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FILE NAME Quebec Asbestos Mining Association QAMA DATE 1952 DOC QAMA006 DOCUMENT DESCRIPTION Journal Article - Survey of Some Current British and European Studies of Occupational Tumor Problems Sys Sead es Be Bt: en cmt oe re id ; ss be ce carey [ey ORE TELA ATTA eg rarPa ot 6 y eee a Eee dk . . . - e 1952 11952952 Durin work has + he made dermatiti i which 1 : , been exp SURVEY OF SOME CURRENT BRITISH AND EUROPEAN OF OCCUPATIONAL TUMOR PROBLEMS STUDIES WILLIAM E. SMITH M.D. 4 4. q 1 Case varying si The erythe CASE 2 NEW YORK # in Case . - N JUNE 1950 sailed New with visiting N JUNE 28 1950 I sailed from New York with the object of visiting ini- scars the arms and viduals engagedin the study of occupational tumor problems abroad ence gained from these visits provides the material of this report and presented under the following headings Experi- will be 1. Shale Oil . : II Petroleum III Asbestos . 30 years -. 3 Case 3 . B wer Theyyears * years 4 of : kera four kera skinskin IV Dyestuffs but Dr. but Dr. S V. Sources of Statistical Data on Occupational Factors in Cancer 1. SHALE OIL . : a from an c . fading de P The latte Skin cancers in paraffin workers in the Scottish shale industry were noted a as long ago as 1876. In 1923 a detailed study of this problem with a report of 65 "e 3 cases was prepared by Dr. Alexander Scott at the request of the Scottish shale . for medical industry continued since time industry Dr. Scott has continued since that time to serve as medical consultant for { obstructic wer They the parafdevel this case the industry and as works physician ( had the privilege of visiting him at the . Pumpherston Works in Calder Scotland where I also had the pleasure of S meeting Mr. Alan Anderson the works manager Dr. E. Smith the chief chemist pt { and Mr. Crombie works chemist Mr. Crombie gave me a tour of the plant He stated that oil shale the material taken out of the earth is retorted at 1000 to ] 1900 F. at four plants in Scotland to yield naphtha ammonia and crude oil The # yield Works proces ed products are then sent to the Pumpherston Works where they are processed to yield gasoline yield gasoline industrial industrial industrial naphthas paraffin paraffin diesel diesel oil oil coke and acid acid The sludge The , paraffin is obtained by a pressing operation to be commented on in more detail by to be em All abnorm In thisthis in oiloil worl worlworl or arms tumtumoors rs The later . in the " Presented at a meeting of the Cancer Prevention Committee in New York Oct. 18 1950 Dr. Smith is Assistant Professor Department of fundustrial Medicine Grad 1/19 remove is allow Medical School New York University Travel expenses involved in the preparation of this survey were met by grants front de Anna Fuller Fund and from New York University 1. Scott .: On the Occupation Cancer of the Parallin and Oil Workers of the s Shale Oil Industry British M. J. 2 1108-1109 Dec. 9 1922 The Occupation Dermat + the Paraffin Workers of the Scottish Shale Oil Industry with a Description on the Syste Adopted and the Results Ohtained at the Periodic Examinations of These Wurkmen bis Scientific Report Imperial Cancer Research Fund London 1923 pp 1-94 Shale Oil Indtastegi Occupation and Health Report No. 242 International Labour Office Geneva 1925 2. A Brief Description of the Operations of the Scottish Shale Oil huldustry Scottish Oils- Ltd. Glasgow 1948. 32 pp 242 t scaly o paraffi laborer lalaborber orer existing On experie been b case ol large large , that d ARCHIVES HYGIENE & OCCUPATIONAL eeROT AMA ohyt IEE ates tel eee AS name * Vee ee tee - INDUSTR a . oo MED . e+ wehbaes . ow ' vi rs Re"! a. z " rs . : f oo ' : - a: 1 ~ .. 4 jg . lou: yo. too ; S n j 10 25 : 3r . m : of ZA 7 ZA By - a? hd BRITISH AND EUROPEAN TUMOR PROBLEMS 249 He then covered his arm again with the lubricating oil but this time rubbel it off with cotton soaked in a colorless technical grade of white oil Almost all the fluoress cence was thus removed only a little remaining in very few scattered hair follicles Dr. Cruickshank stated that he had not found dermatitis to result in human skin washed repeatedly with white oil provided the skin was healthy to start with Cases of irritation occurred when the oil was applied under dressings Further discussion ni ways to protect the skin against oils is contained in my section on Shale Oil Dr. Cruickshank and Proi Squire have described warts that occurred on the _ skin of 33 of a group of 138 machine operators exposed to sprays of cutting oil which they found capable of inducing skin tumors in animals had an opportunity to examine many excellent photographs of these men Some of the lesions were flat white keratoses others were raised rugose and p^zmente Histological sections showed the latter to be papillomas One man har a scrotal carrer sertions of which I saw Photographs of his arms showed half a dozen small papilloma Prof. J. W. Cook at the University of Glasgow is attempting to rewily the chemical nature of the carcinogens in the petrikoan oils ever ever biology test at Birmingham Prof. Cook was away from Glasgow when visited his laboratory but the work was described to me by his assistant Dr. W. Kurmakers Kurmakers K vacuum distillation chromatography acid they have isolated a chrysene general procedure is to extract the mis on ahmina with a bar dia with adfur adfur and pundation pundation aligheid ale alumina columns and elute with petroleum benzin They Lace thoes bed On crystalline compounds as yet unidentified of which to an art art has been obtained in sufficient quantity for bad teg tet nre rt ten per hand They have failed to find benzpyrene The method of aromatics with sulfuric acid regenerate the hydrocarlins hydrocarlins seed was to entrant the and ne dhe direnean direnean cence spectroscopy Dr. I. Hieger of the Chester Beaux also said to have searched unsuccessfully & genic at Birmingham I may may note here that a of tion of benzpyrene was demonstrated Kennaway's Kenaway's laboratory laboratory in Kennaway's laboratory London account An benapj ncn cre very Dr. shing shing Po Po Lt : ow in the British Journal of Cancer vas useless as a means of idenuiying odmapeamits odmapeamitodmsapeamits on mu emphasized the need for uorescence spectr EY, M^ S ; FYI FYI FYI or : ne a ty oq ma 1 cane cane of the lungs in the the 23 years from 1924 years whether sttom whether lung pieura in 15.2 0: acl so which phases aard aard The data cited above Cruickshank N. and aquru the Use Mineral Oil ] Brit Indust of Annual Report the Chief Majesty'sMajesty's Stationery Office UR p 71. : pte wots te ta. ct tet th the : Lae e Ere? ete . , * we, ma HE tee HE wn aS 29S =F Il ety ASS ae Rech Rpt a8 ast a we " : wasG " 3 ie PTR een nye ah eal at O=e ges o .2< - ba: - Cy oth a OD ; hai Rigs : P : eh picSes: ae ee et * 4 rkwi > o i ie by i a tp . c a . 7%. be $y . }s 3 a = Yee? aa * | hae ry s . etie. BY j 4 vw. 4 a 4. Ped i a 4 Pe OS AEB ats Gm seree nah 250 INDUSTRIAL HYGIENE AND OCCUPATIONAL MEDICINE Dr. Merewether referred to the governmental report published in 1930 by him self and C. W. Price This report showed that asbestosis developed in 80 " men employed 20 or more years in the industry * and that in various groups r workers the percentage in which asbestosis developed varied directly with the dus ness of the process in which the groups were engaged These findings le : the adoption of laws requiring ventilation of asbestos work rooms in Great Brita Asbestos Industry Regulations 1931 Detailed specifications for safety equi ment are contained in Factory Orders 194. It should be noted that there is i mining of asbestos in England Hence the British figures refer only to individu engaged in weaving or other manufacturing or handling operations A first problem was whether the apparent association of lung cancer and asbes tosis means merely that workmen's compensation procedures funneled all ches diseases into one group This possibility cannot be supported however for n such high incidence of lung cancer has been found in cases of silicosis which are likewise reported to and reviewed by the Pneumoconiosis Board Cancer of the lungs or the pleura was noted in only 91 1.32) of 6,884 cases of silicosis recorded from 1930 through 1946. The incidence of cancer was thus 10 times greater ^fin ashes- totic lungs than in silicotic lungs Data on the average age at death in this silicotie group were not given but the same report listed a series of 1,037 silienties who died at an average age of 58.2 years compared with a group of 160 asbestoties who died at an average age of 47.5 years Therefore the difference in cancer incidence in the two diseases could not be attributed to death of silicoties before they reached the cancer age in fact the silicotics would appear to have had greater opportunity by a full decade to yield cancers Similarly the average duration of employ- ment in these two groups could not account for the difference 34.3 years for the silicotics against 14.9 years for the asbestotics A measure of the rate at which lung cancer occurs in the general population oi England and Wales can be found in the Registrar General's Statistical Review 1949 Employing the data given on pages 3 and 145 of the Review one can calculate that 1.36 of all deaths in the three years from 1943 to 1945 were reported as due to cancer of the lung the bronchus or the pleura It is of interest to note that the percentage of deaths attributed to lung cancer in the general population is almost identical with the figure of 1.32 for the finding of lung cancer in a large group of silicotic lungs Documentation of the cases of coexistent lung cancer and asbestosis became my next endeavor For this purpose I visited Dr. S. Roodhouse Gl^,yneat the Institute for Social Medicine in Oxford Dr. Gloyne's studies of the pathology vi asbestosis are well known For many years he has received lungs for review ou matters of compensation Dr. Gloyne generously gave me permission to cite the data in Table 1 which he assembled from lungs that he personally examined in the gross and microscopically It is to be hoped that a full accoum of them will . 17. u Merewether E. A. and Price C. W Report on Effects of Asbestos Dust on Lungs and Dust Suppression in the Asbestos Industry London His Majesty's Stationery Offic 1930 summarized in J. Indust Hyg & Toxicol 117 1930 and in Tubercle 09-81 16 118 and 152-159 1933-1934 b ibid p 10. Table 3 e ibid p 14. Table 7 18. Gloyne .: The Morbid Anatomy and Histology of Asbestosis Tubercle 445 493-497 and 550-558 1932-1933 Asbestosis in Silicosis and Asbestosis velited by Lanza New York Oxford University Press 1938 pp 225-244 437 A. published - death.,," In ad 169 perso those incl 8.3 ) gross or asbestotic 10 men to be n incidence sex ratio wil without ~fi coninses for the g found fr Table 1. Iron Pott Cou Ston Asbe described this elev continue in his se scattered The tosis gr | tuberend Table cancerer bruchi bruchi fot.pd +4 oN thi i] ' [oa A. Saad i ... ca. .with 1-721 Ee tp sata eCREEYT aad es rie AN . A, i . ae s : , .im-1 Es of . sti- . to to cain lip- lip- lip- tals tals ote test test are ngs . ngs ma a es- tic ho ..ho ..ho Ice tet ed a or- by- the , of of WW an - ed te on a : 2476 2476 2476 c ; on he 223 ; 223 22 4 22 @ 22 . 1 * : an ae .-f mo 4% F BRITISH AND EUROPEAN TUMOR PROBLEMS 251 published from a manuscript that was in preparation at the time of his recent death.,, In addition to the material of Table 1 Dr. Gloyne also examined the lungs of 169 persons without pneumoconiosis but employed in the same set of industries as those included in Table 1. Among these he found 14 who had primary lung cancer either in 8.3 8.3 The lungs of 11 asbestos workers who had no asbestosis either in the microscopicaly microscopical y negative for carcinoma The in gross or microscopically were negative for carcinoma The 17 cases of cancer in asbestotic lungs Table ) were about equally distributed between men and women 10 men 7 women whereas in the normal population in England the ratio is said to be 4 men to every woman with cancer of the lungs In addition to the higher incidence of cancer in asbestotic lungs Dr. Gloyne felt that this difference in the sex ratio afforded evidence for an occupational factor It will be that the cancer rate of 8.3 foundin the 169 individuals apparent lung without pneumoconiosis and the rates of 5.1 to 8.9 in the groups with pneumo- conioses asbestosis higher of 1.36 estimated conioses other than asbestosis are much higher than the rate of 1.36 estimated for the general popopulaption ulation on the basis of death certificates and the rate of 1.327 found from pathological examination of the large group of silicoties previously of Pneumoconiosis of Primary Lung Types Incidence Primary TABLE Incidence Cancer Cancer in in Groups with with Various Various of Pneumoconiosis = Data of S. Roodhouse ) Gl^,yne Ce nme nee corr . Occupationul Group Persons ee with Prestito eniessis oe Number Percentage Total with Pimary with Primary Ninaber Lung Cancer Lustig Vabrer Iron and steel workers ws ' Pottery workers .......,. 340 10 Coal miners ....-.0+.0+- HXI Is Stonemasons .occeseererooeee : ... - Asbestos workers Lec ecccccceceeeeetseesetneneetes 181 17 3.1 30 4.3 -3 14.0 ee ee eee ee ee ee higher described is described It is thus probable that the higher rates reflect closer study Despite Despite this elevation of the base line for comparison the rate in the asbestosis group continued to stand out Dr. Gloyne stated that of the total number of lung cancers in his series 7.5 were discovered only various scattered through the various groups The type of " " cancer and the degree on microscopic asbestosis of asbestosis in examination 17 the 17 cases These were of the ashes- tosis group are given in Table 2. Only one individual M. S. had evidence of tuberculosis In the 922 cases comprising the whole of the pneumoconiosis group Table Table ) 20 showed tuberculosis Dr. Gloyne made a special search for pre- cancerous changes in asbestotic lungs and did not detect any Desquamation of bronchial epithelium was occasionally seen but squamous cell metaplasia was not four save in the cancers themselves It will be noted from Table 2 that the degree 17. A brief posthumous publication has appeared Gloyne S. .: Pneumoconiosis Likewal Likewal Survey of Necropsy Material in 1,205 Cases Lancet 810-813 1951 A His- 29 Through the courtesy of Dr. K. F. W. Hinson of the London Chest Hospital we have revived lobes from six lungs of Dr. Gloyne's series This material was examined by Dr. Douglas \ underland of Memorial Hospital New York Two cases C. W. and J. W. classified as Sjuamous cell cancer by Dr. Gloyne were interinterppted reted as terminal bronchiolar alveolar cell carcinoma carcinoma by Dr. Sunderland ee neea Baieas =eea ie,) aot esr ae ey : oe; . . 3 : oe $c pay et wine eter AoRnd O Poy 5 i. ear at as i Ls Bek aes srg ay om f tke eed 3 a2 2 = ie { ERAS ed SFr Ss AD ee . se & Ma 7 bBeees ties { ASS Ye 5 Ree on ; ae Be Bis i & eprrs BSetsns3. om = a RR Ss 4 cps alkane > Be : am BoS St KR ca i Recep i Pig 2 wp eats, ey Pits 4 zs + Fo iS y ie pepe, 1 SRW : Behe sete Rast : 7 + eet t fas ik ' oe bead q SoM . i Rea He i Be eA! a4 i Coat it T&a"y ae ters By Bre4e.s 4 een Sc b ee . ; By ee oe 4 a t. 7 oy otet. Dennmae i . he fone Se & iY Pd: te ee tee E tN e 9 wea Peg + me ows LA eee: % vi e Poe Owen ane sme paghis s na= owe rat eg a anehee. ar yeS.E2ye ee g. . IP} : t Nee rir sie Ps? : Ny Ss, rd . 7 eel we: Ph po : nate : rene YQ. Oe. owe a a sta Se 252 INDUSTRIAL HYGIENE AND OCCUPATIONAL MEDICINE of asbestosis in the of extensive in group cancerous lungs was recorded as moderate or every case except one where it was mild degree of asbestosis The estimation of the The 17 was made in every instance by the same observer Dr. Gloyne were cases of coexistent lung cancer and asbestosis studied by Dr. assembled over a period of 20 years 1929 to Gloyne to asbestos prior to 1932 the year modern 1949 All had their exposure in conformance with exhaust ventilation devices were adopted government regulations plant handling Rhodesian The majority were employed at a blue and South African also blue asbestos Both types are more brittle than Canadian white asbestos hence these At least one patient J. I. however was stated give rise to more dust Canadian white asbestos to have been exposed only to I next visited Prof. E. J. King at the British London where I had the Graduate Medical School in opportunity to examine protocols relating to the lungs TABLE Pathological Findings in 10 Men and 7 Women with Asbestosis and . Data of S. Roodhouse Gloyne Lung Cancer Patient Mules Degree Asbestosis Type of Cancer Extensive Extensive Moderate Moderate Moderate Molerate Moderate Mudderate Modernte Und Extensive Extensive Meulerute Morierute Moderate Moderute Muslerate Oat C'ell Oat Cell Squamous Cell Squamous Cell Squamous Cell Squamous Cell Squamous Cell Squamous Cell Squamous Cell Oat Cell Squamous Cell Squamous Cell Squamous Cell Squamous Cell Out Cell Oat C'ell Adenocarcinoma of 11 individuals who had been The employed in plant using Canadian white asbestos pathological descriptions were made by Dr. C. V. Harrison of asbestosis were noted in 8 of Harrison Varying degrees the 8 asbestotic lungs these 11 lungs there were 3 cancers all lungs An oat cell cancer was found in among male with extensive asbestosis lungs of one patient patients males in Anaplastic carcinomas were described in two one of whom the degree of asbestosis other the asbestosis was minimal was moderate The asbestosis ranged from extensive erate in the 5 remaining patients in whom this disease extensive to mod- cancer Combining the data of Dr. was not complicated by 20 cases of coexistent Gloyne and Dr. Harrison one finds that in extensive in lung cancer and asbestosis the degree of asbestosis 5 moderate in 13 and mild or minimal was was squamous cell in 11 oat cell in in 2. The cancer There was no 6 anaplastic in 2 and adenocarcinoma in I correlation between between type of cancer and degree of asbestosis next visited Dr. Hubert Wyers the medical engaged in manufacturing asbestos officer for a company in England Rhodesia products from blue asbestos mined in or f the ne ~. oyne sure opted at dust ve -- cer sg, AND EUROPEAN TUMOR PROBLEMS 253 BRITISH or South Africa Dr Wyers is the author of a valuabalendclitnhiactaltshteudiyndoufstarsybegsrteowsitso He stated that asbestosis was recognized in 1900 deaths from of 1914-1918 Dr. Wyers has seen only two major stature in the wwhaor started to work in the industry after 1932 the year when deaths asbestosis in people ventilation devices were installed In contrast he had seen 115 exhaust before 1932. He feels that the regulations involving asbestosis in persons employed therefore a great triumph _ in regard to safety conditions in the asbestionstihnedussetvreryitayreof the disease in terms of of preventive medicine The dimiinsutfiurotnher borne out by lessened severity in the the number of persons affected with deaths sometimes occur- individual cases Prior to 1932 the disease was acute The disease as it is now seen is much more ring after two years of exposure asbestosis seen by Dr. Wyers primary lung cancer was chronic In the 117 cases of 17 cases and his pathological found in 17. Dr. Gloyne examined the lungs in these of the tumors have been given above diagnoses with asbestosis and lung cancer were exposed before All of the 17 individuals 3 cancer patients studied by 1932. According to lDirk.ewiMseereewxepotsheedr btehfeoraeddi1t9i3o2n.al I specifically inquired of Dr. Harrison were had been Dr. of coexistent lung cancer and asbestosis Merewether whether any cases had taken place only since 1932. He stated reported in individuals whose exposure that of a man employed in the industry that only one such case has been reported of the 1935 and 1945. This single case might well be expected as part bneotrwemeanl incidence of lung cancer in any group as large as that employed in the asbestos industrythen I was able to find some information on a total of 21 persons working In summary and asbestosis of whom only one was a man with coexistent lung cancer The additional 10 patients making under conditions now prevailing in the industry of Fac- the total of 31 described in the Annual Report of the Chief Inspector utopries for the year 1947 had all been exposed prior to 1932 and I did not attempt prevailing to locate autopsy protocols describing them and Dr. Merewether that the It was the consensus of Dr. Gloyne Dr. Wyers that it is less in England has changed so nature of the disease asbestosis as seen in the industry has taken common less severe in individuals whose employment tumor hazard forinerly place only since 1932. It was the consensus that a lung but that there is no evidence to show that existed in this industry in Great Britain such a hazard continues to exist under the working conditionDsr.nMoewrewether slows slows It should be further noted that in the 1947 factoorfy 1r.e5potrot40 years existed in the ibat a mean exposure of 16.5 years with a range Individuals beginning cases of asbestos workers who succumbed to lung cancer in the 1930's are therefore only now reaching the mean age at diwir employment The size of this group is not known -h^ch tumors might be expected to appear cancer but the fact that it has thus far provided only a single case un vexistent lung hazard has been greatly diminished at and asbestosis argues that any hung tumor number of cases with least in point of time Whether there will be any significant ; experimental delayed appearance remains Prof. King described his conioses In the case of experimental to be seen studies on the use of aluusiua ^fin pretnos experimental beneficial effect asbestosis alumina had no 21. Wyers .: Asbestosis Postprat Postprat M. ( 26 431 637 1958 ey aay ASE P RENIN tA ALA ASY hoe og he YS oF a AS eet TNO CET RS Oa EE WG RaE e SD Rae: a Mor, as Siw La ASSOLE i pe (i at ages en a. a ae i . { i | i i i : t i ! | i i | ; f : ne etm ee ; : ' ; Ste ee : a ers e ! ! ; } . ' ; : i 3 , 254 INDUSTRIAL HYGIENE AND OCCUPATIONAL MEDICINE in either of two series of tests examined histological sections of rat lungs that had received intratracheal instillations of asbestos fibers Studies of these lungs have been published Prof. King stated that he had found no difference in the response of rat lungs to Canadian as contrasted with Rhodesian fibers nor had any epithelial changes been evident A few pulmonary adenomas were present in the slides shown me but these tumors are known to occur spontaneously in rats and cannot be attributed to the instillation of asbestos fibers In regard to the animals chosen for experimental work Dr. Gloyne stated that he had found rabbits and guinea pigs more susceptible to asbestosis than rats He had not tested mice See Abstract of Discussion at end of this paper for further comments on lung cancer in relation to asbestosis . ~ IV DYESTUFFS In the light of the evidence that bladder tumors are caused by naphthyl- amine in the manufacturing industry production of this chemical was reportedly discontinued as of April 1950 by Imperial Chemical Industries and by the Clayton Aniline Company the largest British dye producers They are said now to make sulfonic acids by sulfonating naphthol and aminating it later thus avoiding the stage at which naphthylamine is produced This change in the manufac- turing process should not only protect workers in the plants but also remove the potential hazard of distribution of free naphthylamine as a contaminant of food dyes consumed by the public The question whether benzidine presents an occupational tumor hazard has long been debated A recent paper by Barsotti and Vigliani presents an impressive series works of cases of bladder tumors attributed to benzidine exposure in an Italian It is claimed that majority of the patients had not been exposed to naphthylamine A translation of this Italian study appears in an accompanying paper Dr. Kenneth Baker of the Clayton Aniline Company Manchester England described experiments showing that benzidine itself is not carcinogenic but that men exposed to benzidine excrete in their urine a hydroxylated derivative dihy- diaminodiphenyl a compound which he demonstrated does evoke bladder tumors in mice Mice were given repeated subcutaneous injections of olive suspensions of benzidine or of its hydroxylated derivative dihydroxy diaminodiphenyl Nine mice were given the hydroxylated compound and bladder papillomas developed in five and a bladder carcinoma in one No bladder tumors were found in the mice given benzidine or in control animals given injections of olive oil alone Dr. me the call to the Georgianna current work forth bladder view that its Houser Leeds University England kindly summarized for of her laboratory The curious ability of naphthylamine tumors in man and in dogs but not in other species has led carcinogenic action may depend on some metabolic change 22. King E. Clegg J. and Rac .: Effect of Asbestos and of Asbestos and Aluminium on the Lungs of Rabbits Thorax 188-197 1946 23. Barsotti M. and 129-135 for English Vigliani .; Bladder Lesions translation see A. M. A. Arch from Aromatic Amines Med lavoro Indust Hyg this issue pp 234 24. Baker K The Carcinogenic Activity of Dihydroxy Benzidine Acta Unio internat contra ca^-erum74Pt 46-51 1950 He we oe we wen me s m. e te ovec se e e oe OE we ~~ + = ce enratigwotninteo GAIT e ee 2 Bente ad 2 Came 0 ete oe ame e we 202 INDUSTRIAL HYGIENE AND OCCUPATIONAL MEDICINE 1 July 1950 a conference was held at Oxford dealing with cancer in relation to sociological and environmental factors other than occupation Proceedings of this conference have been published ABSTRACT OF DISCUSSION Dr. Paul Cartier L'Annonciation Que Canada I have been asked to describe our exigi exigi ence at the Thetford Industrial Clinic in Quebec where we see men engaged in the asbestoss asbestoss mining industry in Canada Table 3 presents data on eight cases of primary cancer of the lung which we have detected among 4,000 asbestos workers between 1940 and 1950 In addition to those listed in the table there was a case in which there was quite a definite clinical and radiological history of cancer of the lung but for which unfortunately no autopsy was performed Also there were three other cases with a strong suspicion in favor of a cancer of the lung hat for which no sufficient data are available On analyzing these anyone will be able to the asbestos factor data it seems obvious that many points would need discussion before establish a causal relationship between these pathological findings and Is it not more logical to think that the same causal factor will produce the same type of tumor and therefore why do we observe such a variety of malignant tumors Table Cases of Carcinoma of the Lungs Detected Among 4,000 Asbestos Workers 1910-1950 Putlent 4. A. 1.1 1.1 A. 1. .. G. 6. won, Years of Exposure 23 21 21 11 10 None sixmilleaut None Years in miustry 3+ 25 +5 17 NE 18 Bre ** Age Death ", 37 31 M It 14 59 65 Degies of Asbestosla Minimal Minimal Advanced None Minhmul None ..... None Type of Tunior Bronchogeole carcinoma Bronchogenic carcinoma Mediastinal lymphosarcoma with pulmonary metastasis Bronchogenic carcinoma Pleural mesotheliotna Bronchogenle carcinoina Bronchogenic carcinoma thoracotomy Pleural mesotheliumu Standard Nummenclature of Diseases and Operatioas published by the American Medical Association New York The Slakiston l'ompany 1972 suggests the term mesothelial sarcoma If for a moment we may assume that the asbestos fibers might produce a bronchogenic carcinoma in ashestutie employees with significant exposure then only two cases of the series would serve as evidence because the cases of niesothelioma or lyniphosarcoma and cases without exposure or without asbestosis do not have the conditions required . As a last remark it would appear necessary that any statistics on occupational cancer of the hu^ng to be conclusive should indicate the precise variety of lung cancer Mr. Edward A. Law New York The difference in the frequency of lung cancer in persons with asbestotie lungs as compared with the large group of silicotics provided by the Pneumoeuniasis Board seems impressive However one might wonder whether the two groups had been exammed for cancer with equal care I am impressed by the fact that when different groups or Jungs were studied by the same obsserver Dr. Gloyne the differences in frequency of lung cancer were much less we restrict our attention solely to Dr. Gloyne's series I am not sure that the duferences are statistically siemficant Die A. Lxx73 New York I think is important to distinguish between cases of clinicall recognizable and atat lung cancer in one hand and cases in which the diagnosis of lung cancer has been made as more or less of an incidental finding at autopsy on the other The English claim for an association between lung cancer and asbestosis has been hased it seems to nie on data obtained from lings that a pathologist has searched with a microscope I wonder how many 31. Conference on Geographical Pathology anil Demography of Cancer J. Nat Cancer Inst 627-662 1950 cases o same c DR cancer worke great only c Dr. E cinom to exc In silico Pneer .on to { this speriestos- _ lung finite .topsy ancer 4 . BRITISH AND EUROPEAN TUMOR PROBLEMS 263 cases of lung cancer would be found if lungs from any sort of population were subjected to the same minute scrutiny? Dr. Sit^>In regard to Dr. Cartier's query as to the significance of different types of lung cancer it may be pertinent to note that a diversity of tumors was found in the lungs of chromate workers reviewed by Dr. Anna Baetjer Experimentally the polycyclic hydrocarbons evoke a great variety of tumor types If asbestos is carcinogenic I would not expect to see it proluce only one type of tumor am interested in your observation of two cases of pleural mesothe lioma This is a rather rare tumor In examining pathological material sent us from England by Dr Hinson we found anong six cancerous ashestotic lungs two presenting alveolar cell carcinoma These tumors are often diagnosed as picural mesothelioma I should very much like to exchange slides with you In reply to Mr. Lew and Dr. Lanza it was my understanding that the English cases of silicosis and their cases of asbestosis were handled in the same general fashion through the I'nemmoconiosis Board and that the lung cancer rate found in silicoties could therefore serve as a reasonably satisfactory control for the lung cancer rate in cases of asbestosis In Dr. Gloyne's series of 81 cases of lung cancer in the several pneumoconiosis groups and in the control group the tumor was evident in the gross in all except f Some of his material was destroyed during the bombing of London but his recollection was that all of the cancers in asbestoties were recognizable in the gross Dr. John L. Poot New York Have experimental studies thrown any light on the question of lung cancer in relation to asbestosis? DR SMITH In 1941 Nordmanu and Sorge in Germany claimed to have produced cancer in the lungs of mice by exposing them repeatedly to asbestos dust Their statement that cancer had resulted in 20 of their exposed animals is occasionally quoted Actually their 20 figure referred only to two mice one of which had a type of tumor that occurs commonly as a spone taneous growth in mice The other they considered to be a squamous cell carcinoma but their photograph does not impress me as that of epidermoid carcinoma It stems rather to show merely an area of squamous cell metaplasia uld fayP y ot if .gy t tra {3 hr. Sn +