Document Dd30E2RKgrx46r0r258kGqRr5

hit. J. fndustr, Med.] i960, 17, 260. \ ]i v; * + . * 'f JstBw'VftS'F-. DIFFUSE PLEURAL MESOTHELIOMA AND ASBESTOS EXPOSURE IN THE NORTH WESTERN CAPE PROVINCE BY I. C WAGNER, C A. SLEGGS. and PAUL MARCHAND Ftom the Pathology Division, PneomoeonlosLi Research Unit ofthe Council for Scientific anti Mustrial Restart h, Johannesburg, West End Hospital, Kimberley, and the Department oj Thoracic Surgery, University of the Witwattrsrand and Johannesburg General Hospital . (REf FIVeO FOR PUBLICATION APRIL 24. I960) Primary malignant tumours of the pleura are uncommon. Thirty-three cases (22 males. II females, ages 31 to 68) of diffuse pleural mesothelioma are described: all but one have a probable exposure to crocidolile asbestos (Cape blue). In a majority this exposure was in the Asbestos Hills which-lie to the west of Kimberiej in the north west of Cape Province. The tumour Is rarely seen elsewhere in South Africa. Mesothelioma of (he pleura ii regarded as an uncommon tumour. In the last four yean we have seen 33 histologically proven cases: 28 of these had some association with the Cape asbestos field and four cases had been exposed to asbestos in industry. The tumour is rarely encountered elsewhere in South Africa. During the past five years, with the exception of the present series, no neoplasm of this nature has been diagnosed amongst 10,000 lungs examined at the Pneumoconiosis Bureau in Johannesburg, or in the Pathology Department.of the South African Institute for Medical Research. Higginson and Oettic < 1937) did not observe a single case in their survey of malignant tumours occurring in the Bantu and Cape Coloured population of Johannesburg and the North Eastern Transvaal. Our first necropsy specimen of pleural nwso-* thelioma with ssbcsiosis was examined at (he Pneumoconiosis Research Unit in February, 1936 (Case I). During the early months of that year, one of us (CA.S.) in the Northern Cape, treated six patients with gross pleural thickening. Pleural biopsies from two of (hem showed (he features of mesothelioma. In the ensuing two years, eight further cases were found from this region and five from elsewhere in the Union. During this period CA.S. had become perturbed at the number of these unusual tumours occurring amongst his patients, and stimulated an investigation. At this stage there were two reasons to suggest that asbestos might be Implicated. First, asbestos was found in the lungs of the first case (Case I), and secondly. 10 of the cases came from a hospital to which suspected cases of tuberculosis were referred from a large asbestos mining area. This hypothesis could not be supported at once from the original histories obtained from the patients, for they included house wives, domestic servants, cattle herders, farmers, a water baiiifT, an insurance agent, and an accountant, none of whom were working on the asbestos mines at the time. We therefore undertook a detailed investigation of their past occupation and place of residence, and the association with asbestos ex posure was discovered. The cases are summarized in Table 3. Previous biopsy specimens were re examined. and new cases diagnosed, including asbestos miners. In only one case do the relatives deny that the patient either visited the asbestos mines or was exposed to asbestos. This is a preliminary publication and the problem is being intensively investigated^ The Asbestos Area of the North-West Cape According to Hail (1930) asbestos was discovered by Uchenstein near Prieska during his travels be tween 1803 and 1806. Since then it has been established that the asbestos deposits extend from 20 miles south of Prieska, northwards through the western part of the magisteriol district of Hay, to (he eastern portion of the magisterial district of Postmasburg and finally, to the western area of the DIFFUSE PLEURAL MESOTHELIOMA 261 I w' district of Kimiinaftt(Fig. I). These deposits occur in the slopes of a range of hills coming an area of approximately 3,000 square miles. Known as the "Asbestos Mountains", these hills extend more or less longitudinally between 22-30" and 23" E. The whole area is semi*arid, sparsely populated, and, apart from mining, cattle ranching is the only important occupation. In the Kurdman area severed large tracts of land in or abutting on these mountains have been reserved for the aboriginal inhabitants and here whites may only reside in the immediate vicinity of the mines. The type of asbestos mined throughout this area is crocidolile, better known as Cape Blue Asbestos. The chemical un .iysis of the fibre is given in Table 1. Crocidolile is the tibrous form of riebeckite and ail stages of transformation from a massive ricbeddte rock through lamellar ricbcckite to asbeitiform crocidolile occur in this region. Magnetite is frequently associated with the crocidolile (Verraaas, 1952). Mining of asbestos first began in the Prieska district in 1693 and gradually spread northwards. In 1908 production had begun in the Kununan dis trict. Between 19)6 and 1918 a large number of claims were taken up. This northward trend has continued and in about 1950 mining started at Pomfret near the Bcchuanaland border (Table 2). Initially the ore was quarried in numerous small open cast workings. This was followed gradually Tasu 1 CHEMICAL ANALYSES OP CKOCIDOMrS AND AMOMTB Ifrixa Vraiu, IMS). i!-r, t: t i* iW:.t B* 262 BRITISH JOURNAL OF INDUSTRIAL MEDICINE . Tasu 2 fOPUlATON Ol me MAGISTERIAL DISTRICTS IN WHICH TH6 ASBESTOS FIELDS ARE SITUATED token from Union Cows 1421, and 1951) District Prisckc KsnuntA Petmuber| WfctUs ).4)0 4.71) 4.499 PtpultliM 1921 | Nenoshltsc Tool 1 4.179 ' J09 14.44$ 21,411 1 $.114 1UI) m th Htr Dbtrict Wtihn ).)$! 4.tll 2.7)7 4,117 Popatadnn 19)1 Non-whiles 21.019 , Tool 21,54? I2.JM 25.90$ by t type of shallow mining; inclined shafting be* today the non-white prefers to live as dose as came more common after 1930. possible, and the children play on the dumps from According to Frood (1915), the quarrying was a the mine and mill. family affair undertaken by the local inhabitants. The men quarried the rock, which was sorted and then hand cobbed by the women and children. Hand cobbing consists nf -separating the fibre from the banded ironstone by striking the rock cob with a small hammer. As (Ite market was selective, a Cue Histories The following eight case histories illustrate various aspects of the disease and the different types of exposure to asbestos dust. rotary sieve was sometimes used to grade the fibre Case !.--B.P., a Bantu male. 36 years of age (bom and eliminate the small particles of dust. After 1920). was a mine labourer, and was the first case .grading, it was bagged and weighed. The asbestos was then transported by donkey wagon to the nearest rail-head. Before the establishment of the railway in this area between 1923 and 1930, such a journey could last as long as 10 days. This transport was generally undertaken by white youths (farmers' sons) under contract The white inhabitants played very diagnosed as a mesothelioma with evidence cifasbcstosts. He was bom in the Kuruman district but iti is not known whether he worked in the asbestos panes. He. was employed on the WHwatcnrand gold-mines underground for two years and in the change rooms for a further 11 years. A radiograph taken at a mine hospital on August 18. 193$ showed a massive right-sided pleural effusion, little part in actual recovery of the fibre, being nearly and 3,000 ml. of fluid was withdrawn. He was admitted always employed in the rote of managers or over to the Witwatenrand Native Labour Association seen, issuing stores and supervising the grading and weighing of the fibres. Farming activities were and are still carried out round the minea. Since the 1939-1945 war. the demand for croddoIlte has enormously increased. The lucrative claim] have been bought by registered companies, others have been abandoned. As deeper and richer deposits have been found, vertical shafts are being Hospital on August 24, 1933, and two days later aspira tion yielded 1,000 ml. of thick gelatinous pus "which could be pulled out in threads". He was treated with frequent aspirations and instillation of varidase but without improvement, and he died on February 13, 1936 (Martiny, 1956). At autopsy the right thoracic cavity was occupied by a large gelatinous tumour which displaced the mediasti num and compressed th'c left lung. The tumour had Sunk. However, the mines with large shallow infiltrated the pericardium. The right lung was com deposits are still using the inclined shaft and tunnel, and quarrying is still used by the few remaining smaller producers. With the building of more mills, hand cobbing has diminished. In I'HS the first crushing mill was established at Koegas in the south. This was followed by a large mill at Kuruman pletely compressed by neoplastic tissue (Fig. 2) but the `right bronchial tree did not show any evidence of a primary bronchogenic carcinoma. Histological sections of the pleural growth showed a papillary mesothelioma (Fig. 3). There was evidence of usbeslosis in both lungs (Fig. 4). (operated between I92(> and I'fji) where it was Case 4. -K.H.. n while female. 56 years of age (bom situated within 300 yards of the main street, dose IR9B), was o social worker, who cotilil only have hnd n to which cobbing was also done for a few years (1927-1930). This was followed hy a mill at Prieska In 1930, which was completely rebuilt in 1957. Orlquatown had a small mill In 1928. The practice today is for one mill to serve several mines in the immediate vicinity. In the early days the manager and labourers lived within a few yards of their place of work, and even short exposure to asbestos ns a child and probably * further slight exposure as a young woman. She may have paid several short visits to the mines with her huxhumi at a Inter period. She wns born in (iriqualown where she lived until she was 5 years of age. Her family then moved to Kimberley where from 1916 to 1922 she worked as a clerk in nn asbestos warehouse. Her husband owned an asbestos mine from 1933-1940. *# * BRITISH JOURNAL OF INDUSTRIAL MEDICINE .. . . - .V ;A if!If! * "* :! & !***- m* vuta.* .v.* *' plfci-OnMyN.tm hi F..-Oilaty7.im i I .'J "*, \ Fo. 7.--On March 1, IMC Ftu. I.--On iaty ). 1956 T4. t, t, 1, *4 f. RMkicraplW (havtnt dMlopowM of lumour In Cm . i >v A *, s' ! I t I f A i i I t i i i I t She wjs referred co the West End Hospital, Kimberley, on July IV, 1954, because of dyspnoea and right chest discomfort of acniti onscc. The chest radiograph showed a lootluUd pleural effusion at (he right base. Siruw-coioutvd lluid was aspirated, which on examina tion was found to be negative fur At. luAercu/osIs but contained mesotheliai cells arranged in acini. At thoracoscopy in Johannesburg on August If, 1954 tumour nodules were seen on the parietal pleura. Histo logical examination of the biopsy specimen showed a ntcsodu'lioina. Deep therapy and rudio-aciive gold instillation in September. 1955 caused initial regression of both the pleural lluid and nodules but did not arrest the progress of the disease. She received a further course of x-ray therapy without improvement and died in January, 1957. The liver was enlarged and nodular before death but no necropty was done. (Pigs. 5, 6, 7, and tt show the radiological development of the tumour in this cate.) Case 14.--S.S., a Bantu male. 40 years of age (bom 1918), was an asbestos miner. He was tx>m in the Kuruman district and as a child often played on iho asbestos dump near an asbestos mine. He subsequently worked with asbestos for several years, being employed at 'an asbestos mine weighing fibre front 1958-41. \n 1942 he worked on a Witwaterarand gold mine but returned to the Kuruman district in 1943 where he worked as a farm labourer until his linal illness. He was admitted to the West End I lospital on March 3, 1959. He hud been well until July, 1958 when he became :ware of pains in the right side of his chest. In addition he had a slightly productive cough and short ness of breath on exertion. Clwst radiograph on March 9, 1959 showed obliteration of the right lung field. Asbestos bodies were found in the sputum. Needle biopsy showed histological features consistent with a mesothelioma. Autupsv.--The ritthl chest was occupied by a huge whitish tumour which infiltrated the mediastinum, extending through ihe diaphragm onto the superior surface of the liver. A straw-coloured effusion wu present in the left pleural sac but the left lung wu not affected. The mediastinal, cervical, and para-aortic abdominal lymph ghmds to the level of the.renal arterka were infiliruted with tumour. ' In the right lung it waa found that the tumour mau had infiltrated along the Interlobar litsuret. The lobee of the lung were compressed into three small segments (Fig. 9). On histological section a papillary type of pleural mesothelioma was teen (Hg. 10) which had infiltrated into the lung patenchyma in some areas. There was marked lymphatic iptyud throughout the - K i !l j l *i <i. ! 1 * 7 l J 4X 166 RRITISH JOURNAL OF INDUSTRIAL MEDICINE Jung aubxtanee. Numerous asbestos bodieswere present In (he elf spaces and occasions) bodies and fibres were seen In the interstitial tissue. The Inns itself was markedly atelectatic. I videnee of usbestosis was observed in the left lung. Gm IS.--S2J.V., a white femnle, 42 years of* age (bom 1916), is a housewife, who lived on a mine near Johannesburg and was treated for tuberculous pleurisy for six months. It was only after the histological diagnosis of a mesothelioma had been made that her previous history was ohtained. in addition, it was subsequently learnt that her father (Case 22) had been bom on the asbestos field nod had n long mining history. The patient was bom in the Griquatown district and went to school at Kuruman. She spent most of her youth in the asbestos belt. She has lived near Johannes burg for 20 years. In March, 1954 this patient developed right chest pain and rapidly increasing shortness of breath.. She was admitted to hospital and 2.500 ml. of slightly blood stained fluid was removed from the right chest. A thoracoscopic examination was carried out on July 27. when a small biopsy was taken hut this consisted of fibrous tissue. Bronchoscopy was normal and no neoplastic cells were observed in (he bronchial washings. M. tuhtrctifoiis was not cultured from numerous speci mens of sputa, pleural fluid nor from the bronchial washings. She was admitted to a Johannesburg nursing home on October 16, 195k. Radiographs then showed massive thickening of the right pleura with fluid in the right chest. At thoracotomy (Mr. Dennis Fuller) the parietal pleura was 2 cm. thick, "hard as rock" and stripped with great difficulty from the Cheat wall. The visceral peel stripped fairly easily from the upper lobe but separation became more o.fflcult over the lower lobe where the peel was thicker. During the decortication a necrotic mass was found in the paren chyma of (he left lower lobe. At (he base, confluent with the diaphragm and perhaps the mediastinum, was a hard craggy mass which could not be removed. Histological sections of the specimen revealed an adenoid form of tubular mesothelioma. Subsequently three specimens of sputum were examined for asbestos bodies but none wen found. The patient Is still alive (April, 1960), but her condition it deteriorating. Cast 22.--D.A.B., a white male, 68 years of age, and a farmer, was the father of Hie previous patient Although a diagnosis of pleural mesothelioma was made in January, 1957 it was not until July, 1959 that details of his exposure to asbestos was obtained. He was bom in Griquatown and went to school there. He worked in Kuruman, I'ostmashurg ami Griquatown until the age of 62. Between 1918 and l')2 I* worked as an asbestos miner underground and was mostly in charge of blasting. Between 19.12 and I9M he farmed in the district but returned to asbestos mining from 1945 to 1952. In January, I9S7 the patient consulted Ids doctor be cause of left-sided chest pein with cough and slight haemoptysis He was referred to the Johannesburg General Hospital for investigation. The chest radio graph showed gross pleural thickening with a basal pleural effusion on the left side. He was admitted to hospital and on June 10. 1957 a thoracoscopic pleural biopsy was taken. This showed the features of a meso thelioma. On June 24. 1957 an attempt at decortication was made. The left upper lobe was stripped easily hut the grossly thickened pleura was so adherent to the lower lobe that the attempt was abandoned. Sections of the pleura confirmed the diagnosis of mesothelioma. He died on December 13. 1937. Casa 16.--A.N.V., a white male, 50 years of age (bom 1906), was a farmer, who was bom at Griquatown and went to a village school near an asbestos mine. From 1914-16 Ik transported asbestos in donkey waggons from Hay to Prieska. During these journeys he often slept <<o asbestos bags, in 1914 he worked in an asbestos mine for a month. The patient became ill in December, 1933 with vague substernai pain and dyspnoea. A left-sided pfeural effusion was diagnosed and he was referred to Mr. J. K. Rremmer in Pretoria. There was no evidence of malig nancy in bronchial and scalene biopsies. Some apical pleural thickening and a dense homogeneous opacity at the base of the left lung was seen in thq.radiograph on August 3. 1956. Thoracotomy (Mr. Hmumerl in February, 1957 revealed a thickened nodular pleura with a large mass on (he left diaphragm. A mesothelioma was seen on histological section. In April, 1959 he was examined by Mr. J. D. Vlsser in Kimberley who found small nodules in the subcutaneous tissue over the neck and chest. A large firm mass was found in the thoracotomy wound and a mass was present in the left hypochondrium. There was generalized lymphadenopathy and numerous nodules were present on the tongue. Chest radiographs showed the left pleural cavity to be obliterated. He was one of (he few cases to develop 'widespread metastases. A biopsy of one of the subcutaneous chest nodules showed a similar appearance to those seen in the original specimen from the pleura. The patient died on May 22. 1959. No necropsy was performed. Case 24.--D.G.. a white male, 32 years of age (born 1922). by profession nn accountant, was bom in Fngtand but came to South Africa ns an infant. He spent his early childhood in Kuritmun and left at the age of 7. He later qualified as a chartered accountant in Kimberley. In 1944. at the age of 22. he had been discharged medically unfit from the army because of n left pleural effusion. Neither then nor on many subsequent occasions were acid-fust bacilli found, cither in sputum or pleural fluid. Ills only subsequent contact with ashSstos was the auditing of Ihc books of an amosite mine in the Transvaal. In September. 1951 he complained of left-sided chest pains and shortness of breath. A radiograph of the chest showed flattening of the diaphragm on Ilk* left side with obliteration of the cnstophrcnic angle and thickening of the oblique fissure. I le was seen tn numerous occasions I ~\ DIFFUSE PLEURAL MESOTHELIOMA 267 from 1953 (o I9J7. A radiograph taken early in 1956 showed the dcvclopntcnt of a left superior mediastinal shadow which enlarged progressively (Fig. II) and later the de/elopment of diffuse nodular pleural thickening ontheleft. During 1957 similar but less marked changes developed on tlw rigid'tide (Fig. 12). He consented to biopsy in June. lYJ'.-'.ind, at operation, a diffuse pleural malignancy wd present. Sections of the parietal pleura only were removed and the histological appearances were those of a meso thelioma. He died on October 6,1957. A necropsy was not performed. Case 30. -G.F., a white male, 50 years of age (born 1909), is a storekeeper, with a history of industrial exposure. He has never been near the Cape Asbestos Fields. He was born in South West Africa and lived there until the age of 21. From the age of 21 to 26 he worked In a factory in the Cape as a boiler-maker and filter. He volunteered the information that he had worked con tinuously with asbestos, lagging pipes and boilers. He remarked that the removul of usbestos lagging from old pipes created a very dusty atmosphere and (hat he would cough a lot at such work. Between 26 and 32 years of age he worked in a factory in Johannesburg in a similar capacity but was not exposed to such heavy dust con centrations. For the past 20 years he had not been in contact with asbestos. Enquiries were made from the factory in the Cape as to the nature of the asbestos used > and these have revealed that during the relevant periods Cape crocidolite was exclusively in use. He was first seen on March 14. 1959 complaining of cough, pain in the right chest and recent onset of breath lessness. Three pints of fluid had been aspirated from (he pleura and cytoiogical examination showed (he presence of malignant cells. The radiograph showed marked pleural thickening and hydro-pneumothorax. On March 17, 1959. a thoracoscopy was done. The pleura felt thickened and (he lung was collapsed and immobile. Several biopsies were taken. These showed (he presence of a mesothelioma. The underlying lung showed the presence of asbestosis. He was treated with nitrogen mustard inira-pleurally and his condition temporarily improved. When last examined he com plained of increased breathlessness. Discussion In 1924 Robertsoa denied the existence of primary malignant tumours of the pleura and con sidered them to be secondary in origin. Since (hen, on the one hand, Willis (1948,1953) and Smart and Hinson (1957) have supported Robertson's views, while on the other hand, primary neoplasms of this nature haws been described by many authors in recent yean. These include Tobiassen (1955) in Sweden, Bellom and Bovo (1957) in Italy, Godwin (1957) in the United States, and McCsugbsy (1958) I ; ; 2& BRITISH JOURNAL OF INDUSTRIAL MEDICINE In Britain. Evidence in support of the mesothelial The amount of metachromatic substance in these origin of these tumours can he found in (he tissue tumours has varied considerably. This we think i culture experiments of Stout and Murray (1942) and partly due to the fact that until recently we had not Sano, Weiss, and Gault (1950). appreciated the solubility of hyaluronic acid in The variegated histological pattern of tumours aqueous media and the majority of these tumours arising from the mesothelium of the pleura was were fixed in 10% formol-saline. Further, Lison remarked on by Klemperer and Rabin (1931). Such (1953) states that the metachromasia of hyaluronic a variation is appreciated when the multipotentiality acid is optimal ut a concentration of 1/10.000 and of the ceils lining cociomic cavities are considered. gradually decreases at higher levels. When the high Maxlmow first demonstrated this feature in 1927. concentrations that Meyer and Chaffee (1939.1940) Novak (1931) stated that the mucosa of all parts of found in their tumours are considered, this variation the Mullerian canal and Ihe germinal epithelium in metachromatic properties seems to have been were derived from these cells. Keasbey (1947) partially explained. In addition, with the great showed that in the embryo, the mesonephros, differences in the histology of the various lesions, it metanephros, Wolffian body, genital ridge, and ail would be logical to expect certain tumours with a dependent urogenital structures arc derived from marked adenoid appearance to secrete more than the mesothelium. those with an essentially nnn-giandular structure. Campbell (1950) considered the presence of both Three of the five autopsies performed showed epithelial and mesenchymal elements a major evidence of peritoneal metastases. In the other two. diagnostic feature. In describing the histology of intra-thoracic spread was observed, in one case to (he II of these tumours McCaughey(l95X) demonstrated other lung and chest wall, and in the second to the that either the epithelial or the mesenchymal clement mediastinal lymph glands and pericardium.. Biopsy might predominate. He classified his cases into (he evidence, of metastases has been obtained in two following four groups: Tumours of epithelial cases, one from the omentum and th^.othcr from the character: tumours of mesenchymal type: tumours subcutaneous (issue of the chest wall: while a third of mixed type; and tumours of anaplastic type. patient developed an implantation nodule in the Using McCaughey's classification on our series thoracotomy scar which showed a similar appearance of tumours, the majority are, as in Campbell's series, to that of the previous biopsy specimen. of the mixed type. Of the remainder, a few showed The first recorded case of carcinoma of the lung the papillary tubular structure of the "tumours of associated with asbestos was described by Lynch epithelial character", and there were several of the and Smith (1935). By 1955. according to Doll, a anaplastic type. One case had the appearances of a total of 61 cases had been reported. Included in `'tumour of mesenchymal type" but even in this case these cases was one mesothelioma. Cartier ' 1^*52) primitive tubular structures were seen. mentioned two cases of diffuse mesothelioma from a Apart from the original esse all the histological Canadian chrysotitc mine. A further three cases diagnoses were made on biopsy material. Three of were described by van der School (1958). Un these biopsy findings were confirmed at necropsy. fortunately no indication is given in the literature In the remainder, we have had to rely on clinical regarding the type ofasbestos to which the majority and radiological examination to exclude other of recorded cases of carcinoma were exposed. primary sites of malignancy. However, discussion with management and medical Following the work of Meyer and Chaffee (1939,. off on of two of the factories, in which the majority 1940), (he possibility of demonstrating hyaluronic of the cases reported in Britain were employed, acid in these tumours both chemically and histo- suggests that most of these workers were handling chemically has been considered as a diagnostic aid. chrysotile asbestos (Wagner, 1958). The possibility Both these investigations are still in an early stage that some of these people may also have been (Harington, 1959). exposed to crocidolitc dust cannot be excluded. Preliminary results of the histochcmical experi Attempts to produce tumours in experimental ments show (hat there is metachromatic substance animals by exposing them to asbestos dust have been in both the stroma ami glandular structures of the made. VurwaUt and Karr (1938) were unsuccessful. tumours. This metachromasia can he reversed by Lynch. Mclver, and Cain (1957) succeeded in pro incubation with testicular hyalumnidase. This ducing tumours in mice, but lung neoplasms in his material stains strongly with Hale's (19461 colloidal control animals were far too numerous for the Iron method. The periodic acid SchifT technique results to be considered significant. On the other has given variable reactions. These results are not hand Schmahl (1958) working in Druckrcy's specific for hyaluronic acid but are strongly laboratory has been able to produce sarcomas in suggestive of its presence. rats. This has occurred after subcutaneous and ** DIFFUSE PLEURAL MESOTHELIOMA m intrapcrrioncal inoculation of both asbestos fibres (Table 3). Eighteen of these 25 cases were born in and dust. Me states that "mineral asbestos** was the vicinity of tlte mines and two armed in the used but docs not name the variety. district as infants. Of these 18 people II admit In our series of mcsoihcliomatu, histological definite childhood exposure to the dust and two evidence of asbestosis has been observed in eight others were exposed industrially in later life, la of the 10 cases in which lung parenchyma was in* addition two patients with childhood exposure later eluded in the specimen examined. No lung tissue worked in the asbestos mines. Three cases arrived was present in the biopsies front the remaining in the region at an older age but were employed either 23 eases. It was only in the four eases that came to on (he mines or in transporting asbestos. A further necropsy that large sections of the lung tissue were three of these 25 cases lave had industrial exposure, available for examination. In all of these specimens and in only one case do the relatives deny any evidence of usbestosis was found. exposure to asbestos dust. * At first it was thought that the presence of The four industrial cases arc significant. Two numerous asbestos bodies, fragments of fibre, and of the patients, were lagging locomotive boilers and dust immediately below the pleural elastic laminae one was tagging steam pipes. A man, who was an in these specimens, might have been significant in upholsterer by trade, was employed in making the pathogenesis of the tumours. However, it is fire-proof clothing from 1939-I`M5. As far aj can more probable that this distribution is a result of the be ascertained these people were never in the marked atelectasis. Similar features have been Griqualand district. These findings tend to add observed in atelectatic lungs of asbestos miners in support to asbestos being the common factor in the which no mesotheliomas have been observed. development of these tumours, and to counter the Pleural fibrosis has been a common finding in suggestion that there may be some other environ cases of asbestosis and in some cases large pleural mental cause in the region of Griqualand Wat. plaques measuring up to 1-0 cm. in thickness have If asbestos dust is a factor in the occurrence of been seen. These plaques, which were first described these tumours, similar cases might have been ex by Gloync (1933), have been observed following pected from the neighbourhood of the Transvaal exposure to both amosite and cracidotite asbestos asbestos mines in the Pietersfciirg and Lydcnburg dusts. In these cases of benign pleural thickening districts, where crocidolite and amosite asbestos is no evidence of stromal metachromasia has been mined. According to Vermaas (1952), crocidolite observed. ' and amosite occur in the same scams in the Pieters- In all the histological sections of pleura examined burg district. As can bcscen from Table I, amosite in the cases of these mesotheliomas and in "tore is similar in composition to crocidolite. In the past than 100 cases of asbestosis. no asbeste .. .ies, four years the lungs of 24 cases of asbestosis from fragments of fibres, or dust have been observed the Lydenburg district have been examined. In beyond the pkdrai elastic laminae. this material two cases of sdeno-carcinoma have Three patients from the Kuntman district, with been observed. The one was in a white miner with clinical and radiological features consistent with 19 years' service, who had un adeno-carcinoma those of diffuse pleural mesothelioma had markedly arising from a bronchus. The other case was a abnormal cells in the pleural fluid. These cells Bantu miner who had a peripheral tumour. No showed no specific features to distinguish them from service record was obtainable in this case. Only ceils originating in secondary malignant pleural one case of asbestosis has been received from the deposits nor from the grossly utypical cells some Pietenburg area. All of these men were actually times seen in non*malignant pleural effusions. As employed on the mines at the time of death, the no biopsy or autopsy examinations were obtained in majority having hud a relatively short service. Our these cases they have been excluded from the series. findings suggest that mesothelioma occurs 20 to 40 The pathological evidence for associating these years or more after exposure to dust. Until com tumours with asbestos exposure is not conclusive. paratively recently the mining in the Transvaal As previously stated, only in eight of the 33 cases has has been on a small scale, and there were no settle evidence of asbestos been demonstrated. Of these, ments in the vicinity of the mutes. six had a definite mining history and one had been The lungs of 20 asbestos miners from the Cape exposed to asbestos while lagging steam pipes. The Asbestos Field have been examined, in whom no other case was born in the Kuruman district and moothelioma was observed. One autopsy specimen nothing else is known of him, until his arrival at a consisting of three fragments of lung showed Witwatersraml gold-mine at the age of 23. In the asbestosis and an adeno-carcinoma. Radiological remaining 23 cases we can only present circum features of asbestosis have been observed in many stantial evidence of exposure to asbestos dust miners from this region, without any suggestion of i- iv n :1. ,< *: .'.> 2* - BRITISH JOURNAL OF INDUSTRIAL MEDICINE Table 3 ___ ' DIFFUSE PIBUXA1. MESOTHPLtOMA: ASSOCIATION WITH ASBESTOS (II 6m Ha. 0) Year of Ml O) (4) 15) 14) t Kara ta Born on AibaXOd Field* < Aihlo* Espoaura (I) (9) Plifnaied on NecTopay Btopay (101 HftteWfical fiwe, Evidence of Inkle* Atbevtoale p* i 1920 V, * ilStl , 1 . 1902 ' 4 ? 19N S 1925 1901 1 1920 1 ' 1194 14 a M MXD M 51 P SI W P It 51 34 B Ww M P M 41 MXD P 9 1905 52 MXD M to im 49 M It 12 1) 14 IS tc IT ; IS . It >0 SI . 22 23 . a ' `"'if ' 29 . 2S ' ; 9S tt 12 It IMS 11991009 1911 1914 ItH tfll >920 1922 1904 >912 1909 1199 >922 >M9 IMS 1904 >199 ,`W 1911 1900 1990 40 MXD M 4S4O B M. F 40 B M 42 W P 40 W M 4S MXD P IS M 17 51 MXD W MP 44 w M <S w M 41 w P IS w M 90 w P 49 w M 52 w M 40 w M 44 50 ww M M 44 w M 49 w M 59 w P KEYS: . Column 4-- Pace: W - White MXD - Mi.edfCWoerrdl B -- same h Otter blacory unknown until ram* to tte Wft. wwMrtnnd it lh if* of 2) MlMd aibmtoa from I9M-)): UA un U tte h M*of 27 . Uvwd whoI* lift <n location mh mMhm h Uvud on ulMKN <Wd wkR tte tt; of J: worked In MbtMM wrahouad I9t4-J0_ Spent l| hh worktaf life inihevldnhy ofmine* 4 lived *11 her life In trwr vicinity of nhMt 4 lived ell M* lift hi the vldnhyof mb***: worked u e miner .. Pram ihe *f* of 24 lived In e vilief* eerrtnf loeel ndnee: often vrtited mine*: welched cobbtn eoalde houee* 4 Whole life vpem ncer mince, difxinf well* k Uvcd it (he mine from etc 7-lf yeerv played on dwnpt end in mine <i hoy: returned to tMlM (tom if* 21-25 , ...... 4 4 Whole life Ipetu neer mlnrv: mMml93l-3) Uradneecmlnaoniil'hcetcof IT; miner 1917 4 Lived neer mine uniil the efcnf 21: phyed with Abre eve child , ...... 4 Whole life epem neef minee: miner 193*-*!; ptayed on dump**** child 4 Diufhler of Ceve 22: lived el mine until efe of 20: went lo vcbool neer cobbing ehed* 4 Went lo Khooineer miner, iramponed eebeeto* 4 Lived on meior wefdn route lUI ee of 15: eevertleebeeQucnt vlehe , 4 Whole life In the vielnHy of the ndnee; miner 1943.54 4 Picnily lived el mine: miner 19)4-1979 k Spem whole life In villece on **ton raote to Kimberley t ... 4 lived In the vicinity of minee omit the am fit I#: often on domra > e child 4 Whole life In the vicinity of the ndnee; miner I91)-)2.nd 1943-32 . 4 lived In the vicinity of the mince tentll the *e - lived In the vicinity of i mill from the efe of 1-7; pleyed on Ihedumpe at e child - lived In a mlnltif ares from the efe of 10 to li yeers: after I9H apent whole life .n earns town aa Case 2 ,, .. - Mined and iremported aaheelct from 1729-55 - BoStirSorthWeatCene: traneported etbemoe from 1920-24 ,. - lived whole life on farm In minbif area from the ape of 12: trenepnrtrd aehevtoe 1914-21 ,, Mehtlainin# locomotive hmlm |9)MS - Malnlelniflf ueam pipe* tn e.pkvahw fectorke 1954-40 , ,. 0 Worked aa (liter *on railway*. meinlelnlnt loeomotlre bollrre. datre unknown Makint aebcatoa blanket* for the Air Force 19)9.45 . - No hlelory of eapowre to eabeefo* ('damn h + m Horn on teheetot (Wide -- m Not born on athevtoe fleldx 0 -- Unknown Column 9-- t -- Neciopry dona . -- Necrotny not dona * Only email freamenta of perietal pleura uibmitleil at aolopvy for hmolofical caaminatlon 4* I) stiV* SdBe** 42 3 Stifle!'** I l (2 I 41 JtB*w 13 15 4 Column 10 . -- < - pomvehr*olot"*' ofnthestoda - - No tun* tiwur lubma1" 0 - Small ftaftnawH * ^ item, but oe rvMrao sahceioah tunwur formation. However, pleural involvement has been e common finding in these case* (Hurwitx, 1939). (t is possible that (here has not been a sufficient lapse of time after exposure for tumour development in these cases. Further, the factor of individual susceptibility must also be con* *idercd. We wish re record ihc great assistance that *e haw received in this investigation from Iho medical Pf*c* tiiioncn of (he CJrkjuniund West District and the (r 4- * f (. \ l 7 l(- fj i i f I DIFFUSE PLEURAL MESOTHELIOMA 271 ihiH4CK* surgeons and pathologists in Johannesburg, Pretoria, and Durban. We itunk the Secretary of Health for permission to publish this paper. RUIKSM'U Kctlum. <. *J Box.. O. (1*57). A.tu mr.t rotor., If, 16?. Omftbcll. W. N (1950), Am,'. J. F,ik . It. 47). (tuarr. f. (1*52). An*. M^ur, rtr*, 5. 162. (CowitWiM w iM 41V.U4HM l Dull. R. (1*551 IUII. J. mtaur. AtfJ.. 12. St. FfUAt, (i. t. H (1*151. Mrmo,omtum iks ltkru.n l*L.tt,r vt th. Cuff Prituor. Kcpwit <il lh# (mhiiiiikm MmW( Umon u( South Aloe*. (K> J6-S2. S K. (1*11). fokrnUlUmJX 14.4*1 Ul. M C IW1) (WnirinU). 10. 2*1. IUtr. C. W ((*461. Nolut, <t,mJ I. 1ST. *02. Halt, A. (.. (1**0). Alhril*. w <*f Vmhm M S.mlh AttUm. Mow laiHlum n>>. 12. UculMaual Survey >> South Arm. Haiwatdx, J. S (1*5*1. PouhuI commuuicatvin. MiUmuffi J . and OcKle, A. (i. ((*571. Aitu l<4. mr. Com,.. |Ja 9(4. Httntur. M. (1*5*). rru<rf4ioti of tmirrooiumut (.fojffoc, ,4 Itfftit <M Pommtvamox". luhannaabure, Ftb. 1*5*. I'bwi.-hill. London, (la die pfn.) haaatwy. L. I-. (1*47) Amrt.J. Folk . li. 111. Ktempera. P . and Rabin. C, H. 11*11). Aw*. Pur*. (OUraovl. It. 5. Lou*. L. (1*511. ttulfrtumU rt Cnotkimit AmtmoUi. pp. 1)2.117. Cauthtce.VilIarv Par. Lynch. K M.. and Smith, W. A. (1*15). Amet. J. Coorrr. 24. 56. ------, Mctvee. F. A., and Cam. ). R. (t)7), AM.A. AftA. Imhuu. HUK 15. 207. Mantoy. O. (1*561. ftw, near, M*v rad. Ogn' Aa- 5J. 0. Miuiot, A. (1*17) Arch. f*p. 2(i(lia*S,(,), McCub*r. W. T. H*5I). J. Pm*. 4Ur,, 7*. 517. Mayar.JC.^and OuKm. E (l*>). Proe. So*. tjf, Hot. ----- .------ (t*40). J Hot. Ctfm-. 155. Alt ' Novak. fc\ <19511. Amt. J. ItPun. Umr. 22, 126, Rohcrooo. H. E. 0924). i. ( anccr Per . S, 117. Sana, M. E, Waits. IL, and Uauh. E S. (1950). /. (ten. Sm*, SebnubLD. (1*5*1. A. KtHitoni*.. 62. 561. Smart. J . and Hwao.1 K. F. W. (1957). tUU.J. Tobm^ 51.119. Stout, rt. R. and M-rray. M. ft. (1*42). Aw*. Folk. (.CUefft, TobUeacn. (li (l*55l Acte folk. (M>sa*fet wd, $ppL 105, p. I**. van da/ School. II C M. (1951). N*4. 1 Cram*. 112. 112*. Vcrmaat. F. H. S.(19*21. Traiu. ptol. S**.S. AIt~SS. 199. VoreraM. A 1., and han. I. W. U*U(. <rar. J. Path, 14.49. Wasoar. 2. C. 0*51) MfmtfooAom on Parnracmfc Hi Ktifonh te toroff. SwbmniodlolbsC^.1.11. Wttio. R. A. 0*4*. lu 6d. and 1952). Fmkoiou * Tomoon. Bunacvofth, 1-undoa. ^ Addendum By the end of June I960, a loul of 47 cue* of mesothelioma hud been KJerUitwd. In 45 of these e possible association with exposure to croridolito has been established, (a one cum a of the peritoneum wu present. .! THE JULY (1960) ISSUE i^ ; The July (1960) issue contains the following papers:-- Decompression Sickness during Construction of the Dertford Tunnel. By i*. Campbell Golding. P. Crifliths, II. V. Hempleman, W. D. M. Raton, and D. N. Walder. A Comparison of the " High-nltittide " and " Higthpressure " Syndromes of Decompression SMmaaa By M. dc G. Gribble. Phosgene Pubonjud Caused by the Use of Chemical Paint Removers ('oatalning Methylene Chloride la Khu-niilatcd Rooms Heated by Kerosene Stoves. By W. B. Gerritsen and C H. Buschmano. A Study ou the Acute Toxicity of the Tri-tryl Pboapbates Used as Phutidzm. By H. F. Bondy, E. J. Field, A. N. Worden, and J. P. W. Hughes. Aerosol Inhalation of CaNatE.D.T.A. (MosatU) by Workers Constantly Exposed to Lead Poisoning. By Li. PetroviC, M. StankoviC, M. SaviCcvi^, and D. Poleti. A Biochemical Study of the Urinary Protein of Men Exposed to Metallic Mercury. By J. C Smith and Agnes R. Wells. A Simplified Method for the Estimation of Nickel in Urine. By J. Gwynne Morgan. ' Clinical, Broncfaographie, Radiologleal, and Physiological OLiberations ia Ten Cases of AsbestosU. By - G. L. Leathart. . ^r x\ `. The Measurement of Occupational Mortality. F. D. K. Liddell. **. ' , Observations on the Occupational Life History of tbe Coal Fact orker at Two CoUieriss. By Q, p. Edmonds and O. S. Kerr. * The Aisewment of Electroencephalographlc Changes sod Memory Distwbaocee (a Acute laioxicatiooe vfl)l Industrial Poisons. By B. Chalupa, J. SynkovA, and M. Settle. >. ' ; Book Reviews. ' '' 7t'X '. A number of copies ere still available and may be obtained from the Publishing Manager, British Medical Association, Tavistock Square, W.C.l, price i7r. 6d. '[ '1; ;[ ' rrh sa * l i i t & & o f T. K i b; r