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A case-control study for evaluating long-cancer screening in Japan

Sobue T, Sttukl T, Naruke T. Departmenr ofFieldResearch, Research

Insfirure, Cemer for Aduh Diseases. Higashinari-ku, Osaka 537. Int J

Cancer 1992:50:230-7.

In order to evaluate the efficacy of lung-cancer screening, a case-

control study was conducted usmg the dala from 50 areas where

population-based lung-cancer screening programmes have been oper-

ated by local municipalities. In most areas, chest X-ray examinations

for all parucipants and sputum cytology for lngh-risk parttctpants were

offered annually. Case series consisted of 273 deceased lung-cancer

cases. For each case, 2 to 5 controls (a total of 1,269 controls) were

collected from those who were ahvc at the time of dlagnosls of the

correspondmg case, matched by sex, age, smoking status and lype of

health insurance. Cases and controls were hmited to a high-risk group

for males and a non-high-risk group for females. Screemng historles,

winch wereobtainedfrom the listofscreenees, werecompared between

case and matched controls for the ldenrtcal calendar period before the

time of diagnosis of the case. The odds ratio of dymg from lung cancer

for those screened within 12 months vs. those not scrccncd was 0.72

(95% confldencc interval 0.50-1.03: p = 0.07). The odds rauos I”-

creased towards unity, as the length of ume in which screening histories

were compared increased. After adjustrng for some other variables,

which appeared to be associated with the opportunities of chest X-ray

examination, the csumated odds ratio did not change. These results

suggest some bcncfits from lung-cancer screenmg m terms of reductmn

of lung-cancer mortality and should bc subject to further rcscarch.

Epidemiology and etiology A case-control study of lung cancer in a cohort of workers potcn-

tially exposed to slag wool tibres

Wong 0, Folian D, Trent LS. Applied Health Sciences, 181 Second

Avenue, San Maleo. CA 94401. Br J Ind Med 1991;48:818-24.

A cohortof men were IdentIfiedas having worked for more than

a year at nme slag wool plants. Some of these men were potentially

exposed LO man made vxreous fibres (MMVF). The vital status of the

entire cohort was ascertained to the end of 1989. Of the 504 deaths that

occurred between 1970 and 1989, 61 were attributed to lung cancer

(cases). Individually matchedcontrols were randomly selected from the

remammg deaths. Attempts were made to locate and interview the

surwving famlhes of the cases and controls. The families of three lung

cancer cases could not be located and no matched controls were found

for another three cases. Included in the final analysis were 55 cases and

98 controls. Estimates of mdwdual exposure to MMVF were based on

employment records and industrial hygiene surveys. Data on smoking

and hlstorlesofemploymentoutsrdetheMMVFindustrywereobtained

from telephone interwews and employment records. Relatwe risks

were calculated for cigarette smoking and exposure to MMVF. No

mcreased risk of lung cancer was found associated with exposure to

MMVF, and analysis by cumulative fibrccxposuredid not inthcate any

trend. As expcctcd. cigarette smoking was found to be responsible for

the observed mcrcasc in mortahly from lung cancer in this group of

MMVF workers, and the risk increased wth increasing pack-years of

clgarcttc smoking.

Lung asbestos fiber content and mesothelioma cell type, site, and survival

Lclgh J, Rogers AJ, Fcrguson DA, Mulder HB, Ackad M, Thompson R.

Nalwnal lnsr~fu@ of Occupalumal llealfh and Safely. GPO Box 58.

Sydney. NSW2001. Cancer 1991;68:135-41.

All asccrtamable cases of malignant mcsothchoma in Australia wcrc

nollfied to a national survctllance program in the period January I, 1980 lo December 3 I, 1985. There were 854 cases obtained and 823 con-

fIrmed on clinical (77) or hwologic (746) grounds. Tumor site was

known in 759 cases (685 pleural and 74 peritoneal). Lung fiber content

analyses by hght microscopy and analytic transmlwon clcctron rn-

croscopy with energy- dispersive x-ray analysis were done on 226 cases

in which postmortem material was avadable, using the method of

Rogers. Cell type was determmed by a five-member expert panel of

pathologists appointed by the Royal College of Pathologrsts of Aus-

tralasia. There was a slatistically significant trend between lung fiber

content (fibers/g dry lung) and cell type from epithclial (low fiber

content) through mixed to sarcomatous (high fibercontcnt). Tlus trend

was most apparent for total uncoated fibers (chl-square = 6.8, df = I. P

less thanO.Ol)andcrocidolite(chi-square=6,7,df= I ,PlessthanO.Ol).

Lung fibercontentalsowasassociated with tumorsite; higher lung fiber

content being associated with peritoneal tumors. Tlus relationship was

significant for all fiber content measures except chrysotlle and was

independentofthe fibercontent-cell typcrclationship(log-linearanaly-

SIS). Survival from time of provisional diagnosis was significantly

longer for cplthehal (mean, 13 months; standard deviation [SD], 12.X)

and mixed (mean, 10.2 months; SD, 8.7) types than sarcomatow cell

types (mean, 5.8 months: SD, 6.5; P less than 0.0001, by analysis of

variance on log,, survival time). Survival tune was sigruficantly grcatcr

for pleural tumors (mean, II .4 months; SD, 13.4) than pwtoncal

tumors (mean, 8.6 months; SD, 12.5) (P less than 0.005, by Student’\ t

test on log,, survival time).

Lang cancer in filling station attendants

Grandjean P, Andersen 0. lnsrirule of Communuy Heailh, Odrnse

University, J.B WinslowsveJ 17. 5000 Odense C. Am J Ind Med

1991:20:763-8.

A1 the Damsh census on 9 November 1970,4,055 men and 1,195

women aged 20-64 years Indicated an employment tbat was coded =

retail sale ofoil and gasoline: almost all indwiduals probably worked as

filling slation attendants. Record linkage at Danmarks Stattstik showed

that 529 of :he men had died during the following 17 years. Respiratory

cancer (75 deaths) was the only cause ofdcath that showed a sigmfxant

~XCCSS (standardized mortahty ratto, I .58; 95% confidcncc rntcrval,

I .25-2.00) when compared to all men gamfully employed at the tlmc of

the census. An mcreased mortality due to carthovascular disca could

not be related to any parucular diagnosw subgroup; the mortahty in

women did not differ from cxpxted rates. These results arc in accor-

dance wth data from other countries on occupauonal groups exposed to

lngh levels of exhaust fumes.

Long cancer and smoking trends in the United States over the past

25 years

Garfinkel L.SilverbergE.AmerrcanCanterSuc~ely.New York,NY.CA

Cancer J Chn 1991;41/3 (137.145)

Lung cancer rcmams the leading cause of cancer incidence and death

in the United States. Uslng data from the National Center for Health

Statistics and the American Cancer Soclcty’s two large-scale prospec-

tlve Cancer Prevention Studies, tbc authors analyz the 25.year trends

in lung cancer incidence and mortality, smoking patterns, and the

growmg problem of clgarcttc exports to other countries.

The occupational cancer incidence surveillance study (OCISS):

Risk of long cancer by usual occupation and industry in the Detroit

metropolitan area

Bums PB, Swanson GM. College of fluman Medlcme, A21 I Easr Fee

Hall, Michigan Stale Unruersiry, East Lansmg, MI 4X824-1316. Am J

Ind Med 1991;19:655-71.

This case-referent study assesses occupational risk factors associated

with lung cancer, utilizingcolonandrectum cancer referents. Complete

occupational and tobacco use histories were obtained by telephone

interview for 5,935 inctdent lung cancer cases and 3,956 incrdent colon

and rectum cancer referents. The analysis mcludcd 43 usual occupa-

tional groups and 48 usual industry groups comprised of at least IO

cases. Among all cases, there were signil’lcant clcvated risks for

excavating and minmg workers (OR = 4.01). furnace workers (OR =

232

3.1 I), armed servic& personnel (OR = 3.10). agricultural workers (OR = 2.05). driver sales (OR = 2.21). mechanics (OR = 1.72), painters (OR = 1.96). and drivers (OR = 1.88). Industries with significant elevated iungcanccrriskincludedfanning(OR=2.2l),mining (OR=2,98),and primary ferrous metals manufacturing (OR = 2.43). Analyses of white and black men separately revealed that the excess of lung cancer among mechanics is restricted to black males (OR = 4.16). The risk of lung canceramongarmedservices personnel is higheramong blackmen (OR = 10.54) than among white men (OR = 3.06). Five of the occupations observed more often among lung cancer cases have probable exposure to diesel exhaust.

Carcinogenic risk of non-uniform alpha particle irradiation in the lungs: Radon progeny effects at bronchial bifurcations Hofmann W, Crawford-Brown DJ, Menache MG, Martonen TB. Ableilung fur Biophysik, Universitor S&burg. Hellbrunnersrrasse 34, A-5020 Salzburg. Radial Pro1 Dosim 1991;38:91-8.

The combined effect of enhanced deposition and reduced clearance at bronchial bifurcations leads to increased radon progeny doses within branching sites compared with uniformly distributed activity within a given airway generation. A multi-stage carcinogenesis model was used topredicttheprobabilityoflungcancerinductionatdiffcrentsitesofthe bronchial region. For relatively low radon progeny exposures, lung cancer risk is significantly higher in bifurcation zones, particularly at carinal ridges, than along tubular segments. At sufficiently high expo- sures, however, lung cancer risk is highest in the tubular portions of a generation. This suggests that the common assumption of a uniform dose distribution provides realistic risk estimates for high uranium miner exposures, but may underestimate lung cancer risk at low, environmentalexposures. Ifconcomitantexposuretocigarettesmokcis factored intoourriskanalysis mamultiplicative fashion.then theeffect related to risk inhomogeneity becomes even more pronounced.

Relation of bronchioloalveolar carcinoma to tobacco Morabia A, Wynder EL. American Healrh Foundation. 320 E43rd Street, New York, NY 10017. Br Med J 1992;304:541-3.

Objective - To determine whether bronchioloalveolar carcinoma is related to tobacco use. Design - Case-control study. Setting - 11 teaching hospitals of Chicago, Long Island, New York, and Philadel- phia, 1977-89. Subjects - 87 patients with histologically diagnosed bmnchioloalveolar carcinoma (cases) and 286 non-cancer and 297 cancer patients matched to cases on age, sex, race, hospital, and date of admission. Results - 10% of male cases and 25% of female cases had never smoked. Relative risks of bronchioloalveolar carcinoma (as estimated by the relative odds) were greater for subjects who started smoking at a younger age, smoked for a longer time, or smoked more cigarettes per day. Relative risks decreased proportionally to the dura- tion of smoking cessation. Conclusion - Smoking plays an important part in theaetiology of bronchioloalveolar carcinoma but is not the only potential cause because of the large proportion of never smokers among patients with this disease.

Theriskoflungcancerandmesotheliomaafterccssation ofasbestos exposure: A propsective cohort study of shipyard workers Sanden A, Jarvholm B, Larsson S, Thiringer G. Department ofoccupa- tional Medicine, St. Sigfridsgatan 85. S-412 66 Goteborg. Eur Respir J 1992;5:281-5.

A prospective cohort study of 3.3893 shipyard workers, mainly exposed to chrysotile, indicated no increased risk of lung cancer 7-15 yrs after exposure to asbestos had ceased. The shipyard workers, however, liad an increased risk of pleural mesotbeliomas with 11 observed cases versus I .5 expected. An explanation for these observa- tionsmay bethatasbestosmay havediffcrentcarcinogenicmechanisms in causing lung cancer and mesothelioma. A non-increased risk of lung cancer some years after exposure to asbestos has stopped is in accor- dance with asbestos acting as a promotor. The high risk of mesotheli- oma, on the other hand, may indicate that asbestos acts as a complete carcinogen in developing this disease.

Dietary cholesterol, fatty acids, and the risk of lung cancer among men Knekt P, Seppanen R, Jarvinen R, Virtamo J. Hyvonen L, Pukkala E et al. Research lnstirute for Social Security, Social Insurance Institution, Helsinki. Nutr Cancer 1991;16:267-75.

The relation between dietary cholesterol and fatty acids and the incidence of lung cancer was studied among 4,538 Finnish men aged 20-69 years and initially free of cancer. During 20 years of follow-up, 117 lung cancer cases were diagnosed. Cholesterol intake was not associated with lung cancer risk, the age-, smoking-, and energy- adjusted relative risk between the lowest and highest tertiles being 1.0 [95% confidence interval (CI) = 0.6-1.91. The intake of saturated fatty acids was nonsignificantly related with lung cancer incrdence, the relative risk for the lowest compared with the highest tertile being I .6 (Cl = 0.8-3.2). The association was stronger among smokers than among nonsmokers, the relative risks being 2.1 (CI = 1 .O-4.3) and 1.3 (CI = 0.4-4.1). respectively. Therelativerisk among smokers, however, decreased to 1.5 after adjustment for the amount they smoked. In the total cohort, there was a significantly elevated risk of lung cancer among men with a high intake of butter, one of the main sources of saturated fatty acids, the relative risk being 1.9 (CI = 1 .l-3.2). The present data do not confirm previous results suggesting that dietary cholesterol predicts the Occurrence of lung cancer among men. The association between intake bf saturated fatty acids and lung cancer observed in the present study may be partly due to heavy smoking among high consumers of saturated fat.

Epidemiology of passive smoking Uberla K. Institut fur Medirinische Informationsverarbeitung, Biom- etrie tutd Epidemiologic. Ludwig-Maximilians-Universitat, Marcion- inistr. IS. 8oW Munchen 70. Z Hautkr 1991;66(Suppl2):26-9.

Statistical facts on lung cancer arc presented. The study from HIRAYAMA is discussed and its weaknesses are analysed. The results of a re-analyses of his data are presented. There are two cohort studies with divergent results and 21 case control studies. All case control studies have serious weaknesses. A met&analysis shows, that studies with low methodological quality have a higher relative risk (1.79) in comparison to studies with better methodological quality (1.09). Only 3 out of 10 criteria which are generally used to establish a causal connection from epidemiologic studiesarcpartially fulfilled. All epide- miological data can be explained by bias, confounding, misclassifica- tion or chance as well as by accepting the alternative hypotheses. A causal connection between environmental tobacco smoke and lung cancer is a serious hypothesis. Using the. critical view of a scientist one can equally well adhere to the nullhypothesis with good reasons.

Comparison of hvocarhoplatin-containing regimens with standard chemotherapy for small cell lung cancer in a randomised phase II study Postmus PE, Splinter TAW, Palmen FMLHG, Camey DN, Festen J, Burghouts JThW et al. Department of Pulmonary Diseases, University Hospital, Oostersingel59,9?13 EZ Groningen. Eur J Cancer 1992:28:% loo.

The EORTC Lung Cancer Cooperative group performed a random- ised phase II study in patients with small cell lung cancer comparing the standard cyclophosphatnide/doxorubicin/etoposide (CDE) regimen with two regimens containing the new and active cisplatin derivative, carboplatin,4OOmgfm*incombination with ifosfamide,adrug without important myelotoxicity, at a dose of 5 g/m’ (IMP) or the non- myelotoxic drug vincristine twice 2 mg (VP). Of 178 evaluable patients, 63 received CDE 130 limited disease (LD), 33 extensive disease (ED)], 55 received IMP (22 LD, 33 ED) and 60 (26 LD, 34 ED) were treated with VP. The response duration was not statistically different: CDE 31 weeks, IMP 29 weeks and VP 21 weeks. The time to progression after CDE was 28 weeks, IMP 24 weeks and VP 17 weeks. This was significantly shorter afver VP than after CDE (P = O.O17).The 60%