Biomedical subjects

P Boffetta

Publications and source records attributed to P Boffetta.

At least 163 records · Page 9Linked to original sources

PubMed1998

Hard liquor drinking is associated with higher risk of cancer of the oral cavity and pharynx than wine drinking. A case-control study in Uruguay.

In order to examine the relationship between pure drinkers of alcoholic beverages and cancer of the oral cavity and pharynx, a case-control study was conducted in Uruguay between 1992 and 1996. 471 cases and 471 controls, admitted for diagnosis or treatment in the four major hospitals in Montevideo, were considered eligible for the study. Pure hard liquor drinking was associated with an increased risk of 3.6 (95% confidence limit (CL) 2.1-6.2), whereas pure wine drinking showed an odds ratio (OR) of 2.1 (95% CL 1.3-3.3). When pure hard liquor drinkers were compared with pure wine drinkers, the OR for pure liquor drinkers was 1.7 (95% CL 1.1-2.7). Furthermore, the risk associated with pure hard liquor drinking was analysed by subsite, and the highest odds ratios were observed for oral cavity cancer. Further studies should be carried out in order to replicate these findings in other populations.

Adult↗

PubMed1998

Smoking patterns and cancer of the oral cavity and pharynx: a case-control study in Uruguay.

A case-control study of cancer of the oral cavity and pharynx was conducted in Uruguay, between 1992 and 1996. 425 patients microscopically diagnosed with squamous cell carcinoma of the oral cavity and pharynx were frequently matched on age, residence, and urban/rural status with 427 hospitalised controls. The study was restricted to males. Smokers of black tobacco cigarettes were associated with an increased risk of 12.1 (95% confidence interval (CI) 7.6-19.4), when compared with non-smokers after fitting a model which included the matching variables, birthplace, education, and total alcohol consumption. Lifelong smokers of hand-rolled cigarettes displayed an odds ratio (OR) of 8.7 (95% CI 5.6-13.4), compared with non-smokers. When smokers were excluded from the calculations, the OR for smokers of black tobacco cigarettes was 3.0 (95% CI 2.0-4.6), compared with smokers of blond tobacco cigarettes, after controlling for the same variables mentioned above, plus pack-years, years since stopping, and filter use. Hand-rolling appears to be less important than smoking black tobacco in this study (OR 1.6, 95% CI 0.9-2.5). Thus, smoking black tobacco cigarettes appears to be an important habit in oral and pharyngeal carcinogenesis.

Adult↗

PubMed1998

Reliability of data on smoking habit and coffee drinking collected by personal interview in a hospital-based case-control study.

A study on the reliability of information on smoking habits and coffee drinking collected via interview was conducted among 500 subjects enrolled in a case-control study on bladder cancer in Brescia, North Italy. A total of 215 cases (incident and prevalent) and 285 controls were interviewed personally in the hospital setting by a first interviewer, and then re-interviewed by telephone by either the same interviewer or another one. Agreement between the first and second interview was evaluated using the kappa statistic and the intra-class correlation coefficient and via multiple logistic regression modelling. No important differences in reliability were found according to sex, education or case/control status, while agreement was better among subjects below 65 than among older ones, and among incident than prevalent cases. A slightly better agreement was found among subjects interviewed twice by the same interviewer than those interviewed by two different individuals, which may reflect the presence of inter-observer reliability for the latter. Overall, these results show a very high reliability of data on smoking and a fairly high reliability regarding coffee drinking as collected through face-to-face interviews.

Adult↗

PubMed1998

Tobacco smoking and alcohol drinking as risk factors for stomach cancer: a case-control study in Uruguay.

OBJECTIVES: To estimate the risk of stomach cancer associated with alcohol drinking and tobacco smoking in Uruguayan men. METHODS: A case-control including 331 cases and 622 controls was conducted in Montevideo, Uruguay, during the period 1992-96. The study was restricted to men, and both cases and controls were patients admitted to the major four hospitals in Montevideo. Response rates were high and similar for both series (92.8 for cases and 92.6 percent for controls). Controls were frequency-matched to cases on age and residence, and patients with conditions related a priori to tobacco smoking and alcohol drinking were considered ineligible for the study. All patients were interviewed shortly after admission using a structured questionnaire by two trained social workers. Relative risks, approximated by the odds ratios (OR), were estimated by unconditional logistic regression in models including major potential confounders. RESULTS: Smoking duration was associated with an increased risk of 2.2 for smokers of more than 50 years, with a significant dose-response pattern, after controlling for major confounders. Quitters of more than 15 years displayed an OR of 1.1, very close to the risk of never-smokers. A younger age at having started smoking was associated with an increased risk, whereas pack-years of cigarettes showed a significant dose-response. Also, alcohol drinking (particularly hard liquor and beer) was associated with an OR of 2.4 (95 percent confidence interval = 1.5-3.9), after controlling for the effect of tobacco, vegetables, and other types of alcohol beverages. CONCLUSIONS: These findings add further support to the role of tobacco and alcohol in gastric carcinogenesis.

Adult↗

PubMed1998

Cancer occurrence among European mercury miners.

OBJECTIVES: To study the carcinogenicity of inorganic mercury in humans. METHODS: We studied the mortality from cancer among 6784 male and 265 female workers of four mercury mines and mills in Spain, Slovenia, Italy and the Ukraine. Workers were employed between the beginning of the century and 1990; the follow-up period lasted from the 1950s to the 1990s. We compared the mortality of the workers with national reference rates. RESULTS: Among men, there was no overall excess cancer mortality; an increase was observed in mortality from lung cancer (standardized mortality ratio [SMR] 1.19, 95 percent confidence interval [CI] 1.03-1.38) and liver cancer (SMR 1.64, CI 1.18-2.22). The increase in lung cancer risk was restricted to workers from Slovenia and the Ukraine: no relationship was found with duration of employment or estimated mercu ry exposure. The increase in liver cancer risk was present both among miners and millers and was stronger in workers from Italy and Slovenia: there was a trend with estimated cumulative exposure but not with duration of employment, and the excess was not present in a parallel analysis of cancer incidence among workers from Slovenia. No increase was observed for other types of cancer, including brain and kidney tumours. Among female workers (Ukraine only), three deaths occurred from ovarian cancer, likely representing an excess. CONCLUSIONS: Exposure to inorganic mercury in mines and mills does not seem strongly associated with cancer risk, with the possible exception of liver cancer; the increase in lung cancer may be explained by co-exposure to crystalline silica and radon.

Carcinogens↗

PubMed1998

Cancer mortality among Moscow shoe workers exposed to chloroprene (Russia).

OBJECTIVES: To assess the risk of cancer among workers of a Moscow (Russia) shoe factory exposed to chloroprene (2-chloro-1,3-butadiene) (CP). METHODS: This is a retrospective cohort mortality study among 5,185 shoe manufacturing workers employed between 1940 and 1976, and followed from 1979 through 1993. Exposure to CP was assessed by linking the job history with industrial hygiene data. We calculated standardized mortality ratios (SMR) using the Moscow population as reference, and conducted an internal comparison analysis based on Poisson regression modeling. RESULTS: For the entire cohort, all-cause mortality was close to expectation and all-cancer mortality was increased. There was an increase in the mortality from liver cancer (SMR = 2.4, 95 percent confidence interval [CI] = 1.1-4.3), kidney cancer (SMR = 1.8, CI = 0.9-3.4), and leukemia (SMR = 1.9, CI = 1.0-3.3). Mortality from liver cancer and leukemia was associated with various indicators of CP exposure. A similar, although less consistent, pattern was found for kidney cancer mortality; while for the remaining neoplasms, no association was suggested with CP exposure. CONCLUSIONS: The association between CP exposure and risk of leukemia may be due to concomitant exposure to benzene. The results for liver cancer point towards a carcinogenic effect of CP.

Cause of Death↗

PubMed1998

Lung cancer mortality among European rock/slag wool workers: exposure-response analysis.

OBJECTIVES: The purpose was to analyze the relationship between semi-quantitative indices of exposure to manmade vitreous fibers and lung cancer mortality among European rock/slag wool (RSW) workers. METHODS: The study population comprised 9,603 male workers employed in RSW production in seven factories in Denmark, Norway, Sweden, and Germany, followed up for mortality as of 1990-91. Estimates of past exposure to respirable fibers were used to calculate cumulative exposure with a 15-year lag and maximum annual exposure based on employment history up to 1977. Rate ratios were estimated via multivariate Poisson regression, adjusting for country, age, calendar year, time since first employment, and employment status. RESULTS: A total of 159 lung cancer deaths were included in the analysis of which 97 among workers with more than one year of employment. We found nonstatistically significant trends in lung cancer risk according to cumulative exposure. Relative risks (RR) in the four quartiles were 1.0 (reference), 1.3 (95 percent confidence interval [CI] = 0.8-2.4), 1.2 (CI = 0.7-2.1), and 1.5 (CI = 0.7-3.0, P test for trend = 0.4). When workers with less than one year of employment were excluded, there was no increased risk; the RRs in the four quartiles were 1.0, 0.9 (CI = 0.4-2.0), 0.8 (CI = 0.3-1.9), and 1.0 (CI = 0.4-2.7). No trend was present according to maximum annual exposure. The results were not consistent among countries. CONCLUSIONS: We found a positive association between exposure to respirable fibers and lung cancer mortality. However, the lack of statistical significance, the dependence of the results on inclusion of short-term workers, the lack of consistency among countries, and the possible correlation between exposure to respirable fibers and to other agents reduce the weight of such evidence.

Adult↗

PubMed1998

A European validation study of smoking and environmental tobacco smoke exposure in nonsmoking lung cancer cases and controls.

OBJECTIVES: The purpose of this study was to validate, in a case-control study, the reporting by lung cancer cases and controls of their own lifetime smoking habits and of the smoking habit of the spouse. METHODS: In a multicenter (Sweden, Spain, Italy) case-control study of environmental tobacco smoke (ETS) and lung cancer, subjects were screened by repeated probing to exclude regular smokers of one cigarette/day or more for one year or more, and to quantify any occasional smoking. We then performed a short validation interview with next-of-kin in three centers. RESULTS: Only five of 408 index subjects who had never smoked regularly (1.7 percent) were reported by next-of-kin to be former regular smokers. These subjects had a cumulative lifetime consumption of cigarettes below 1.1 pack years. Among 351 subjects with quantitative smoking information from both sources who reported ever smoking 400 cigarettes or less (the definition of never-smoker used in the multicenter ETS study), nine subjects (2.6 percent) had smoked more than this amount occasionally according to next-of-kin. Misclassification was not higher for cases than controls. Relative risks for lung cancer associated with indicators of ETS exposure were not substantially altered by excluding the nine possibly misclassified subjects. The reports from 223 pairs of index subjects and next-of kin regarding the cumulative amount smoked by the spouse agreed quite well (Spearman's rank correlation 0.75 for reported smokers, 0.92 for all subjects). Only one index subject failed to report a spouse who had smoked regularly (99 percent sensitivity). CONCLUSIONS: Smoking status and exposure to spousal ETS as reported by lung cancer cases and controls agreed strongly with reports by next-of-kin. Overall, our results suggest that bias from smoker misclassification is likely to be insignificant, and they contribute to the evidence linking exposure to ETS with an increased risk of lung cancer.

Adult↗

PubMed1998

Schistosomiasis and the risk of bladder cancer in Alexandria, Egypt.

The relationship between history of schistosomiasis and bladder cancer risk was investigated using data from a case-control study conducted between January 1994 and July 1996 in Alexandria, Egypt. Cases were 190 subjects with incident, histologically confirmed invasive cancer of the bladder, and controls were 187 subjects admitted to hospital for acute, non-neoplastic, non-urinary tract conditions. Eighty-six cases (45%) vs 69 controls (37%) reported a history of urinary schistosomiasis. The corresponding multivariate odds ratio (OR) of bladder cancer -- after allowance for age, sex, education, smoking, other urinary infections and high-risk occupations -- was 1.72 (95% confidence interval (CI) 1.0-2.9). The ORs were 0.22 (95% CI 0.1-0.4) for intestinal schistosomiasis and 0.32 (95% CI 0.1-1.9) for schistosomiasis of other types. The OR for urinary schistosomiasis was higher in subjects who were younger at first diagnosis (OR of 3.3 for <15 years) and in those with a long time since first diagnosis (OR of 3.0 for > or = 35 years). The ORs were 15.8 for male ever-smokers with a history of urinary schistosomiasis, compared with never-smokers without such a history, and 3.2 for men ever-infected with urinary Schistosoma haematobium and ever-employed in high-risk occupations, compared with those never-infected and with no high-risk occupational history. This study confirms that clinical history of urinary schistosomiasis is significantly, but modestly, associated with increased bladder cancer risk, explaining some 16% of bladder cancer cases in this Egyptian population.

Adult↗

PubMed1998

Dietary nitrosamines, heterocyclic amines, and risk of gastric cancer: a case-control study in Uruguay.

To study the effects of dietary chemicals like nitrosodimethylamine and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine, resulting from the cooking method of red meat, on gastric carcinogenesis, a case-control study was conducted in Uruguay, a country with areas of high rates of gastric cancer. The study involved 340 cases and 698 controls, who were interviewed between January 1993 and December 1996. Dietary nitrosodimethylamine was associated with an increased risk of gastric cancer [odds ratio (OR) = 3.6, 95% confidence interval (CI) = 2.4-5.5], whereas dietary 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (a potent mutagen derived from the frying and broiling of red meat) showed an OR of 3.9 (95% CI = 2.3-6.4). Both chemicals displayed independent effects, and its interaction followed a multiplicative model with an elevated OR of 12.7 (95% CI = 7.7-21.2). These results suggest that salted and barbecued meat, frequent items in the Uruguayan diet, and the resulting chemicals from the cooking methods of both types of meat are significantly associated with a high risk of stomach cancer.

Adult↗

PubMed1998

Cisplatin-DNA adducts and protein-bound platinum in blood of testicular cancer patients.

DNA adducts formed by cisplatin [cis-diamminedichloroplatinum(II)] were measured in blood samples from 48 testicular cancer patients treated in four centers in Europe during four to six cycles with cisplatin infusions on five successive days (total samples, 112). Total protein-bound platinum (Pt) in blood was also measured (total samples, 84). The mean on the main DNA adduct, cis-Pt(NH3)2d(pGpG) (Pt-GG), was 0.75 fmol/microg DNA [standard deviation (SD) = 0.66] on the first day of the first cycle, increased after the infusion at day 5 of the cycle (mean 1.74 fmol/microg DNA, SD = 0.90) and decreased on the following day (mean 1.09 fmol/microg DNA, SD = 0.62). In subsequent cycles, there was a tendency to an increase in the mean Pt-GG levels. The values of protein-bound Pt in blood showed little reduction between day 5 and 6 of each cycle, and a stable increase during the course of the therapy. Strong correlations were seen between day 1, 5 and 6 of the first cycle for both Pt-GG and protein-bound Pt in blood. A strong correlation (r = 0.62, p < 0.001, 69 pairs) was found between the levels of Pt-GG and protein-bound Pt. Only two patients relapsed during the follow-up; therefore, the analysis of the association between Pt-GG levels and response to therapy was not informative. The results of this study suggest that DNA adducts formed by cisplatin at the beginning of chemotherapy are predictive of values found during later days and cycles, and that the value of protein-bound Pt in blood is predictive of the value of DNA adducts.

Adult↗

PubMed1998

Mortality of short-term workers in two international cohorts.

The purpose of this study was to compare the pattern of mortality of blue-collar workers employed less and more than 1 year in the man-made vitreous fiber (MMVF) and the reinforced plastic industries, the latter group being exposed to styrene. We conducted an analysis among 21,784 workers with less than 1 year of employment (short-term workers) and 19,117 workers with 1 or more years of employment (long-term workers) employed in eight European countries. We conducted analyses based on external as well as internal comparisons. In both cohorts, the standardized mortality ratio for all causes among short-term workers was approximately 40% higher, compared with that for longer-term workers. In internal comparisons, the difference was reduced to 9% in the MMVF cohort and 11% in the styrene cohort. Workers with less than 1 month of employment displayed an increased mortality in both cohorts and in most countries. The increased mortality among short-term workers was not concentrated shortly after they quit employment. In both cohorts, short-term workers had a higher mortality from external causes, while little difference was seen in mortality from ischemic heart disease and malignant neoplasms. Although extra-occupational factors may contribute to increase the mortality of short-term workers and, in particular, of those employed for less than 1 month, the difference observed in analyses adjusted for characteristics of employment suggested a relatively small difference in mortality from most causes.

Adult↗

PubMed1998

Cancer risk in the rubber industry: a review of the recent epidemiological evidence.

OBJECTIVES: To examine the recent epidemiological evidence on cancer risk among workers in the rubber industry. METHODS: Epidemiological studies published after the last detailed review by the International Agency for Research on Cancer (IARC) in 1982 were reviewed. 12 cohort studies in nine countries that examined distinct populations of workers in the rubber industry, seven industry based nested case-control studies, 48 community based case-control studies in 16 countries, and 23 studies based on administrative data that reported risks for employment in the rubber industry were identified. RESULTS: Excess risks of bladder cancer, lung cancer, and leukaemia were found in most studies, with risks above 1.5 in about half of the studies. A moderate excess risk for laryngeal cancer was consistent across studies. Excess risks were found in a few studies for cancers of the oesophagus, stomach, colon, liver, pancreas, skin, prostate, kidney, brain, and thyroid, and for malignant lymphoma and multiple myeloma, but overall results were not consistent for these neoplasms. CONCLUSIONS: Magnitude of the observed risks varied considerably between studies, but overall the findings indicate the presence of a widespread moderate increased cancer risk among rubber workers. The most consistent results were for bladder, laryngeal, and lung cancer and for leukaemia. Excess risks were also found for other neoplasms but an evaluation of the consistency of the findings is difficult because of the possible selective reporting of results. Recent studies do not provide information associating specific exposures with cancer risk. The preventive measures taken in the rubber industry in recent years may decrease risks, but this has not been documented yet in epidemiological studies.

Case-Control Studies↗

PubMed1998

Exposure to dioxin and nonneoplastic mortality in the expanded IARC international cohort study of phenoxy herbicide and chlorophenol production workers and sprayers.

The authors studied noncancer mortality among phenoxyacid herbicide and chlorophenol production workers and sprayers included in an international study comprising 36 cohorts from 12 countries followed from 1939 to 1992. Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin or higher chlorinated dioxins (TCDD/HCD) was discerned from job records and company questionnaires with validation by biologic and environmental measures. Standard mortality ratio analyses suggested a moderate healthy worker effect for all circulatory diseases, especially ischemic heart disease, among both those exposed and those not exposed to TCDD/HCD. In Poisson regression analyses, exposure to TCDD/HCD was not associated with increased mortality from cerebrovascular disease. However, an increased risk for circulatory disease, especially ischemic heart disease (rate ratio [RR] 1.67, 95% confidence interval [Cl] 1.23-2.26) and possibly diabetes (RR 2.25, 95% Cl 0.53-9.50), was present among TCDD/HCD-exposed workers. Risks tended to be higher 10 to 19 years after first exposure and for those exposed for a duration of 10 to 19 years. Mortality from suicide was comparable to that for the general population for all workers exposed to herbicides or chlorophenols and was associated with short latency and duration of exposure. More refined investigations of the ischemic heart disease and TCDD/HCD exposure association are warranted.

Adult↗

PubMed1998

Environmental risk factors of breast cancer.

Breast cancer is women's most ubiquitous cancer. The role of dietary factors is controversial, but there is limited evidence for such occupational risk factors as employment in the pharmaceutical industry and as a beautician. Ionizing radiation probably increases the risk. Exposure to chlorinated hydrocarbon pesticides, chlorinated solvents, and polychlorinated biphenyls may be risk factors, although the evidence is insufficient. Data on low-frequency electromagnetic fields are inconclusive. Tobacco smoking may be a risk factor, but the effect may depend on N-acetyltransferase 2 genetic polymorphisms. There are yet unidentified determinants, probably environmental, that may act via estrogenic activity or through other mechanisms. The etiology may vary according to the joint estrogen and progesterone receptor status of the tumor. P53 mutation frequency varies considerably in breast cancer populations, which may reflect variation in exogenous exposures. Epidemiology research on breast cancer needs to consider subtypes of the disease, lifetime exposure assessment, host susceptibility, and adjustment for reproductive and menstrual history.

Breast Neoplasms↗

PubMed1998

Occupational risk factors of lung cancer in São Paulo, Brazil.

OBJECTIVES: This study estimated the risk of occupational exposure for lung cancer in the metropolitan region of São Paulo, the largest urbanized and industrialized area in Brazil. METHODS: In this hospital-based case-referent study of 398 cases and 860 referents, the cases were matched to referents according to age, gender, and hospital and personally interviewed for information on lifetime job history, smoking habits, passive smoking exposure, cancer in relatives, socioeconomic status, and migratory history. The analysis concerned industrial titles and occupational categories. With the use of a job-exposure matrix, exposure to asbestos, polynuclear aromatic hydrocarbons, arsenic, dust, nickel and chromium was assessed. RESULTS: For the men in the 56 industrial and 122 occupational categories examined, an excess risk of lung cancer was found in the machinery industry [odds ratio (OR) 1.62, 95% confidence interval (95% CI) 1.02-2.55). In pottery manufacturing the risk (OR 2.21, 95% CI 1.00-4.87) was increased for workers exposed > or = 10 years (OR 6.43, 95% CI 1.12-37.01). Textile workers employed for > or = 10 years with a latency of > or = 40 years had an elevated risk (OR 21.93, 95% CI 1.96-245.0). In the analysis using the job-exposure matrix no risk was detected for the specific lung cancer carcinogens examined. For the women, no significantly elevated risk was observed. CONCLUSIONS: The results of this study revealed risks of lung cancer for men in the machinery industry and for pottery and textile workers with long-term exposure.

Adult↗

PubMed1998

Occurrence, trends and environment etiology of pancreatic cancer.

This review summarizes data on the occurrence, the trends, and the life-style, environmental, occupational and genetic determinants of pancreatic cancer. Epidemiologic evidence implicates tobacco smoking as one cause. The evidence regarding alcohol consumption is inconsistent. Although both positive and inconclusive findings are encountered, the bulk of the evidence on coffee consumption is negative. Fat intake is linked with obesity and diabetes mellitus, which are risk factors for pancreatic cancer. Fruit and vegetable consumption appears to be protective. No occupational or environmental agent has been confirmed to increase the risk, but epidemiologic evidence is inconsistent, Little is known about the role of genetic polymorphisms of metabolic enzymes in pancreas carcinogenesis. Pancreatic cancer shows high rates of mutations of Ki-ras and losses or mutations of tumor suppressor genes (p53, p16INK4A, and SMAD4/DPC-4). Ki-ras mutations have been associated with life-style factors in relation to pancreatic cancer, but the evidence is still scant and inconsistent.

Female↗

PubMed1998

Epidemiology of occupational and environmental risk factors related to ovarian cancer.

This paper reviews articles published during 1970-1997 from 48 epidemiologic studies on occupational and environmental risk factors of ovarian cancer. Current evidence is characterized by poorly focused data for occupational and environmental agents, vulnerability to biases, and an almost complete lack of quantitative exposure-response data. The moderate amount of data on nurses, teachers, professionals, dry cleaning employees, women in agriculture, the pharmaceutical industry, pharmacists, waitresses, and cooks show very little, if any, evidence of excess risk. Hairdressers, beauticians, and women employed in the printing industry may be at increased risk, but the data are insufficient for strong conclusions. Some case-referent studies suggest a modest-to-moderate excess in association with genital talc application. Few high-quality studies have been carried out, and no chemical agents have been studied extensively, with the exception of exposure to talc. Ovarian cancer may have occupational and environmental etiologies intertwined with cultural, behavioral, and life-style factors and genetic susceptibility, but current knowledge is insufficient to quantify occupational and environmental etiologies reliably. Well-designed analytic epidemiologic studies with sufficient power are needed.

Adolescent↗