Risk of lung cancer among cigarette smokers in relation to tumor location

Abstracts/Lung Cancer 12 (1995) 265-329

statistics. Most prominent are those working with asbestos. I&h year about 250 asbestos-associated bronchial carcinomas and 400 mcsotheliomas are recognized and compensated, the tendency is increasing. Because of the long latency time, the frequency peak will probably be reached in about 15 years in spite of the prohibition of asbestos usage. The second place is probably taken by malignomas among the underground uranium mine workers in Thuringia and Saxony (SDAG Wismut). Next come bronchial carcinomas with silicosis (carcinoma in sear tissue) after exposure to chromium(VI) and arsenic compounds as well as various other chemicals and metals. Dose-activity relationships am significant for all occupational carcinogenic agents, as there are also often syneancerogenic influences (especially smoking), From the data on previous loading, high risk groups, for example, among the insulation workers exposed to asbestos or uranium miners in the so-called ‘wild years’, can be defined. A suitable screening method for the detection of bronchopulmonary tumors in the early stages has not yet been established. Medical checkups for the respective risk groups concentrate on the early X-ray detection of circular foci. As shown by recent studies, cytological sputum diagnosis, (tluorescence) bronchoscopy, and BAL cytology must be employed much more frequently in the high risk groups so that the prognostically more favorable stages of preneoplasm and carcinoma in situ can be detected and possibly treated curatively. These procedures are currently reaching a considerably higher sensitivity with the help of modern molecular biology techniques (e.g. detection of tumor- associated genetic changes and gene products). This contributes to an improvement in surveillance examinations with increasing detection of the curable early forms of tumors. However, only the further development of primary prevention, i.e. the greatest possible minim&&n or, if possible, total elimination of contact with carcinogemc agents and the consequent control of occupational protection will lead to a drastic reduction in the occupational risk of cancer.

Exposure to environmental tobneeo smoke and risk of lung cancer: The epidemiological evidence Tredaniel J, Boffetta F’. Saracci R, Hirsch A. Setice de Pneumologie, Hopifar Sainf-Louis. 1 Avenue Claude &lle&ux. 75475 Paris Cedex. Eur Respir J 1994;7:1877-8.

Exposure of nonsmokers to environmental tobacco smoke (ETS) is widespread in European eamtries, the most serious exposores occurring at home and in the workplace. Epidemiological studies available up to 1986 have been reviewed by several international and national authorities, which agreed in concluding that ETS exposure is causally related to lung cancer. A number of epidemiological studies have been published since then, and have confirmed this association. The possibility of positive results due to bias has been envisaged, it seems, however, that such bias could not explain the whole excess of lung cancer, Few data are available on confounders, such as diet and previous history of lung dixase, that might be responsible for the association; however, there is no evidence that they play an important role. Moreover, the biological plausibility of a causal association is supported by the similarity of the composition of ETS and active smoke. The causal association between ETS exposure end lung cancer now seems wcll- established; however, its public health impact is still debated. Estimates are available from the United Slates, Canada, Australia, New Zealand and England.

Passive smoking in the workplace: Classical and Bayesian meta- analyses Biggerstaff BJ, Tweedie RL., Mengersen KL. Deparfmenf o~Sfo!tifics, Colorado Sfafe University. Forf Collins. CO 80523. Int Arch Occup Environ Health 1994;66:269-77.

There we currently several dassical and Bayesian methods of meta-analysis available for combining epidemiological results. We describe and compare these in a consistent framework, and apply them to published studies of the relative risk of lung eaneer associated with exposure to environmental tobacco smoke in the workplace. We find that although all methods give reasonably similar combined estimates of relative risk of lung cancer associated with this exposure (none of which is significantly raised above unity, in either a frequcntist or a Baycsian sense), the approximations arising from classical methods appear to be nonconservative end should be used with caution. The Bayesian methods, which account more explicitly for possible inhomogeneity in studies, give sbghtly lower estimates again of relative risk and wider posterior credible intervals, indicating that inference from the non-Bayesian approaches might be optimistic.

Epidemiology and etiology

Lungadenoeareinomaandiodieatorsofssbestoserposure Mollo F, Pira E, Pi&to G, Bellis D, Burl0 P, Andreoni A et al. Depf Biomed. Sciences/Human Oncology Div. Pafhol. Anafomy/Hisfopafho[ Universiry of Turin. fia Stinfena 7. 10126 Turin. Int J Cancer 1995:60:289-93.

A case-control study was carried out on 145 male lung-cancer patients diagnosed at autopsy and 178 controls, in order to investigate the relationship between asbestos exposure and the cell type of pulmonary carcinoma. Adenoearcinomas (AD) were individually matched with other cell types and with controls. The relative risk (RR) of developing AD in relation with lung asbestos body (AB) content as tbc exposure indicator was calculated by using logistic-regression analysis for matched sets. Two cutoff levels, 1,000 and 10,000 asbestos bodies per gram dry weight (AB/gdw), were used in the analysis. In addition, AB counts were treated as a cxmtinuous variable (log AB + I). A significant association was found between AD and asbestos exposure, using levels and logarithmic transformation. However, an association of asbestos exposure with cell types other than AD could not be ruled out.

Badon and primary lungcaocer Mensrd 0, Schcid P, Anthoine D, Martinet Y. C/in. Pneumol. Medico- Chirurgicole. Hopifal de Brabois, CHU Nancy. Rue du Monwn. F S4Jll Vandoeuvre-les-Nancy Rev Mal Respir 1994,11:53145.

Radon is B natural radioactive gas. with worldwide distribution, deriving from uranium decay products, which can be inhaled, either in mining condition (extraction and management of uranium ores) or in domestic condition (in some high risk homes or geographic areas). The main epidemiologic studies on uranium mining workers have all confirmed an excess in relative risk of primary lung cancer. Epidemiologic studies on indoor exposure suggest a role of radon in the genesis of a certain number of primary lung cancer, although these results remain controversial and need to be confirmed. An overview of the main actual problems related to this bronchial carcinogen is presented in this paper.

Risk of lung cancer among cigarette smokers in relation to tumor location Shimizu H, Nag& C, Tsuchiya E, Nakagawa K, Weng S-Y. Deporhnenf o/ Public He&h, Cl& Universiry School o$Medicine, 40 T~kasa-machi, Gijii 500. Jpn J Cancer Res 1994;85:1196-9.

To evaluate the effect of cigarette smoking on lung cancer by tumor location and histological type, we eomparcd the smoking history obtained from medical records of605 patients with squamous cell carcinoma (194 males and 10 females) oradenocarcinoma(219 m&sand I82 females)ofthe lungand 183 patients with metastatic lung cancer (82 males and IO I females) who had been aged 40 years or over at the time of surgical resection at We Cancer Institute in Tokyo from 1973- 1991. The tumors which developed in a main or segmmtal bronchus were classified as central type, and those in a subsegmental or more distal bronchi were categorized as peripheral type. Cases with adenoearcinoma were classified by a pathologist into hvo histological subtypes, papillary and tubular types, according to the WHO lung carcinomaclassitication. Risk ofsquamous cell carcinoma was strongly associated with cigarette smoking for both central (OR (odds ratio) = 10.3 in males and 4.4 in females) and peripheral sites (OR = 10.7 in males and 6.5 in females). There was no significant association behveen cigarette smoking and adenocarcinoma for my tumor site or histological subtype in both sexes.

Silica dust exposure and lung cancer Koskela R-S, KIockars M, Laurent H, H&p&en M. Finnish Insf Occupafional Healfh. Topeliuksenkafu 41 a A, FlN-00250 Helsinki. Sand J Work Environ Health 1994;20:407-16.

Objecffve: The study evaluated the possibility of B direct association behveen silica dust exposure and lung cancer. Mefhods: Mortality and morbidity among 1026 granite workers was followed in 1940-1989. Regional census data for 1970-1985 and lung cancer incidence data were also linked. The cytotoxicity of different granite fractions and their capacity to Induce reactive oxygen species (ROS) in human leukocytes was studied in vitro. Renrlfs: Excess lung cancer