Showing papers by "Dietrich Hoffmann published in 1997"

The changing cigarette, 1950-1995

Abstract: Nicotine is recognized to be the major inducer of tobacco dependence. The smoking of cigarettes as an advantageous delivery system for nicotine, accelerates and aggravates cardiovascular disease, and is causally associated with increased risks for chronic obstructive lung disease, cancer of the lung and of the upper aerodigestive system, and cancer of the pancreas, renal pelvis, and urinary bladder. It is also associated with cancer of the liver, cancer of the uterine cervix, cancer of the nasal cavity, and myeloid leukemia. In 1950, the first large-scale epidemiological studies documented that cigarette smoking induces lung cancer and described a dose-response relationship between number of cigarettes smoked and the risk for developing lung cancer. In the following decades these observations were not only confirmed by several hundreds of prospective and case-control studies but the plausibility of this causal association was also supported by bioassays and by the identification of carcinogens in cigarett...

Identification of Tobacco- Specific Carcinogen in the Cervical Mucus of Smokers and Nonsmokers

Abstract: Background In 1996, an estimated 15,700 new cases of cancer of the uterine cervix and 4,900 deaths from this disease were expected to occur in the United States. In a recent international study, human papillomavirus DNA was found in more than 90% of cervical tumor specimens examined, irrespective of the nationality of the patients from whom the samples were obtained. Although infection with human papillomavirus is the major known risk factor for the development of cervical cancer, it alone is not sufficient. Other etiologic factors that have been associated with this disease include deficiencies in micronutrients, lower socioeconomic status, oral contraceptive use, and cigarette smoking. Several compounds from cigarette smoke (nicotine and its major metabolite, cotinine) have been identified in cervical mucus, and the occurrence of smoking-related DNA damage in the cervical epithelium has been documented. Purpose This investigation was conducted to determine for the first time whether carcinogenic tobacco-specific N-nitrosamines are present in the cervical mucus of cigarette smokers and of nonsmokers (most likely as a result of environmental exposure). Methods Cervical mucus specimens from 15 smokers and 10 nonsmokers were subjected to supercritical fluid extraction with the use of carbon dioxide that contained 10% methanol, and the resultant extracts were analyzed for tobacco-specific nitrosamines by use of a very sensitive method that involved gas chromatography and mass spectroscopy analyses. Results In a total of 16 samples obtained from 15 women who were current smokers (two samples from the same woman), we detected the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) at concentrations that ranged from 11.9 to 115.0 ng/g of mucus. Only one of a total of 10 cervical mucus specimens obtained from 10 women who claimed to be nonsmokers did not contain detectable NNK, and NNK concentrations ranged from 4.1 to 30.8 ng/g of mucus in the specimens from the remaining nine women. The concentrations of NNK in specimens from cigarette smokers were significantly higher than those from nonsmokers (mean +/- standard deviation: 46.9 +/- 32.5 ng/g of mucus versus 13.0 +/- 9.3 ng/g of mucus; two-tailed Student's t test, P = .004). Conclusion The cervical mucus of cigarette smokers contains measurable amounts of the potent carcinogen NNK. This compound represents the first tobacco-specific carcinogen identified in this physiologic fluid of women who smoke cigarettes. The presence of NNK in the cervical mucus of nonsmokers is likely due to environmental exposure or to the fact that some of the subjects in this study may not have revealed that they occasionally smoked cigarettes. Implications The presence of NNK in human cervical mucus further strengthens the association between cervical cancer and tobacco smoking.

Risk of squamous cell carcinoma and adenocarcinoma of the lung in relation to lifetime filter cigarette smoking

Abstract: BACKGROUND Over the past few decades, the incidence of adenocarcinoma (AC) of the lung increased much more rapidly than that of squamous cell carcinoma (SCC) in men and women. During this time period, filter cigarettes with substantially reduced "tar" and nicotine yields in the smoke came to dominate the market. METHODS The risk of SCC and AC in lifelong smokers of filter cigarettes relative to lifelong nonfilter cigarette smokers was assessed in a case-control study performed between 1977 and 1995 with 2292 lung carcinoma patients and 1343 hospital controls who were current smokers. RESULTS Odds ratios (OR) for SCC in male and female subjects who had smoked filter cigarettes exclusively during their lives were slightly reduced relative to lifetime nonfilter cigarette smokers in men (OR = 0.8; 95% confidence interval [CI], 0.5-1.2), and significantly reduced in women (OR = 0.4; 95% CI, 0.2-0.8). No reduction in risk was observed for AC of the lung in men or women. CONCLUSIONS Evidence that the increasing predominance of AC over SCC may be due in part to the reduced risk of SCC (but not AC) associated with lifelong filter cigarette smoking is strongest in women; for men, further studies that include larger numbers of lifetime filter smokers are needed to confirm this finding. A lack of protection against AC from low yield filter cigarettes may result from smokers' "compensating" with deeper and more frequent inhalation, thereby increasing delivery of carcinogens to the peripheral lung. The smoke of modern cigarettes also contains higher concentrations of nitrosamines that primarily produce AC. Cancer 1997; 80:382-8. © 1997 American Cancer Society.

Smoking and pancreatic cancer in men and women.

Abstract: Most studies of smoking and pancreatic cancer have used male subjects or combined men and women together in statistical analyses. There is little information on the relative risk of smoking and pancreatic cancer in women. Because of the high case-fatality rate, many of these studies were also based on information gathered from proxy respondents, in which smoking habits may not be recalled with certainty. A hospital-based study of 484 male and female patients with pancreatic cancer and 954 control subjects was conducted based on direct interviews of incident cases. Compared to never smokers, the odds ratio (OR) for current cigarette smokers was 1.6 [95% confidence interval (CI), 1.1-2.4] for men and 2.3 (95% CI, 1.4-3.5) for women. In women, but not in men, there was a trend in the ORs with years of daily cigarette consumption (P < 0.01). Filter cigarettes offered no protective advantage compared to nonfilter cigarettes. Among men, the OR was 2.1 (95% CI, 1.2-3.8) for pipe/ cigar smokers and 3.6 (95% CI, 1.0-12.8) for tobacco chewers. Tobacco smoke causes pancreatic cancer when inhaled into the lungs. Tobacco juice may also cause pancreatic cancer when ingested or absorbed through the oral cavity. These data suggest that smoking is a cause of pancreatic cancer in women and that the risks for female smokers are comparable to male smokers. Nevertheless, the causes of most pancreatic cancers are unknown.