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Britiih Journal oj hiJiistiuil Mcdii itw, 1 974, 31, 91-104 Mesothelioma Register 1967-68 MORRIS GREENBERG and T. A. LLOYD DAVIES Employment Medical Advisory Service, Department of Employment. 1-13 Chepstow Place, London W2 Greenberg, M., and l.luyd Duties, I . A. iI974i. !hin.\h Juuiiuil n/ lucti/yinal Maliciite, 31, 91-11)4. Mesothelioma Register 1%7-hK. \ i v of mesothelioma cases is maintained by the Department of Employment. Medical Services Division (now Employment Medical Advisory Service). This paper describes an investigation of 413 notifications (o the Register in 1967-68 from I-upland anil Wales anil Scotland C ases ucre regarded as Melinite' when histological confirmation of diagnosis had been obtained, either by hospital pathologists, or by the lift Panel of Pathologists, to whom pathological niateii.il was submitted whene'er possible. Two hundred and forty-six cases wete aeceptcd as Melinite and 7(i case' weic urauled as definitely not' mesothelioma. The remainder were classified as `undecided' ot Misiillicicni pathological material'. Thirty-live of the "6 cases dclinitch not incsoihelionia had new a thclc's hcen so described oil death certifi cates. The investigation carried out covers ilmie-d aspects, survival, and evidence of exposure to asbestos. Iwche per unit of dchuiic mcsolhilioniata were of peritoneal origin. The age ranee was 21 to ,s7 years, but, in general, mesothelioma occurred at an earlier age than 'carcinoma of bronchus and lung' or `.ill malignant tumours' in the Registrar General's statis tical mortality tables. Concomitant aslvsiosis and the finding of asbestos bodies or pleural plaques occurred as frequently in those cases clussilied as definitely not mesothelioma as in confirmed cascs. Occup.itional exposure to asbestos was found in 6X"0 of definite cases, apparently signifi cantly more frequently than in those definitely not mesothelioma, but there was observer bias. The interval between first exposure and death from mesothelioma exceeded 25 years in 85 of cases but w as only three and a half years in one case. The duration of exposure varied widely; in 1,2 of cases it was under live years. The type of asbestos could be ascertained in so few cases that it was impossible to assess the role of en>eidolitc in aetiology. There were 38 I definite cases in which no history of any exposure to asbestos could be obtained. Definite mesothelioma la showed marked clustering in areas where there is substantial industrial use of asbestos, whether this should be interpreted as evidence of causation or an etfect of heightened awareness in these areas cannot be deduced from this study. Evidence is quoted suggesting that the observed annual incidence of approximately 120 definite mesothe- liomata in England, Scotland, and Wales may considerably understate the true prevalence. vfgse.'r malignant mesothelioma of the pleura and ^jgcoeum, although rare, lias been sought for in the past decade. The reported associu,f TM with asbestos exposure (Wagner, Sleggs, and Marehand, I960) gave impetus to the enquiry. For some years the Pneumoconiosis Unit of the Medical Research Council had recorded cases of mesothe lioma reported to them. By 1966 a register of some, ( em oft 1 Mesothelioma register 1967-68 93 t )"d agncr. I9M; i y 71) I'll'I to cndix. oports '.'('here on a rial to tal.cn. ter the e non* these troups: ologist, ported laparagnosit I | and --..sis of .gist to to the UlCC .re the -rial, or materia' --"|ative i *ix and at given litre the . report. containing conipotinds, or where the subject or fibres had been demonstrated by light microscopy worked in an atmosphere contaminated by asbes in sputum, lung sections, or fluid expressed from the tos dust. cut surface of the lung. The reported finding of 'Possible', where the job description was too pleural plaques at operation or necropsy, orcvidence imprecise to be certain, but there was a strong of plaques on the chest radiograph, was regarded as suspicion of exposure to asbestos. suggestive of asbestos exposure. 'Sow', where, after exhaustive enquiry, no occupational exposure could be presumed. 'Unknown', where adequate industrial details were Results i not forthcoming. If possible the duration of For die years 1967 and 1968, a total of 413 cases was exposure was recorded and the length of lime reported to the mesothelioma register. Of these, 168 before death that exposure ceased. The duration in were first notified by death certificate as having died intermittent exposures is presented as a cumulative in those years and a further 166 were notified in life figure. and died during this period. Seventy-nine subjects notified survived the period of study. Domestic exposure Death certificates were the most important Domestic exposure was considered as positive when source of notification comprising 53*5% of all a history that members of a subject's family had notifications in 1967 and 77-8% in 1968. In the come home visibly contaminated by asbestos was absence of death certifications, further notifications obtained. were received from cancer bureaux, 45 (26 5%) in I i |lobby exposure 19(i7 and 33 (13 6,,) in 1968. Further groups of cases were reported exclusively by other sources Hobby exposure was recorded in so era I house iphysicians. surgeons, and pathologists), 31 (18 2%) holders or smallholders who gave a history of in 1967 and 18 (7-4%) in 1968. Three other cases \ sawing asbestos sheeting for the constmetton of otherwise unreported were reported in each year by i outhouses, garages, and chicken houses. the Pneumoconiosis Medical Panels. A total of 170 notifications were made in 1967 and 243 in 1968. .Neighbourhood exposure Neighbourhood exposure was recorded when sub Pathological diagnosis jects lived within one mile of an asbestos factory or In Table 1 the notifications arc shown categorized shipyard using asbestos hut had no occupational according to the criteria of diagnosis. The correla exposure. tion between histological diagnosis and thediagnosis given on the death certificate was weak. Of the 246 i Other Clidcncc of asbestos exposure cases accepted as `definite', only 186 were so des Asbestos exposure was presumed in cases showing cribed tut death certificates. On the other hand, of codenee of asbestosis (either on chest radiograph or 7fi cases `definitely not mesothelioma' death had 21 necropsy ) and in those in whom asbestos bodies been attributed to mesothelioma on the death |d, but -.viewed a ere also mployer* .as made tttity or diagnosis I he final il adviser this took eceived. dclincd as 11-time or asbcstos- I A 111.1: I Not MICA I II INS III Ml Slit lit I li IMA Rll.ISltlt A'.AIYSIII IIY DlAUNOSMC CKITI.IUA AND SITE OF TUMOUR t let I'a net ! I O'.hCf [Mtlh'loglMN r I r.-di SHi' *'t iurihwt rid.a'.i l\ I HiMK'iim IMfl.K, IV'MUMicnm Picm a Peritoneum Stt text far definition Putin: is ii > 1 ,U 1'' i `i> : n: M :u> ;.ih Diilytuistu category1 UnJfi uhul Insufficient tnafrrLil u| 4 >* r-'K O) rD IJ >:j l 12 Oj 40 44 (, 1 4h i 45 Definitely not 1.1 if 42j >46 65 11 76 Total 167 28 198 20 365 48 413 94 Morris Greenberg ami T. A. Lloyd Davies certificates in 35 instances.The pathological diagnoses in these 35 cases were: Carcinoma of bronchus .. .. ,. II Carcinoma, origin unstated .. .. Secondary adenocarcinoma (primary unstated) ...................................... Not mesothelioma (no other diagnosis) Myelomatosis . . .. .. .. Transitional carcinoma of bladder . - Adenocarcinoma of thyroid .. .. Retroperitoneal fibroma or chordoma Asbcstosis and tuberculosis , . . . I Severe anaemia secondary to peptic ulcer I Malignant melanoma . . . . .. I As the concordance of diagnoses between the UlCC pathology panel and other pathologists higher than 74",', and the characteristics of the tut) groups are so similar for distribution of age at death (big. I), tumour site. sex l I able 3). anil survival (lags 3 to 4), they can be treated as one. In this study peritoneal tumour represented 12-2% of all coo- *7 JJetposur firmed mesotheliomas (Table 2). This compares men reported proportions by five authors with a ranged order u 3-7(of 80 cases) to 72-7 % (of 22 cases) (Table 3)- ^ j' to mesc From Table 2 it can be seen that the distribution of ' S, cases between the sites was similar in the group* _ Ate at confirmed by UlCC pathologists and by other S^.. The di< pathologists. is presi Terence Sex distribution of path Table 2 shows that the ratio of mesothelioma in me* anil women Tor both UlCC and other pathologist* was about 5:1, which is similar to that for malignant neoplasms of the respiratory system I Registrar General, 1970). The sex difference ifl carcinoma of the bronchus in general is thought jo pan to be due to difference in smoking habits t Hammond, 1966) but tobacco is not known to play Sx-t a role in the aetiology of mesothelioma. If it 0 toMimed that mesothelioma is related to asbestos (Ahi.i ; 246 `1 )l I INI I l.` Ml Snl III I IHM AS ANA I YNI I) IIV SEX AM) SlTE OK TUMOUR hilhohwiMx t ICC Find Other |milu>I*ij'iMs All . , ' . . . . Sift' t`J lunuHir Huir.il I'cmioihmI 1`lcnr.il IVriU'iie.il I'lcLiral PcrMtMical \fulcr ( of nil mesathvliul imtuuir*) i4 n: s'..i 10 llll'l 177 24 ii:o\> Female? (% of all mc?0~ thetial tumours) 2 18-3%) 17 4 (190%) N 6 (IJ-3M Total IIS 16 (11-9 7.3 98 14 (12523 216 30 (122*3 1 A HI 1 3 IhtivAiiNii oi Pimiiumm Mi Si'I m i him \ to I'oint-.t) tiv Variols Authors je ExpOS) . In Tab 167 (( as best either JO- 20 % to Authors Mcliwcn a al. (I97i<) . . , , Ashcroft and Mcpplcston (l()7ui . . Sclikoflrt al. (1970) .. . . Thomson (1970) .. .*. . Ncuhousc i f nl. (1972) .. .. Present study .. ,. .. Alt nit wthflitima? SO 23 11 17 1I 49 246 Prri'oncal nirsorhclivntai only {total) y (3-7 ;) y (13 0%) 16 (72 7%) 3 (17 6%) 5 (45-4%) 30 (61 2%) 30 (122%) Comment 73 males and 7 females: 2 males described as `both sites' (Scotland) Tyneside Male insulation workers (USA) Cape Town Females (London) Males from the same factory England, Wales and Scotland 1967-61 JO- C i.i: 20 A T r-: IO lo no. i ;nni xilh 'Tncc of >blc 3). .lion of groups oi her . in men ologists lor all system cnee in ught in : habits to play It' it is asbestos Mesothelioma register 1967-68 95 exposure it would be necessary to know the numbers of men and women at risk over the past 50 years in order to assess the relative susceptibility' of the sexes to mesothelioma. Age al death The distribution of age ai death of continued cases is presented in lTig. I : there is no significant dif ference between cases diagnosed by the two groups of pathologists (mean age: ItK.'C, 59 4 0-9; other pathologists. 60 2 + 1-3). Tor comparison the age distributions for all malignant neoplasms and for carcinoma of the bronchus and lung (Registrar General, 1970) arc also shown. The mean age at death from mesothelioma is significantly younger (p < 005) than that for bronchial carcinoma and `all neoplasms'. This may be due in part or in whole cither to the greater chance of identifying occupa tional cancers within the working age compared with the retired or to earlier death from mesothe lioma associated with occupational exposure to a carcinogen. Lxposure to asbestos In Table 4 it can be seen that of 246 continued cases 167 (6S%) had definite occupational exposure to asbestos and a further 29 were possibly exposed, either at work or at home. There were, however, TABLE 4 Notifications to Mesothelioma Register analysed by Asbestos Exposure Asbestos exposure his lory No, of definite mesotheliomas No. undecided, inadequate material, or definite alternative diagnoses Definite occupational exposure .. .. Possible occupational exposure . ,, .. Neighbourhood, domestic or hobby .. None - .. ,. Not obtained .. .. 167 16 13 38 12 63 17 10 57 20 still 35 (15"..) for whom careful enquiry failed to elicit any exposure whatever. In the remaining notifications (`undecided*, `inadequate material', `definite alternative diagnosis') nearly one third were without apparent exposure, and those with definite occupational history formed only 38% of the total. The differences between these groups arc significant (t* < 0-001) but may be affected by bias towards 2 males Scotland) iLSA) \ml 1967*68 JiOrj Year; 96 Morris Groonhory and A Lloyd Darios undcrdiagnusis in arcus without large-scaleasbestos industry, or to bias on the part of the interviewers who might have been more assiduous in pursuing an asbestos association history in cases oT definitive mesothelioma. Ideally it would have been desirable to conceal from interview erst lie-diagnosis in individual cases, but on account of limited manpower the interviewer may have been responsible lor identify ing cases and arranging lor coni it mat ion of diagnosis. On the other hand, the number of notifications which were not sttbsei|uenll> fully confirmed but had TAM. I 5 Ini>i:sikv ok Jon Tin t in 107 Hi i ini : i ` Mi st it tit t iosias wn > n l)i i ini u U< < i e.viii >nai Ir.M'ostiKi in Asm.sins known asbestos exposure may have been the result of over-diagnosis because of the well-known associate* of mesothelioma with this occupational history thus introducing a bias in (he opposite direction. The individual occupations of confirmed case* with industrial exposure arc shown in Table 5. The degree of risk associated with these occupation! cannot he computed because the population exposed, over a period of 50 years, is unknown and cannot even he guessed. Table 6 lists those subjects with mcsothcliont* where a history of exposure to asbestos, not occupa tional in origin, was obtained. Of those subject! wnh neighbourhood exposure, the first four lived near the same asbestos factory in a district where chest physicians have a high awareness of meso thelioma. The final four subjects listed had exposure! 30 20 IQ - IO ___ r c T0Qlhi 30 f/hlitur t (,.h \ ioh/ut of ntri.rfht fit */!,/' that might be considered minimal and conunoo experience. In cases notified to the register by the Registrar 20 Slupwiirkcr. .. Asbestos factors worker . . .insulation worker (not HilMer iumsi: "Airkcr <1101 manm-i ( he mica1 worker , Docker , , . Welding rod manufacture lhriltling worker . , 1 .lectrician , , . k cleaner rep,rrcr U elder pi tier .. flatters box manutacniif I Icctricity generating uulustrv (ias w orkcr .. .. Railway coach locomotive fuiilder Mi> 1.r nu^;h:iju^ Refuse work .. . ?s General for England and Wales a control group wi! % W established (from 1 January 1968), the next death 1 t registration matched for age and sex but not for to- area being notified to the register for comparison of 4 occupation. It was found, however, that as cases of 4 mesothelioma were more commonly referred to l coroners than were other subjects the job description was frequently qualified to indicate asbestos ex posure: for example, 'plumber' or 'fitter' was further na. 2. D v 1 categorized as 'shipyard*, whereas no such qualifica tion appeared in ihe controls. Even 'housewife'and asbestos c T widow' were recorded as occupations with the disease attributed to asbestos exposure. recognize 1 Ethical considerations prevented the interviewing (McEwen of control subjects (or their relatives) though it i* Figures known a> Occurred TARLE 6 although NnN-ncrtiPAiioNAi. Asm sms Em'oskui. IIistoriis oiitaini.o in Cases of Mesothelioma Kars am *ignificarv ( uu' nu/uhrr Durotutn of expo Nature of exposure r W A7 7(1 1 W r>M 174 IAV M IS I 'V (iS.-8(i S r,R 71 S AN A! s an-;i I av (.7 s; 1 W (,7 ns f W M IV IAV AS SS LW (,s I'M) IAV 6RTN(i I:W AN-so 75 ( c;i fs 14 years scars 22 scars Unknown 15 years 30 scars Unknown 14 vears l cn known 1 7 vears 40 vears 2 vears l -nknown 4 years 3 vears ! dav Resident within sards of an asbestos factory: at school nearby Resident close to an asbestos factory; probably went to school nearby: both parents worked in asbestos factory Worked next door to asbestos factory Resident 1 j miles from same asbestos factory Hobby: refining and relating clutches and brakes Resident 200 yards from an asbestos factory Resident < * mile from a shipyard Resident < mile from a shipyard A Resident ] mdc from an asbestos using factory Resident a. I mile from an a best os factory Resident < I mile from asbestos factory Resident < I mile from an asbestos factory Husband worked tn an asbestos factory A l is cd m a house largely composed of asbestos cement sheeting Worked on and lived adjacent to chicken farm composed of asbestos cement buildings Intermittent exposure to brother's overalls contaminated with asbestos Saw mu un asbestos cement sheets to construct two shcds_ f Chrysolite c ! Crocidoliic Amosiie on . CrociUolilc |fc. Mi*ed asbe J Type not a? Tot*l Mesothelioma register 1967-68 97 ult of -elation ry thus .1 cases 5. The pa l ions 'illation wn and licit oma iKcupasubjeets ur lived t where f niesosposurcs .ommon ^'".ictrar p w as __ 'death not for arisen of cases of erred to seription rstos ex 's further uualilica- ile- and lull the ci viewing tuyh it is carby; ^I'CMOS vshcslot UiCC portgl UlCCpongl Q*hef CQtholcqhtS Othgf ootholoqiPi iijsKKi.b-tO- N Definite mesothcfiomaswiih ikliniicoccwpntioiuil exposure: SLir\iv;il after tiist exposuic. 1 J -jeogni/ed that this would have been desirable 1 ,UcHwen, finlayson. Mair. and Gibson, I97(>). t figures 2, 2 and 4 illustrate time relationships with | inown asbestos exposure. In 85 of eases death j occurred more than 25 years after first exposure, j although the shortest period was three and a half * :ars and the longest si years. There was no j '1 . ctlilieanl ditl'erenee In llte distributions of scars of t it , Definite mesotheliomas with definite occupa tional a^eMON exposure: survival after last exposure. TABLE7 Tim i>! Asiusins ISAol M|> |V Ori'lJIXVIlONAI. A.SHISTOS EXPOSURE I f i#5i if ft\ i u; > , tonic onl> .. . .. CssiJalitv only .. .. i- "ite only .. .. . . / .tdoliu* and other .oheMos U \rd mbeMos \\itiiotii croc id due j\-< not.ascertainable . , r.-oi................................. . . , . , . . .. Dihnifr iHf.sulItt'Iiuiini 4 4 u 42 0 117 11>7 11is ttilogwai diagnosis (Jtttfccuft'tf and iitMi ffii lent material i 0 0 3 2 25 .in Definitely not Mesothelioma i i t 7 2 15 27 98 Morris Grccn/ury and T. A. Lloyd Davies : i ;. r ^ I ! r -i-i fit.. 4. Definite pleural mesothelioma: duration of occupational c\pi>'tirc in asbestos. survival after first exposure in (lie two groups (mean age: UICC, 37-4 years: other pathologists, 38-4 years). The interval between last handling asbestos and death was under otie year in about 40cases but varied up to 52 years lone case). The duration of exposure was more widely spread, ranging Trom three weeks to over 50 years. Twelv e per cent of cases had been exposed ('or under live yeat'. The man with only three weeks' exposure died osci hall a venture later. Table 7 summarizes information regarding the type of asbestos, hut this could be obtained in only a *#?!'> V). Geograpl small proportion of subjects. Of the 50 subjects wilfc 'definite mesotheliomas', where the types of asbesto* Kf-' Tables 9 to which they were exposed were known, 45 h3 million r been exposed to crocidolite. Of the group of ll subjects diagnosed as `definitely not mesotheliom*' diagnose _ The Re in which types of asbestos to which they had brf exposed were known, eight had been exposed ' 1. employe* ' Dunbart' ' Hamilto) crocidolite. '.. no meat There is no significant difference between the* two groups. In four cases of definite mesothelioma no exposure was known other than to chrysotile. A history of exposure to talc was obtained in sexto ' i western ; thousand ; 2 97 cast subjects with definite mesotheliomas, but six ol populate them had also been exposed to asbestos. It was act possible to identify the nature of the talc to whki histories ; remaindc they had been exposed. populate , only (out Other evidence of asbestos exposure asbestos It is apparent that a history of occupational exposurt to asbestos is frequently associated with the present* of asbcsiosis, asbestos fibre bodies, asbestos fibres or twice that v year- pleural plaques observed at necropsy or radiologi cally (Table 8). Ashcroft and Hepplcston (1973) stress the importance of phase contrast microscopy anil electron microscopy in searching for asbestm in tissues. The presence of pleural plaques docs always indicate asbestos exposure (Rous aid M,, Geograi '4'A ff: Studcny, 1970). It is not possible, however, to observ e a significant difference of asbestos exposurt between subjects with definite pleural mesothelioma! and those subsequently categorized as definitely nc< .pleural mesothelioma. In four`definite pleural mesotheliomas"corrobora Crvater L Rest of SI tive evidence of asbestos exposure w:as found in the absence of occupational exposure histories. Of the** subjected to 'hobby' or 'domestic' exposure (sii cases) none showed corroborative features. Of those with 'neighbourhood" exposure (eight cases), two luul asbestos bodies. SE Lanca Merwystg : Rest of N Tyneside Rest of N CoRRoiioKA'iivr TAULli S ,i m A.siu.sids l:\pi i.sure* related to Occupational Exposure History asd Niuimcaiiiins hi MisoriniioMA Rigistfr (Pleural Tumours only) ev/unur,- ht\htr\ lh-finin' pleural rftesofi clioma (\-rrflun mu c ft idl'fUC So com tfn>taii\`c tdeme Sot reported Definitely not pleural mesothelioma Corroborative evidence iVa corroborative evidence Sot reported 3E Wj f] , E An` 1}.:. ' Oydesi I Rest of SW Ei Definite .. .. Povtihlc .. . . None ascertainable . . ion tti'f.) 8 1 4 Il3",,l 24 116",.) 4 <25"..t IS (56",,) C15 4 (25 It) (3i;.) `Asbcstosis, asbestos bodies, asbestos fibres or pleural plaques 19 (73%) 0 (- ) 0 (-) 3 (127.) 3 (60%) 6 (33%) 4 (15%) 2 (40%) 12 (67 :j ` w Mil leu o Enflai 'Sum Dun One 100 Morris Greenberg ami T. .). Lloyd Davies ii TABLE 9 (b) GEOGRAPHICAL DlSI'RintlTKlN OF MeSOTHFLIOMAS ASSOCIATED WITH OCCUPATIONAL ASBESTOS Exposure and the Proportion of These Cases to all Cases of Mesothelioma fti'LMOn 1 Mesothelioma* with definite occupational ashestoi exposure So, Percentage of alt mesotheliomas (ircalcr London Rest of Si; England . . .. , .. . .. ,. 29 12 J0 67 SK Lancashire cnurH.un>n . Merseyside Conurbation . Rest of NW England , . . . . .. ... 13 22 8 81 88 too Tvneside .. Rest of N England . . .. . . ,. , . ., 8 A 89 67 VV Yorkshire conurbation ... Rest of Yorks A. Ilumhcrsijc . N WaJes..................................... St Wales .. I-. Anglia ... , . . . .. ... .. , , ,, . .. . ., ]1 2 1 6 - 92 67 _--* 33 60 _-- -- ClvdcMitc' Rest ol Scolhiul 22 . .. 3 79 50 SW England . . 18 82 E Midlands . W Midlands conurbation Rest of W Midlands .. , ., .. ., 1 4 l 33 67 (7 1 ngland, Wales A Scoiland . 167 `Siamlard regions ol Registrar lioural 1 nv.iniul A Wales, c\ccpl l' \ dc'sldc Mhinbartonshirc. Rcnlicwshiio. (irccnoik. tila-.go\s. Mamilion. Mi i herwell 68 _ * carcinoma, can poultice widexproad xhcct-like growth resembling laic slilVnsc pleural mcM'thclioma. Histologically ihc cellular a ml intercellular cliaracicrisiics can he highly ciiuivocal. The UK ( paiholoeisls panel erileria lor reaching a decision ssere muddied in Ihc course of ihc surses isce Appendix) and have not finally been decided I Met auuhcy and Oldham. 1974). Willis (1952) cautioned against accepting ihc diagnosis ol' mesothelioma until, by careful search, an alternative primary neoplasm had been excluded. In a scries of 3 771 necropsies Cameron, Litton, and Lyon (1961) found u prevalence of primary carcinoma multiplex of 12'*'. In the present series there ssere three with additional primary neoplasms In the 246 `definite' cases (one with carcinoma of the stomach, another with carcinoma of the bronchus, and the third with myelogenous leukaemia). This represents a prevalence of carcinoma multiplex of 1-2%. Sections referred lo the UICC pathologists had previously been studied by other pathologists who had not necessarily made a diagnosis of mesothe lioma. In 182 eases where adequate histological material had been studied by UICC pathologist* they made a diagnosis of mesothelioma in 134(74*3. were undecided in 10",;, and made an alternati diagnosis on 30 occasions (16 The concordance of diagnosis between UICC and other pathologists " greater in view of the fact that a number of sections were referred to the UJCC panelists for a second opinion when the other pathologists had said tbe condition was not mesothelioma but an asbestos occupation history had been obtained by the clinicians. In those cases with adequate histological material, not referred to the UICC panel (186 cases), * pathological diagnosis of definite mesothelioma was made in 112 (60%). The submission of sections to the UICC pand varied in different parts of the country. In Great' London 77 out of 111 cases were referred (69% compared with only 12 out of 61 cases in Scotian (20 %). The number of eases diagnosed is unlikely to bi Mesothelioma register 1967-68 101 TYNESIDE CONURBATION W YORKSHIRE CONURBATION logical :ogis(j native ice of ts is ions ccond id the hcstoi > the tcrial, i's), a ia n as pane) reater (,9a .'tland io be in.. 5. Gcngmphicul distribution of notifications anil confirmations of mesothelioma I9t>7-tti tstanduid regions employed by Registrar General except Clydeside which in cludes Dunbartonshire, Renfrewshire. Greenock. Glasgow, Hamilton and Motherwell): D = delinile mesothelioma --UIC C Panel; O = definite mesothelioma--other patho logists ; V - other diagnoses. J02 Morris Crccnhi-rK and /'. A Lloyd Davies tynesioe conurbation W YORKSHIRE CONURBATION m;. f'. ;ci>jjr:iplitc;iI tliviribinii*n or ilclinitc mesotheliomas ami associated occupalion.il .isbcsuis exposure: I) -- definite mesothelioma--UICC Panel; O = definite mesothelioma--other pathologists: = definite occupational exposure. oven tah patholoi underdi; These a (roup o .19 meso' patholoi only fou t The o in this s the reasi undent;- The r sbestos quoted ! teograp showed tubstan: 58 defu occupat there tumour^ In thi tsbestos three wi theliom: ire safe Unde and W. crocidol not be c Planning by all th : Employr ' merit pf astistanc , the Resii' land; H' officers . Panels w sources member the star tumours , departm slides to and oth< eiosis Ui W. R. I numbed Mr. M. Adsisor bte Dr. The foils under!o< J. D. Be T. W. D M.D. K Tombles 104 Morris (ireenlien; and /. ,1. Uovd Davies British . mcsoihc honuv r T'.f.J iwrntil >f Pntho/oy tin.i limit rinf HA% 7V77. v , Sick*! C A . aiul Marehand. r\ Dill UxC pleura! nicsiwhclt"TIM -1md ashe-vios e\|in-tire in Nt fih Western Cape r'im me e fUiltsh Jt 'tttrltll of InJll't mil Mnlu.m 17. 2 .0-271. .111! well. 1 . .mil (t.DUll He. RjJiel M 1 I'i7| |. 1 111! use m.ilijln.nill picii.i| me ' * I lie lionu .iiul .PHIhaii's ex ;h>m ire. / . 2ft. *.-2? b'rlltv U \, (i - a ; i /wt,: u| e*l.. p IlfVUe'iiwfiih, ! mu |..iilit. <*.! t>r n run:a tn (hi Hut "tifi Ictciscd tcccplcd IrT It 'r piih!u .i II.Mt ,t !nm MJi ,l*\> 17. 20. 1 *>7 ' !<>73 \ITI;M)I\ The L'lC'C. Panel of Pulliolngisls and diagnostic criteria A British panel of pathologists specialising in the diagnosis of mesotholial tumours was lormcd unofficially in 196.1 ami consisted of Dr. K. f-. \V. I tin-.on, l)r l:. Wliilwcll, I'rolessor W. I-. II. McCaughcy. and Dr. .1, C. Wagner. f rom 1961 to 1967 all cases were esamitted hy all memhers of the panel and a majotity opinion was arrived at. Suhwqucntly the panel was constituted as a UICC panel. Irom 1967 panellists decided whether the diagnosis was definitely mc'othclioma. definitely not mesothelioma or whether there was insullieient histological material, only referring material to another member or mem tiers of the panel in case of doiil'1. After inid-l90X the policy was adopted that all cases referred to the panel should be seen by at least two members and that if there was a difference of opinion a third opinion should besought. In mid-1971 the following protocol was designed for combined panel diagnosis. Two opinions arc necessary for diagnosis and these two opinions should be combined as below ; First opinion Definite mesothelioma Frohahlo mesothelioma Possible mesothelioma Not a mesothelioma If the two opinions lead to a blank entry above lb the specimen should be sent to the two Othtf readers and a combined diagnosis made on the bash ot lour readings. There are many possibilities from four readings but the combined diagnosis should follow the majority if there is a clear one and other wise be undecided. The following rule is sufficient to determine all eases of four readings; score a definite as I point, probable as {. possible as 0, not as -Ii then add up the four scores and if the total is great than or equal to 11 the diagnosis is Definite, betw - I and + I inclusive it is Undecided, less than equal to - I j is Not a mesothelioma. Addendum Mo pop min L. 0. I Departr Cancer The Mesothelioma Register, which in 1967 wd 1968 recorded cases from all available sources, hM since continued with notifications of deceased cases only. The following table gives details of notifications (subject to confirmation) for the years up to 1971. figures for the years 1967 and 1968 being included on a similar basis for comparison. x NonncAnoN.s to tiie Mesothelioma Regisii* (Death Cases) 1967-71 3 ir 0 Sources of non/n aiion 1967 !06S I960 1070 1971 r u Heath certificate Cancer Recistn.1 Indiislnu) injury data* Ollier Total 91 189 126 165 124 39 28 20 M It \ 3 6I 30 u 5 J } 163 233 157 184 111 d,sv n' 01 sr fc as `Nut so certified ut death 'Nut on death certificate or cancer registration t es ay In the short period studied it is not possible W observe a significant trend. The large number of cases notified in 1968 may have resulted from the 4;" It has bee publicity and vigilance generated by the survey. If in harmfi the impression of a falling off in notifications is con different v firmed then whether this will be due to a change ii | V pleural or the prevalence of the disease or to a change ii I;. Some evil vigilance will require to be evaluated. . from othe digestive Selikoff, ( Dchniit Second opinion Probable - Possible 1965). Cot ! ti the possib Nat fe.i' from varis ^asbestos ir Definite Deiinilc Definite Undecided Undecided Undecided Undecided Not #ihe world b My;, differences Not Not 8$ various ty, ---- - Ti, (Newhouse bvtypeofasb