also higher than in controls but just failed to reach statistical significance. This study has confirmed that hypochlorhydria results in increased intragastric nitrosation, thus facilitating the formation of potentially carcinogenic N-nitroso compounds.
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PMID:Use of a modified N-nitrosoproline test to show intragastric nitrosation in patients at risk of gastric cancer. 276 71

Reduction in acid secretion in atrophic gastritis allows bacterial colonization of the stomach, most extremely in achlorhydric patients with pernicious anaemia, in whom overgrowth may cause nitrate reduction and formation of potentially carcinogenic N-nitroso compounds. Subsequent bacterial contamination of the upper small intestine can induce mucosal damage and malabsorption. The situation is similar after gastrectomy. In achlorhydria and after gastrectomy, the risk of gastric cancer is increased. There is controversy as to the risks of long-term treatment with H2-receptor antagonists. Increase in nitrate-reducing bacteria, nitrite and N-nitrosamine have been observed in patients by some investigators but not in volunteers and patients by others. Bacterial concentrations after cimetidine are inversely related to pretreatment acid secretory capacity. Demonstration of increased mutagenicity of gastric juice after H2-receptor antagonists gives grounds for caution. Drastic acid reduction may in future be reserved for short-term and intermittent treatment and mild or moderate reduction for long-term treatment of peptic ulcer and ulcer prevention.
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PMID:Bacterial overgrowth as a consequence of reduced gastric acidity. 286 52

The mutagenic activity of fasting gastric juice was assessed in 123 patients including 18 with normal endoscopic findings, 53 peptic ulceration, 9 gastric cancer, 12 pernicious anaemia and 31 patients who had undergone peptic ulcer surgery in the past. Significant mutagenic activity was detected in 96 (78%). Marked variations in mutagenic activity were noted both within and between the patient groups and no significant differences were detected. No correlation was found between mutagenic activity and patient age or sex, gastric pH, bile acid concentrations or bacterial counts, intestinal metaplasia on gastric mucosal biopsy, or intragastric nitrite. About 30% of gastric juice samples showed evidence of a cytotoxic activity towards the Salmonella tester strains in the mutation assay. Preliminary studies on other body fluids showed the presence of significant mutagenic activity in fasting saliva, bile and plasma. These findings demonstrate widespread human exposure to potentially genotoxic substances.
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PMID:The mutagenic activity of gastric juice. 304 33

In two prospective studies, including a total of 1,353 and 1,914 male and female participants, a variety of medical and psychosocial risk factors were assessed by means of personal interviews and observational categories. The incidence of gastric cancer was determined for the following study groups: 1) all persons with chronic atrophic gastritis and pernicious anemia who had one to three relatives with a history of gastric cancer, 2) persons with a previous operation for gastric ulcer (partial resection) and one to three relatives with gastric cancer, and 3) a comparable group without any of these characteristics, serving as a reference. The hypothesis was that significantly more gastric cancer was to be expected in groups 1 and 2. A second hypothesis was that interaction between the specific precursors and psychosocial risk factors (chronic hopelessness due to withdrawing objects) was useful for the prediction of gastric cancer. The results may open new avenues for the prevention of gastric cancer via preventive psychotherapy in identified risk groups.
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PMID:Precursor lesions of the GI tract and psychosocial risk factors for prediction and prevention of gastric cancer. 322 43

The introduction of ulcer-healing drugs that do not induce hypochlorhydria--the main aim of therapy thus far--has led to the consideration of the possible disadvantages of acid secretion inhibition. Potential dangers are that micro-organisms destroyed by the normal stomach survive and proliferate in the stomach and small intestine. The incidence of gastric cancer is higher in pernicious anemia and after partial gastrectomy. It has been suggested that the intragastric bacteria may convert dietary nitrate into nitrite that may then be nitrosated to carcinogenic N-nitroso compounds. The third potential hazard is the development of stagnant loop syndrome in patients treated with H2 antagonists. In a double-blind randomised trial of colloidal bismuth subcitrate (CBS) versus cimetidine in duodenal ulcer, gastric juice was aspirated for pH measurement. There was a significant increase in the total number of bacteria isolated during cimetidine treatment (P less than 0.01) and an increase in nitrate-reducing organisms (P less than 0.05), but no change in the CBS group. It is concluded that there may be advantages in using ulcer-healing drugs that do not reduce H+ concentration.
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PMID:Potential hazards of hypochlorhydria in the treatment of peptic ulcer. 353 17

The patient, a 5-year-old male, was diagnosed as having pernicious anemia at our hospital in 1969. By means of an upper G-I series, he was found to have a gastric protruded lesion on the greater curvature of the upper corpus in 1983. After an endoscopic polypectomy, a type II a early gastric cancer was diagnosed which, histologically, showed a well-differentiated adenocarcinoma and a total gastrectomy was performed. From the histologic findings of the resected stomach, the were multiple endocrine cell micronests, that coincided with the distribution of intestinal metaplasia localized in the fundic gland area.
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PMID:[A case of type IIa early gastric cancer complicated with multiple endocrine cell micronests in pernicious anemia]. 362 39

Two patients with intestinal metaplasia of the stomach, whose distribution was exclusively confined to the fundic gland area, are presented herein. The first, a 51-year-old male, had been treated for pernicious anemia for 14 years when he was found to have gastric cancer. His serum gastrin level was quite high, whereas his gastric acid output was markedly low. The polypoid cancer in the fornix of the stomach, which had been removed endoscopically, revealed tubular adenocarcinoma with its invasion limited to the mucosa. The resected stomach showed no residual carcinoma but had numerous minute foci of intestinal metaplasia, diffusely distributed but exclusively confined to the fundic gland area, by macroscopic observation using the leucine aminopeptidase-alkaline phosphatase double staining method. The intestinal metaplasias were all of the complete type, and the parietal and chief cells were almost completely lost. The second patient, a 76-year-old male without pernicious anemia, underwent total gastrectomy for two polypoid cancers in the body of the stomach. The resected specimens, in addition to two hyperplastic polyps in the transitional area, showed the same distribution of intestinal metaplasia as seen in the first patient.
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PMID:Intestinal metaplasia of the stomach confined to the fundic gland area. Report of two cases. 368 36

The activity of the DNA excision repair enzyme uracil-DNA glycosylase was measured in peripheral blood mononuclear cells and in bone marrow aspiration samples obtained from patients with pernicious anemia (PA) or other types of megaloblastic anemia (one case of tapeworm anemia and three cases of myelodysplastic syndromes). In addition, the expression of uracil-DNA glycosylase was investigated in biopsies from the antrum and body of the stomach obtained from nine PA patients, from five patients having atrophic gastritis (AG) not associated with PA, and from six control patients having transient upper abdominal complaints without AG. Our results revealed that there was a considerable interindividual variation in gastric uracil-DNA glycosylase activity. No clear correlation between the enzyme level and the level of gastric atrophy was noted, although AG is generally regarded as a risk factor of gastric cancer. Furthermore, uracil-DNA glycosylase activities in peripheral blood mononuclear cells and in bone marrow cells in PA and in myelodysplastic syndromes were similar to the activities observed previously in non-hematological patients and healthy persons. Transient uracil incorporation into DNA may have a role in the cellular abnormalities associated with megaloblastic hematopoiesis. The present findings demonstrated that the enzymatic activity required for rapid removal of uracil from DNA is also expressed in the megaloblastic state.
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PMID:Hematopoietic and gastric uracil-DNA glycosylase activity in megaloblastic anemia and in atrophic gastritis with special reference to pernicious anemia. 380 19

Achlorhydria, determined by the augmented histamine test, is the functional expression of the most severe atrophic gastritis and is followed by a 4- to 6-fold increased risk of gastric cancer, as we found 5 cancers in 114 patients after a mean observation period of 8.4 years. The cancers developed from 1 to 17 years after achlorhydria diagnosis--three cases after more than 9 years. The study showed no difference in gastric cancer risk between patients with and without pernicious anaemia. Spontaneous achlorhydria is the late result of atrophic gastritis, which should be regarded the premalignant condition. The development of gastric cancer from pharmacologically reduced acid secretion must be regarded as highly hypothetical, since this is not followed by atrophic gastritis.
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PMID:Gastric cancer risk in achlorhydric patients. A long-term follow-up study. 395 47


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