Pub Date : 1999-12-01DOI: 10.1097/00008469-199912001-00010
Julian Little, J. Faivre
Colorectal cancer is thought to be largely due to dietary factors. There is evidence of familial aggregation of colorectal cancer suggesting that genetic susceptibility may be important in the aetiology of the disease. Only limited data are available comparing risk factors for colorectal cancer with and without a family history. There are arguments suggesting that individuals with a first-degree relative with colorectal cancer are at a greater risk from a diet high in energy than individuals without such a family history. Failure to take into account both genetic and environmental factors can lead to bias in the estimation of disease risk. Genetic polymorphisms interact with dietary intake. A number of associations have been observed between specific genetic polymorphisms and colorectal cancer. But there are inconsistencies between studies, because of methodological limitations in initial studies. Different effects of dietary factors on colorectal cancer risk among individuals with different genotypes or of different effects of a genotype on colorectal cancer risk among individuals with different exposures need to be addressed in future works.
{"title":"Family history, metabolic gene polymorphism, diet and risk of colorectal cancer.","authors":"Julian Little, J. Faivre","doi":"10.1097/00008469-199912001-00010","DOIUrl":"https://doi.org/10.1097/00008469-199912001-00010","url":null,"abstract":"Colorectal cancer is thought to be largely due to dietary factors. There is evidence of familial aggregation of colorectal cancer suggesting that genetic susceptibility may be important in the aetiology of the disease. Only limited data are available comparing risk factors for colorectal cancer with and without a family history. There are arguments suggesting that individuals with a first-degree relative with colorectal cancer are at a greater risk from a diet high in energy than individuals without such a family history. Failure to take into account both genetic and environmental factors can lead to bias in the estimation of disease risk. Genetic polymorphisms interact with dietary intake. A number of associations have been observed between specific genetic polymorphisms and colorectal cancer. But there are inconsistencies between studies, because of methodological limitations in initial studies. Different effects of dietary factors on colorectal cancer risk among individuals with different genotypes or of different effects of a genotype on colorectal cancer risk among individuals with different exposures need to be addressed in future works.","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87070340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-12-01DOI: 10.1097/00008469-199912001-00009
A. Giacosa, S. Franceschi, C. L. Vecchia, A. Favero, R. Andreatta
Epidemiological studies on risk factors for CRC have focused mainly on diet. In any case, the results of these studies show several inconsistencies, except for the beneficial role of high intake of vegetables and, to some lesser extent, of fruit. Weight and height have also been studied, partly because they reflect the balance between energy intake and expenditure in different age periods. Energy intake, body size and physical activity will be reviewed in this paper focusing mostly on recent data coming from Italian, English and Scandinavian studies. Overweight has long been recognized as a risk factor for hormone related and other cancers and this is confirmed not simply from case-control studies but from large cohort studies as well. The major findings of recent Italian studies are that excessive weight at various ages predicts colorectal cancer risk in men while in women, abdominal obesity, as indicated by a high WHR, represents a more reliable risk indicator. If all men could reduce their BMI below 25, about 9% of male colorectal cancer might be avoided in Italy. A decrease of WHR below 0.82 might reduce colorectal cancer in women by 19%. In addition, the epidemiological evidence consistently shows that physical activity reduces the risk of colon cancer. On the contrary, evidence on rectal cancer is less impressive. Some uncertainty still exists in relation to the intensity and duration of physical activity. In conclusion, body size control along all life and physical activity represent important factors to prevent colon cancer and a wide range of chronic conditions. Therefore, strategies to favour these goals through counselling from health-care providers, regulatory changes and programs aimed at individuals and communities should be implemented.
{"title":"Energy intake, overweight, physical exercise and colorectal cancer risk.","authors":"A. Giacosa, S. Franceschi, C. L. Vecchia, A. Favero, R. Andreatta","doi":"10.1097/00008469-199912001-00009","DOIUrl":"https://doi.org/10.1097/00008469-199912001-00009","url":null,"abstract":"Epidemiological studies on risk factors for CRC have focused mainly on diet. In any case, the results of these studies show several inconsistencies, except for the beneficial role of high intake of vegetables and, to some lesser extent, of fruit. Weight and height have also been studied, partly because they reflect the balance between energy intake and expenditure in different age periods. Energy intake, body size and physical activity will be reviewed in this paper focusing mostly on recent data coming from Italian, English and Scandinavian studies. Overweight has long been recognized as a risk factor for hormone related and other cancers and this is confirmed not simply from case-control studies but from large cohort studies as well. The major findings of recent Italian studies are that excessive weight at various ages predicts colorectal cancer risk in men while in women, abdominal obesity, as indicated by a high WHR, represents a more reliable risk indicator. If all men could reduce their BMI below 25, about 9% of male colorectal cancer might be avoided in Italy. A decrease of WHR below 0.82 might reduce colorectal cancer in women by 19%. In addition, the epidemiological evidence consistently shows that physical activity reduces the risk of colon cancer. On the contrary, evidence on rectal cancer is less impressive. Some uncertainty still exists in relation to the intensity and duration of physical activity. In conclusion, body size control along all life and physical activity represent important factors to prevent colon cancer and a wide range of chronic conditions. Therefore, strategies to favour these goals through counselling from health-care providers, regulatory changes and programs aimed at individuals and communities should be implemented.","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81418316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-12-01DOI: 10.1097/00008469-199912001-00011
O. Kronborg, C. Fenger
A review is given on evidence supporting or rejecting the hypothesis of a colorectal adenoma-carcinoma sequence. The majority of studies discuss adenomas from a clinical point of view, but pathology has also been considered in detail, and molecular biology has been touched on. It is concluded the adenoma stage is, most probably, a phase on the way to carcinoma. But it remains to be shown what effect the removal of adenomas will have in the long run on the incidence of colorectal carcinoma.
{"title":"Clinical evidence for the adenoma-carcinoma sequence.","authors":"O. Kronborg, C. Fenger","doi":"10.1097/00008469-199912001-00011","DOIUrl":"https://doi.org/10.1097/00008469-199912001-00011","url":null,"abstract":"A review is given on evidence supporting or rejecting the hypothesis of a colorectal adenoma-carcinoma sequence. The majority of studies discuss adenomas from a clinical point of view, but pathology has also been considered in detail, and molecular biology has been touched on. It is concluded the adenoma stage is, most probably, a phase on the way to carcinoma. But it remains to be shown what effect the removal of adenomas will have in the long run on the incidence of colorectal carcinoma.","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73820434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-12-01DOI: 10.1097/00008469-199912001-00003
L. Martín, M. Assem, F. Piard
Molecular studies have shown that different genetic pathways are involved in the history of colorectal carcinomas. This suggests that a correlation exists between the molecular, clinical and pathological features of tumours. Two large groups can be individualized: the first group is characterized by allelic losses and hyperdiploidy. These LOH (for loss of heterozygosity)-positive tumours represent 80% of colorectal carcinomas. Among them more than two-thirds are located in the distal colon. They have the worst prognosis. The second group has a normal diploid pattern and a phenotypic microsatellite instability without allelic losses. These tumours represent 10-15% of all colorectal carcinomas and about 30% of the right-sided tumours. They are associated with a better prognosis. In the future, it would perhaps be better to classify colorectal carcinomas according to their molecular features rather than to their topographical localizations.
{"title":"Are there several types of colorectal carcinomas? Correlations with genetic data.","authors":"L. Martín, M. Assem, F. Piard","doi":"10.1097/00008469-199912001-00003","DOIUrl":"https://doi.org/10.1097/00008469-199912001-00003","url":null,"abstract":"Molecular studies have shown that different genetic pathways are involved in the history of colorectal carcinomas. This suggests that a correlation exists between the molecular, clinical and pathological features of tumours. Two large groups can be individualized: the first group is characterized by allelic losses and hyperdiploidy. These LOH (for loss of heterozygosity)-positive tumours represent 80% of colorectal carcinomas. Among them more than two-thirds are located in the distal colon. They have the worst prognosis. The second group has a normal diploid pattern and a phenotypic microsatellite instability without allelic losses. These tumours represent 10-15% of all colorectal carcinomas and about 30% of the right-sided tumours. They are associated with a better prognosis. In the future, it would perhaps be better to classify colorectal carcinomas according to their molecular features rather than to their topographical localizations.","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74570722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-12-01DOI: 10.1097/00008469-199912001-00006
S. Olschwang
Colorectal tumorigenesis has been associated with the progressive acquisition of a variety of genomic alterations in neoplastic cells. In 5-10% of cases, a strong family history of cancer suggests a major predisposition, either familial adenomatous polyposis (FAP) or HNPCC syndrome. In 1987, the gene responsible for FAP was localized on chromosome 5q. In 1991, the International Collaborative Group on HNPCC set stringent criteria for the diagnosis of HNPCC, to homogenize families that should be entered in large linkage analyses. In the past five years, five MMR genes could be identified as the site of germline mutations associated with a HNPCC syndrome (MSH2, MLH1, PMS1, PMS2, and MSH6). The TGFbeta RII gene has been found mutated at the germline level in a small number of HNPCC patients. The DNA mismatch repair pathway is essential for the correct maintenance of genetic information. The slippage occurs usually at microsatellite loci and the defect of one MMR gene leads to the accumulation of replication errors in such deficient cells. The tumours that exhibit the highest frequency of RER at microsatellite loci, thus termed RER+, account for 10-15% of all colorectal cancers, and for 92% of those developed in a context of a HNPCC syndrome.
{"title":"Germline mutation and genome instability.","authors":"S. Olschwang","doi":"10.1097/00008469-199912001-00006","DOIUrl":"https://doi.org/10.1097/00008469-199912001-00006","url":null,"abstract":"Colorectal tumorigenesis has been associated with the progressive acquisition of a variety of genomic alterations in neoplastic cells. In 5-10% of cases, a strong family history of cancer suggests a major predisposition, either familial adenomatous polyposis (FAP) or HNPCC syndrome. In 1987, the gene responsible for FAP was localized on chromosome 5q. In 1991, the International Collaborative Group on HNPCC set stringent criteria for the diagnosis of HNPCC, to homogenize families that should be entered in large linkage analyses. In the past five years, five MMR genes could be identified as the site of germline mutations associated with a HNPCC syndrome (MSH2, MLH1, PMS1, PMS2, and MSH6). The TGFbeta RII gene has been found mutated at the germline level in a small number of HNPCC patients. The DNA mismatch repair pathway is essential for the correct maintenance of genetic information. The slippage occurs usually at microsatellite loci and the defect of one MMR gene leads to the accumulation of replication errors in such deficient cells. The tumours that exhibit the highest frequency of RER at microsatellite loci, thus termed RER+, account for 10-15% of all colorectal cancers, and for 92% of those developed in a context of a HNPCC syndrome.","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76081183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-02-01DOI: 10.1097/00008469-199902000-00002
M. Moore, H. Tsuda
Advances in identification of the risk factors for cancer development in different organs imply more effective screening for early malignancies. The associated increase in the predictive value, as well as the introduction of procedures with high sensitivity and specificity, provide promise that early intervention will result in a marked decrease in the mortality and morbidity due to a wide range of major cancers. Furthermore, a variety of methods are now available to detect lesions at a sufficiently early stage for curative surgery to be attempted. However, for the full promise to be realized, it is of paramount importance that both physicians and the public at large are fully aware of the potential benefits.
{"title":"Cancer screening: an educational challenge?","authors":"M. Moore, H. Tsuda","doi":"10.1097/00008469-199902000-00002","DOIUrl":"https://doi.org/10.1097/00008469-199902000-00002","url":null,"abstract":"Advances in identification of the risk factors for cancer development in different organs imply more effective screening for early malignancies. The associated increase in the predictive value, as well as the introduction of procedures with high sensitivity and specificity, provide promise that early intervention will result in a marked decrease in the mortality and morbidity due to a wide range of major cancers. Furthermore, a variety of methods are now available to detect lesions at a sufficiently early stage for curative surgery to be attempted. However, for the full promise to be realized, it is of paramount importance that both physicians and the public at large are fully aware of the potential benefits.","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1999-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81843061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1998-02-01DOI: 10.1097/00008469-199802001-00071
S. Shering, Zbar Ap, M. Moriarty, E. McDermott, N. O’higgins, P. Smyth
We have investigated the controversial association between diseases of the thyroid gland and breast carcinoma using methodology which allows positive exclusion of cases of breast disease from control groups and the detection of subclinical alterations in thyroid volume using high resolution ultrasonography, thus addressing the deficiencies of earlier studies. Whereas the prevalence of hyperthyroidism and hypothyroidism in patients with breast carcinoma and in healthy controls without clinical evidence of breast disease was similar, non-toxic goitre was more than twice as common in the breast carcinoma patients. Thyroid volumes were also significantly higher in breast carcinoma patients than in controls; using World Health Organisation criteria, 45.5% of breast carcinoma patients had thyroid enlargement compared with only 10.5% of controls. Finally, antithyroid peroxidase autoantibodies were twice as common in breast cancer patients than in controls. These findings provide clear evidence of a relationship between thyroid disease and breast carcinoma, although the mechanisms underlying this relationship require further study, future studies of breast cancer risk factors should therefore include assessment of thyroid function, antibody status and volume.
{"title":"Thyroid disorders and breast cancer.","authors":"S. Shering, Zbar Ap, M. Moriarty, E. McDermott, N. O’higgins, P. Smyth","doi":"10.1097/00008469-199802001-00071","DOIUrl":"https://doi.org/10.1097/00008469-199802001-00071","url":null,"abstract":"We have investigated the controversial association between diseases of the thyroid gland and breast carcinoma using methodology which allows positive exclusion of cases of breast disease from control groups and the detection of subclinical alterations in thyroid volume using high resolution ultrasonography, thus addressing the deficiencies of earlier studies. Whereas the prevalence of hyperthyroidism and hypothyroidism in patients with breast carcinoma and in healthy controls without clinical evidence of breast disease was similar, non-toxic goitre was more than twice as common in the breast carcinoma patients. Thyroid volumes were also significantly higher in breast carcinoma patients than in controls; using World Health Organisation criteria, 45.5% of breast carcinoma patients had thyroid enlargement compared with only 10.5% of controls. Finally, antithyroid peroxidase autoantibodies were twice as common in breast cancer patients than in controls. These findings provide clear evidence of a relationship between thyroid disease and breast carcinoma, although the mechanisms underlying this relationship require further study, future studies of breast cancer risk factors should therefore include assessment of thyroid function, antibody status and volume.","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1998-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78945358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1997-10-01DOI: 10.1097/00008469-199710000-00047
C. Vecchia, A. Tavani
A large body of evidence indicates that high intakes of fruit and vegetables are associated with a reduced risk of cancer at several sites. The association is generally most marked for epithelial cancers, apparently stronger for those of the digestive and respiratory tracts, and somewhat weaker for hormone-related cancers. The relationship between frequency of consumption of vegetables and fruit and cancer risk was analysed using data from a series of case-control studies conducted in northern Italy since 1983. The relative risks (RRs) for most common neoplasms ranged from 0.2 to 0.5 for the highest compared with the lowest tertile of vegetable intake. Protective effects were highest for epithelial neoplasms, but were also observed for hormone-related neoplasms. Fruit was related to reduced RRs for cancers of the oral cavity and pharynx, oesophagus, stomach, larynx, as well as of the urinary tract. There was a specific and consistent pattern of protection by tomatoes, a typical Mediterranean food, with RRs between 0.4 and 0.7, most notably for gastrointestinal neoplasms. No significant association was observed between fruit and vegetable consumption and non-epithelial lymphoid neoplasms. For digestive tract cancer, population attributable risks for low intake of fresh vegetables and fruit ranged from 15 to 40% of all cases in this Mediterranean population. Combined with tobacco and alcohol, the population attributable risks exceeded 85% for men and 55% for women for upper digestive and respiratory tract neoplasms. Thus, from a public health viewpoint, epidemiological evidence indicates that a substantial reduction in epithelial cancer risk can be obtained by increasing fruit and vegetable consumption.
{"title":"Fruit and vegetables, and human cancer.","authors":"C. Vecchia, A. Tavani","doi":"10.1097/00008469-199710000-00047","DOIUrl":"https://doi.org/10.1097/00008469-199710000-00047","url":null,"abstract":"A large body of evidence indicates that high intakes of fruit and vegetables are associated with a reduced risk of cancer at several sites. The association is generally most marked for epithelial cancers, apparently stronger for those of the digestive and respiratory tracts, and somewhat weaker for hormone-related cancers. The relationship between frequency of consumption of vegetables and fruit and cancer risk was analysed using data from a series of case-control studies conducted in northern Italy since 1983. The relative risks (RRs) for most common neoplasms ranged from 0.2 to 0.5 for the highest compared with the lowest tertile of vegetable intake. Protective effects were highest for epithelial neoplasms, but were also observed for hormone-related neoplasms. Fruit was related to reduced RRs for cancers of the oral cavity and pharynx, oesophagus, stomach, larynx, as well as of the urinary tract. There was a specific and consistent pattern of protection by tomatoes, a typical Mediterranean food, with RRs between 0.4 and 0.7, most notably for gastrointestinal neoplasms. No significant association was observed between fruit and vegetable consumption and non-epithelial lymphoid neoplasms. For digestive tract cancer, population attributable risks for low intake of fresh vegetables and fruit ranged from 15 to 40% of all cases in this Mediterranean population. Combined with tobacco and alcohol, the population attributable risks exceeded 85% for men and 55% for women for upper digestive and respiratory tract neoplasms. Thus, from a public health viewpoint, epidemiological evidence indicates that a substantial reduction in epithelial cancer risk can be obtained by increasing fruit and vegetable consumption.","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84457727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1997-06-01DOI: 10.1097/00008469-199706000-00009
C. Gilbert
{"title":"Cloning of sheep: a possible technique for reprogramming ageing mechanisms.","authors":"C. Gilbert","doi":"10.1097/00008469-199706000-00009","DOIUrl":"https://doi.org/10.1097/00008469-199706000-00009","url":null,"abstract":"","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73572707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1997-06-01DOI: 10.1097/00008469-199706000-00003
A. Tricker
Based on recent analytical data, total human exogenous exposure to N-nitrosamines is estimated to be 1.10 mumol/day; the major exposure sources are the diet (0.79 mumol/may, 80-120 micrograms/day; 72%), occupational exposure (0.15-0.30 mumol/day; 25%), cigarette smoking (0.02 mumol/day, 3.4 micrograms/day; 2%), and miscellaneous minor sources, including pharmaceutical products, cosmetics, indoor and outdoor air (0.001 mumol/day, 0.1 micrograms/day; 1%). Excretion of apparent total N-nitroso compounds (ATNC) in healthy adults is estimated to be 1.30 +/- 1.05 mumol/day in urine and between 1.56 +/- 1.56 and 3.17 +/- 2.58 mumol/day in faeces. The excretion of volatile N-nitrosamines (N-nitrosodimethylamine), and N-nitrosamine acids and their derivatives (N-nitrososarcosine, N-nitrosoproline, N-nitrosothiazolidine-4-carboxylic acid and N-nitroso-2-methylthiazoline-4-carboxylic acid) accounts for approximately 0.03% and 16.0% of urinary ATNC, respectively. 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol and its O-glucuronide conjugate, two metabolites of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone present in urine of smokers, account for 0.2% of the urinary ATNC response; < 1.5 of the excretion of currently identified N-nitroso compounds in urine. The remaining N-nitroso compounds excreted in urine and those present in faeces are still unidentified. A crude mass balance between exogenous exposure and excretion in urine and faeces indicates that 45-75% of the total human exposure to N-nitroso compounds results through in vivo formation.
{"title":"N-nitroso compounds and man: sources of exposure, endogenous formation and occurrence in body fluids.","authors":"A. Tricker","doi":"10.1097/00008469-199706000-00003","DOIUrl":"https://doi.org/10.1097/00008469-199706000-00003","url":null,"abstract":"Based on recent analytical data, total human exogenous exposure to N-nitrosamines is estimated to be 1.10 mumol/day; the major exposure sources are the diet (0.79 mumol/may, 80-120 micrograms/day; 72%), occupational exposure (0.15-0.30 mumol/day; 25%), cigarette smoking (0.02 mumol/day, 3.4 micrograms/day; 2%), and miscellaneous minor sources, including pharmaceutical products, cosmetics, indoor and outdoor air (0.001 mumol/day, 0.1 micrograms/day; 1%). Excretion of apparent total N-nitroso compounds (ATNC) in healthy adults is estimated to be 1.30 +/- 1.05 mumol/day in urine and between 1.56 +/- 1.56 and 3.17 +/- 2.58 mumol/day in faeces. The excretion of volatile N-nitrosamines (N-nitrosodimethylamine), and N-nitrosamine acids and their derivatives (N-nitrososarcosine, N-nitrosoproline, N-nitrosothiazolidine-4-carboxylic acid and N-nitroso-2-methylthiazoline-4-carboxylic acid) accounts for approximately 0.03% and 16.0% of urinary ATNC, respectively. 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol and its O-glucuronide conjugate, two metabolites of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone present in urine of smokers, account for 0.2% of the urinary ATNC response; < 1.5 of the excretion of currently identified N-nitroso compounds in urine. The remaining N-nitroso compounds excreted in urine and those present in faeces are still unidentified. A crude mass balance between exogenous exposure and excretion in urine and faeces indicates that 45-75% of the total human exposure to N-nitroso compounds results through in vivo formation.","PeriodicalId":11950,"journal":{"name":"European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83804017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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