摘要:

The hereditary breast (BC) and ovarian (OC) cancer syndrome (HBOC) includes genetic alterations of various susceptibility genes such as TP53. ATM, PTEN or MSH2, MLH1, PMS1, PMS2, MSH3 and MSH6, BRCA1 and BRCA2. Germline mutations of the cancer-susceptibility genes BRCA1 and BRCA2 seem to be the major aetiology of the HBOC. Genetic counselling and identification of high-risk families may be essential (1) to provide the best method for genetic testing by explaining the sensitivity and specificity of the methods. (2) to offer the opportunity to participate in specific early cancer detection programmes (breast (self) palpation, ultrasound, mammography and magnetic resonance tomography for breast cancer, vaginal exploration and ultrasound for ovarian cancer), (3) to inform them about prophylactic medication (oral contraceptive pill (OCP), chemoprevention (tamoxifen, raloxifen, aromatase inhibitors)) or surgery (bilateral prophylactic mastectomy or oophorectomy) and (4) to provide individualized psychological support. To fulfil these broad demands, an inter-disciplinary counselling approach (gynaecological oncology, human genetics, molecular biology, psychotherapy) in the setting of a cancer genetic clinic seems the most appropriate. There, participation in predictive genetic testing or the use of preventive or therapeutic options may be discussed extensively with the subjects. In particular, preventive options are emotionally disturbing for the subjects, and in cases of previous cancer. BC chemoprevention for high-risk women does not seem to be as effective as expected. However. OCP reduces the risk for OC. For prophylactic surgery, various points have to be considered, including: (1) individual risk assessment and gain in life expectancy. (2) value of screening and early detection methods or medical prevention, (3) disease characteristics and prognosis, and (4) anxiety and quality of life. Decisions regarding these options have to he individualized and psychological support must be offered during the period of decision and follow-up.

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

In view of the direct contact between food residues and metabolites and the large bowel mucosa, it might be expected that food consumption patterns would affect the risk of colorectal carcinogenesis. Many lines of evidence support the adenoma-carcinoma sequence as the major mechanism of colorectal carcinogenesis. The present study aimed to investigate the role of foods of animal origin such as meat, dairy products and eggs in the early stages of colorectal carcinogenesis. Eleven case-control and two cohort studies on colorectal polyps and meat, dairy products and eggs were identified. A quantitative review of these studies and a meta-analysis were carried out. The combined odds ratios suggest a positive association between the risk of colorectal polyps and beef consumption and a negative association with fish or combined poultry/fish consumption. An increase in the ratio of the consumption of red meat to consumption of fish/chicken was associated with an increase in the colorectal polyp risk. Neither dairy product nor egg consumption had a substantial effect on the development of colorectal polyps. These results suggest that dietary factors associated with polyp development may be not the same as those associated with cancer.

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Secondary bile acids, by virtue of their lipophilic action, change the membrane composition of hepatocyte mitochondria, the inner membranes of which harbour the cytochrome P450 oxido-reductase system. The changes in the membrane fatty acid composition decreases the activity of the mitochondrial enzyme system, thereby making them incapable of handling free radicals generated during the normal process of energy production and detoxification. These free radicals in turn may attack membrane polyunsaturated fatty acids to initiate and propagate lipid peroxidation, leading to formation of aldehydic lipid peroxidation products. Notably among these is 4-hydroxynonenal, which has a high genotoxic and neoplastic potential. Disorders of gallbladder contractility further lead to accumulation of these toxic substances normally excreted in bile, and if retained for long time in the gallbladder they may induce gallbladder carcinogenesis.

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Insulin-like growth factor 1 (IGF-1) is a potentially important determinant of disease; hence epidemiological identification of factors that influence circulating IFG-1 is merited. We therefore analysed data collected in Greece to determine the relationship between anthropometric, lifestyle and dietary variables and serum levels of IGF-1 among elderly men. We identified 51 men with prostate cancer, 50 men with benign prostatic hyperplasia. and 52 apparently healthy elderly men (controls), all matched for age (± 1 year). These 153 men provided blood specimens and were interviewed using a validated lifestyle and food frequency questionnaire. We performed multivariate linear regression to identify potential predictors of circulating IGF-1. After controlling for age, body mass index, smoking habits, alcohol drinking and coffee consumption, each 5 cm increase in height predicted a 13.0% increase in IGF-1 (95% CI 0.4–27.2%) among the controls and a 11.3% increase in IGF-1 (95% CI 4.5–18.6%) among the entire study group. None of the investigated dietary factors (total fat. carbohydrate, protein, dairy products, tomatoes, calcium) were strongly related to IGF-1 levels. The positive association between IGF-1 and height integrates the empirical evidence linking IGF-1 and height with prostate cancer risk.

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Death certification data from pleural cancer in eight European countries providing data to the World Health Organization database over the period 1970–1994 were analysed using a log-linear Poisson model to disentangle the effects of age, birth cohort and period of death. The age effect reached values between 10 and 15/100 000 males at age 80–84 in most countries, except Hungary (6.7), Switzerland (18.0), France (20.6) and the Netherlands (36.5). Cohort effects were steadily and appreciably upwards in all countries up to the generations born in 1940 or 1945, and levelled off for the 1950 cohort, except in Hungary, where persistent rises were observed. Thus, most rises in pleural cancer mortality in Europe were on a cohort of birth basis. Since most pleural cases were asbestos-related mesotheliomas, and since asbestos has an early-stage effect on subsequent mesothelioma risk, exposure early in life is important for determining the subsequent mesothelioma risk of each generation. Consequently, the data indicate that the peak mortality from pleural cancer in most western European countries will be reached in the first decades of the 21st century, i.e. around 2010–2020, when the generations born between 1940 and 1950 will reach the peak age for mesothelioma incidence and mortality. This contrasts with US data, where the peak of pleural cancer incidence has been reached at the end of the 20th century, and reflects a delay in adopting adequate prevention measures since the 1940–1945 generations entered the workforce in the 1960s, when cancer risk from asbestos exposure was already recognized.

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Adenocarcinoma of the lower oesophagus and the gastric cardia has shown a dramatic worldwide increase in incidence over the last 25 years, but the cause is unknown. A large number of drugs have been introduced over this period of time, and it has been suggested that drugs that relax the lower oesophageal sphincter (DRLOS) might be causative, and on the other hand that non-steroidal anti-inflammatory drugs (NSAIDS) may be protective. H2-receptor antagonists (H2RAs) may allow achlorhydric reflux to continue without symptoms, and it is postulated that such asymptomatic reflux is uncontrolled by the usual conservative measures and may lead to increased oesophageal damage. H2RAs were first marketed in 1970 and might be the cause of the observed increase of cardio-oesophageal adenocarcinoma (COA). In a case-control study, the records of 56 subjects who died of COA in the period 1 January 1990 to 31 December 1992 were compared with those of 56 age-/ sex-matched controls who died of myocardial infarction. They were 28 females and 84 males, mean age 69.8 years. The NHS records containing the lifetime prescription history of each subject were retrieved from the health authority. Each prescription was recorded, omitting drugs taken in the two years before diagnosis. Analysis was performed using conditional logistic regression. Other variables, including the use of antacids, steroids, smoking and alcohol, were also examined. Subjects dying of COA were more likely to have consumed H2RAs (relative risk (RR) 7.50, 95% CI 1.33–42.09,P< 0.02). On the other hand, they were less likely to have consumed NSAIDs (RR 0.16, 95% CI 0.03–0.93, P < 0.04) or DRLOS (RR 0.14, 95% CI 0.02–1.0,P= 0.05). This study supports a protective effect from NSAIDs against COA, but the similar effect of DRLOS is related to the increased use of cardiac drugs in the control group. H2RAs appear to have a harmful effect, which may be related to the worldwide increase in COA. However, the trend may have been apparent before cimetidine was widely available, and it is possible that the cause is multi-factorial.

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:0959-8278    

出版商:OVID    

年代:2000

数据来源: OVID