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--lUirirtkar&tTim r+r'kXJtf-, 1 c h a e t IS: liti-liti, f R Vol. 1-, the concentration of er unit area, remain- ASBESTOSIS AND CARCINOMA OF THE LUNG btained in podophyl- th the absolute values nuclear water reach- i than were found in J l-a x F . C ordova, m .d., H en ry T e sl c k , m .d., a n d K e n n e t h P . K nxdtson, m .d. the water content of i of the nuclear mass, f the water increase tissue by desiccation either the cytoplasm T h e in c r ea sin g in c id e n c e of pulmonary the cases see have seen. In the review of our carcinoma has stimulated considerable own surgical and autopsy material we were .nterest in the search for possible causativaeble to find 6 cases of bronchogenic carcinoma utnts, especially those of the inhalant type. associated with pulmonary asbestosis. Five ad There aw ..ex ists .considerable data to sup ditional. cases were obtained from the files of port the contention that pulmonary asbes- the Armed Forces Institute of Pathology, :os has a definite role in the development of Washington, D.C. neoplastic change in the respiratory system. In general, the question as to whether specific C ase R eports chemistry* of Cancer. New s Inc,, Publishers. ISN7, H a w n , F. L.: Effect of r content of liver. Cancer neumoconiosis predisposes to carcinoma of the ;-jng is of considerable medicolegal impor tance, and in spite of extensive experimental and clinical research, none of the agents Case 1. P.K.E. was a 38-year-old hod carrier who had worked with insulating material for 20 years. He was a heavy smoker, A routine chest roentgenogram at Virginia Mason Hos R, A., and Hollenber, A.- ytopathology; X, measurehydrous mass, and anft'v interference microscope studied have been clearly implicated except uranium in the case of the Schneeberg miners ;a Germany. Bridge and Henry2 formulated the following specific conditions as necessary' gnant transformation of remical study with special tor the acceptance of industrially acquired tancer: (1) the rate of incidence in the occupa uieic acids - and protein- tion under* review should exceed th at in the , 1954. general population to a significant extent, id Kahler, H. [J.]: Ribo les. J. Xat. Cancer Inst. md (21 in the occupation concerned, there vculd be sufficient association of the worker mal communication. aith a substance proved experimentally to pital. Seattle, Wash., showed an unsuspected lesion in the middle lobe of the right lung. Right pneumonectomy was carried out. A white, firm, slightly gelatinous, well-demar cated, 2x3-cm. tumor was found in the middle lobe. Another small firm area was at the apex. The lesion was an adenocarcinoma with growth along alveolar walls. The stroma was denselv fibrous and contained numerous as bestos bodies (Fig. IV Of particular interest was the finding of a separate focus of tumor in the apical scar, which also contained as iorpe. A.: Magnetic suscep I transplantable hepatoma : 410-413, 1961. R R cram , C.: W ater con undergoing carcinogen rave carcinogenic properties. Although there s a statistically proved high incidence of pul monary carcinoma in asbescosis. it is readily .-parent that these postulates have not as yet bestos bodies (Fig. 2). Case 2. J.W. was a 46-year-old ironworker admitted to Virginia Mason Hospital with mild congestive heart failure. He had been a Cancer Res. 6: 574-5" been fulfilled. Indeed, it should be pointed heavv smoker for many years. A chest roent nistry of cancer tissue. / 'fnsiopathology of Catufi ml B. Hoefier, Inc.. rAV- *ut that a siudv bv |aoob and Bohlig16 indiated that the incidence of carcinoma in as bestos workers in Dresden was not increased. In view of the fan that the role of asbestosis in the pathogenesis of carcinoma of the lung remains unproved, we felt it would be worth while to review the existing evidence and present clinical and pathological findings on genogram showed a right upper lobe lesion. An exploratory operation revealed a well- defined tumor in the posterior segment of tire right upper lobe, extending through the inter lobar fissure into the right lower lobe. Pneumo nectomv was performed. A separate malignant tumor was found in tire right apex. Both tu mor nodules were surrounded bv firm areas of fibrosis. Microscopically. the tumors were ter minal bronchiolar carcinoma. There was marked pulmonarv fibrosis, and tvpieal as Fmm th e liepannw nis of JVuhoIosv. Virginia Mason bestos bodies were'found in areas of fibrosis. Hiwpiial. ItO t T e n s Ave.. Seattle 1- Wash,, the Vet- tans A dministration Hospital, and the Cniversity of "ashington Metiic.il Sdt>v!. Seattle. Wash. \Ve a re indebted to th e Armed Forces Institute of hnhologv. W ashington. P C . for their permission to -e 5 eases front rheir r.'e- and also to P r. Alexander Sttslow fo r 2 cases obtained from Firland Sanatorium, Vaule. W ash. . The photOTOurrecraohs were made bv Mr. Paul New- san. C hief of Mtxt.oal Khastration. Veterans Adminis- `Uiion H osnital. Seat:'.?. Wa-h. Received for publication Jan. 23, ISVS. Case 3. G.M.G. was a 35-year-old Negro shipyard worker admitted to Firland Sana torium w-ith hemoptysis and wheeling. A roentgenogram showed a lesion in the right up per lobe. Because of reduced pulmonary func tion. a right- lobectomv only was done. He died the following dav. The tumor measured 4X7 cm. anil projected into the apical seg mental bronchus. Microscopically, it was a 1181 f , ----- r ...T] l 11Si C ancer Xovcm vcr-Dccem h e r 1962 Vt>!_r squamous cell carcinoma with marked fibro sis of the surrounding- tissues. Numerous as bestos bodies were present in alveolar spaces and in peribronchial fibrous tissue. Case 4. H.M.G. was a 71-vear-old retired bricklaver admitted to Firland Sanatorium with suspected tuberculosis. Symptoms in cluded hemoptysis, cough, and wheezing. A large infiltrate was seen in the left upper lobe and a mottled appearance in the lower lobe by roentgenogram. Cultures were positive for tubercle "bacilli. His condition, deteriorated over a 5-month period, and he died. A poly poid. soft, white tumor in the left main bron chus was continuous with a mass in the apicalposterior segment of the left upper lobe. The tumor had infiltrated into die chest wall po>teriorlv. There was fibrocaseous tuberculosis of the right lung. Microscopically, the tumor was a poorlv differentiated squamous celt carci noma. There was moderately severe puitnonary fibrosis with numerous asbestos bodies present. There were numerous foci of caseation ne crosis associated with the tuberculous gran uloma formation. Case 3. G.J.B. was a 64-year-old white nuk pipe insulator and coverer admitted to the Seattle Veterans Administration Hospital be, cause of exertional dyspnea. He had been a heavy smoker tor 16 years previously. A chew roentgenogram showed a mass in the right lung and atelectasis of the middle and low lobes. A right lower lobectomy was carried out. and a firm infiltrating malignant tumor was found. Microscopically, this tumor was a mod erately ditferentiated adenocarcinoma that had infiltrated the mucosa of the main bronchus entering this lobe. There was diffuse fibrosis of lung parenchyma, and numerous asbestos bodies"were seen both in the tumor and in the areas of fibrosis. Case 6. H.R.H. was a 69-year-old white matt admitted to the Seattle Veterans Administra tion Hospital with svmptoms of increasing shortness of breath and chronic pulmonary dis ease. He had worked in an asbestos plant for IS years. He had been told he had asbestosis 15 years prior to his admission to the hospital. He had smoked cigarettes for 20 years. A biopsy of a skin nodule revealed metastatic anaplastic |4 f f > % r * **'*> V^ / Li 54 w.*'"** * 1 k; r- L 'W b ff1- Fig. 2. Case l. Mur x-ries: v 43i>.) Fio. J. Cjast: I. Microscopic section showing a.tU r/ri f,\s.;5 lAiimareis le^ocLattii with cor<ls of epidermoid <* cinem a of the fang. <s ^ i . ) carcinoma. Autopciuoma. arising in chus and infiltram iobe. Metastasis Hmph nodes. Ihv hestos bodies were in the adjacent fit - Case 7. >- ''ho was admit'' primary comp:-- ' 'tie of the neck 'orked as an ad*- ton Naval Ship'*- the past year v >n an asbesm* 'ears. He had Kr day for 5*' d';pnea with unction and d- to the hospitd nonary fibrf-:` |nfdr.ra'ting d ' i'Odies were y `t'g area. Case 8. P-E ho p resen tc': 'biiity and '* aken on ad- WMR Vol. i; So. 0 A sbestosis & C arcinom a o r Luxe Cordova et al. ite mal*. I to th . & pital b': - ? ! been < *%, v A che-.- aft" he rfeh* id !owe; ried out ** % -$ * ca-* >- naor wa= * ># s a mod-1 that hie ronthu- f f , '%f S '* ' i 4 fihrom asbestos and ir. y v= /<** -i ^ ^ / %VsR * - *. .& *.** ,, ? V- -*%*.*' I--'- ve-x,vi: - r , ' 4*'* **>-. <u - -*-J ms dte man ninistracreasin? nary dh- nt for fr stosis 15 ta I. He >iop$y ol laplasttc . .#*. ' .* -s : > .f ' :> < .^ 4 A > > ; S A ^ ? *Wv V - ^ g __ ________ . ...................................... ^4 *%K J fir : Ftc. 2. Case 1. Microscopic section from separate focus of the tum or in apical scar showing several asbestos bodies. (X-150.) carcinoma. Autopsy revealed an anaplastic car an area of increased density in the right upper cinoma. arising in the right upper lobe bron lobe and emphysema. A hilar mass was evi chus and infiltrating the major portion of that dent on the right. At thoracotomy, a tumor lobe. Mtastass were evident in the hilar involving the right upper lobe was found- lymph nodes, liver, and adrenal glands. As However, the tumor had, by direct extension, bestos bodies were seen within the tumor and involved the chest wall and was considered in the adjacent fibrous lung tissue. inoperable. The patient died 3 days post- operativelv in respiratory failure. The tumor Case 7. E. j.H. was a 65-year-old white man was for the most part an undifferentiated car , who was admitted to the hospital with a cinoma with areas of mucus-producing adeno primary complaint of swelling of the right carcinoma. Asbestos bodies were identified in dde of'the neck of 1 week's duration. He had both the tumor and the areas of pulmonary- worked as an asbestos insulator in the Bremer fibrosis. ton Xaval Shipyard. Bremerton. Wash., during the past vear and prior to that had worked in an asbestos manufacturing plant for 53 Tears. He had smoked 1 package of cigarettes per day for 40 years. He had progressive ihspnea with rapidly decreasing respiratory function and died 3 weeks after his admission to the hospital. Autopsy revealed severe pul* . nwwtary fibrosis with a squamous carcinoma infiltrating the right upper lobe. Asbestos bodies were prominent within the tumor-bear>ng area. Case 9. G.S. teas a 6$-year-old white man who had worked for many years with asbestos and Fiberglas as an insulation worker. His chief complaints were productive cough, ex ertional dyspnea, and weight loss. A roent genogram of the chest revealed interstitial pneumonitis in the right upper lobe. The patient showed progressive pulmonary dif ficulty with evanosis and died 10 days after admission to the hospital. At autopsy, the left lung revealed multiple firm nodules up to 1.5 cm. in diameter, anti the right lung contained Case 8. P.K. was a 62-year-old white man a firm but honeycombed area in the right who presented with symptoms of general dis apex. Sections showed a bronchiolar carcinoma .nos1. I thilhy and weight loss. A roentgenogram with multiple foci throughout both lungs and i taken on admission to the hospital revealed the hilar lymph nodes. Asbestos bodies were i.itMuujiniipmf mwmm lorraruir '17 rnBism um itm tm iii0 k ltoi>.lT>i,Mrl>MWI1TWTrf- ---*- -my. | 1154 C \ncer .\\>;r hcr-Dcct'm ber 1962 Voi. ir. So. 6 ij idemificd in the tumor aiul in areas of pul monary fibrosis. the posterior right lower emplnsema. A right lower lobe, with lobectomy diffuse showed j * ,nean durait^ jutientx was ; J i I Case 10. W.C.D. was a 60-year-old white man who was admitted to the Seattle Veterans Administration Hospital because of extreme dyspnea, anorexia, and chest pain that had been progressive during the past year. He had worked as an asbestos handler or 40 years. He had notices! hemoptysis 5 months prior to a firm but gelatinous tumor lying beneath I penn ed nu*; the pleura. Microscopic examination revealed ! lobe l6 cas a mucous adenocarcinoma characteristic of ( of cigarette . bronchioiar carcinoma. Large club-shaped as There was no bestos bodies were noted through the tu ,,onia of the . mor and in the adjacent fibrotfe pulmonan most common tissue. monia, lung 1 admission. A chest roentgenogram revealed ) densities in both lower lobes compatible with R esults 4 Ii asbestosis. A needle biopsy of the liver revealed metastatic anaplastic carcinoma. Roentgeno grams revealed osteolvtic lesions of the verte brae and skull and Paget's disease of the left innominate bone. He was given X-ray ther apy to the lungs. The pauent died on the third hospital day after progressive dyspnea. Autopsy revealed a malignant tumor appar- enth arising in the right lower lobe bronchus and infiltrating the entire right lower lobe. A o.a-cm. tumor nodule was seen beneath the pleura of the left lower lobe. The remain ing lung parenchyma was replaced by dense fibrous tissue. On microscopic section the tu mor revealed undifferentiated carcinoma with foci of necrosis. Asbestos bodies were iden Eleven cases in which asbestosis and car cinoma of the lung coexisted have been re viewed. Five cases were obtained from the Armed Forces Institute of Pathology. Washington, D.C.; among 20 cases of asbestosis on file at the Institute, an incidence of 23J. Two cases were included from the files of the Seattle Veterans Administration Hospital, Seattle, Wash.: among 6 cases of asbestosis, an incidence of 33.3^. Two cases were obtained from Firland Sanatorium, Seattle, Wash.: from a total of 6 proved cases of asbestosis, an incidence of 33^. The remaining 2 cases were from the Virginia Mason Hospital, Seattle, .Asbestos is a. of a group of. * fibrillar struct;. is found in dustries engap facturing of a.. insulating mat- millboard, wa... nets). The ptin consists of inh. Some regard of pneumocor p3nied bv sen;:- tenti should I, tified in the tumor-bearing area. Case H. G.B. was a 64-year-old white man who was admitted to the hospital with com plaints of dyspnea on exertion for 315 years. He had been exposed to asbestos and mag nesium for the previous 30 years. A roent genogram revealed a circumscribed density in Wash. Table 1 summarizes the major findings of interest in this series of patients. The mean age of the patients at the time the diagnosis of carcinoma of the lung was established was 62 years. There were 10 white patients and 1 Negro patient, all of whom were men. The clinical manih' velopment of icterized by fib:- so-called asbesi - tion and degree Lynch18 proei^ pathogenesis of into 4 stages. 1 Table 1 1 to 15 years' a CASE HISTORIES OF 11 MALE PATIENTS WITH .ASBESTOSIS AND LUNG CANCER symptoms for r siderable ind, Case Pt. no. init. Pt. Durt. age, Pt. expos. vr. race vr. Smoking history Occupation Site ca. Type ca ity, some ind rapidly while c i P.K.E. 2 JAV. 58 w 46 w 20V 2 ok..dav 20 vr. 2 ok. day ? yr. Hod carrier Ironworker Rt. mid. lobe Adenoca. Rt. upp. lobe Term." i 'rithout evidtn Vrnptoms of :: i I bronchioiar 3 G.M.G. 55 N 5 y Shipvard worker Rt. upp. lobe Srjuam. cell 4 H.M.G. 71 5 G.J.B. 64 Wi r 40 1 ok. "dav ? vr. 30 2. pk. day 10 Ret. bricklaver Pipe Ihsulator Lt. upp. lobe Scptant. celt Rt. low. lobe* Adenoca. rough with e\ palpitation, wt.. Characteristic \ r.: stopped 8 yr. prior to death 6 H.R.H. 69 w 48 1 pk. day 20 yr. 33 yr. in asbestos Rt. upp. lobe Small cell he seen on roe: The pathog mfg. & 16 yr. as asbestos insulator 7 E.J.H. 65 w 40 1 pk. 'day 40 yr. S3 yr. in asbestos Rt. upp. lobe WelWiff. found in the i the lung and in ' mfg. souatn. cell nodes.'1-13 The 8 P.K. 9 G.S. 62 vv None 68 w kno>wn None 30 yr. Carpenter Rt. upp. lobe Undin. Insulation worker; worked with R t upp. lobe Term. bronchioiar fent fiber, IOf to diameter, er 'tusted sheath 10 W.C.D. 60 11 G.B. 64 u* w Fibergtas many T* 40 30 11 ok./dav 46 vr. Asbestos handler Rt. low. lobe Cr.diff. y Occupat. expos, Rt. low. lobe Term. to asbestos & bronchioiar magnesium 'ornpound. TV 1he fibers ma' : '* giant cells. 3 ; the deposition - Yoj. X * ' a J- A sklsiosis & C arcinom a a t Lt.xc Cordvia el al. 1185 er lobe, with diffuv -er lobectornv show;' tumor lying berms- examination revea>.-'. tna characteristic c; .arge club-shaped a* I throughout the tut fibrotic puimonan carati o n o f o s '. e r .e s w a s 5 5 v e a most< ; , : u r r e - i fre o -~:)y in the right upper , re cases . J y patients had a history : g a r a o t e s m ro i f r . :or 20 years or longer, There was no prei -''inant cell type of carci- .-rra oi the 1ur-g :zi oar series. Death was r-'-str r - '- s ccocmomntonlry at-tributed to bronchopneu- r-oria, lung abscess, and cor pulmonale. gress even after exposure to inhalation has been discontinued. The exact nature of the association be tween asbestosis and pulmonary carcinoma has been difficult to unravel. Since the first report by Lynch and Smith,21 many observations have been made concerning this relation ship,4- Vi U with the use of several different approaches to the problem. It has been shown in a series of studies that D:scrs>iox there is a statistically proved higher incidence ibeuosis and car ed have been re .Asbestos is a magnesium silicate that is one Stained from tht a group of silicon minerals of crystalline >. Pathology, Uadi- brlilar struaure.-i Industrially, the material 'a>c-5 of asbestosis on incidence of 25T. : t'o'jnd in asbestos mining and in many in* iu-tiies engaged in the processing and manu from the files of the istration Hospital, sses of asbestosis, an facturing of asbestos products. These include insulating materials re resistant cloths, ropes, rtiifboard. wallboard. mortar, and other prod cases were obtained n, Seattle, Wash: ses of asbestosis, an taming 2 cases were Hospital, Seattle. ucts . The principal hazard in these industries consists of inhalation of the asbestos dust. Same regard pulmonary asbestosis as a form si pneumoconiosis not necessarily accom panied by symptoms, whereas others feel the term should be reserved for cases in which of carcinoma of the lung in patients with as bestosis than in the general population. One such study, the results of which are given in the .Annual Report of the Chief Inspector of Factories for the Year 1947 in Great Britain, established that carcinoma of the lung occurs in 13% of cases of asbestosis in contrast to the 2 to 6% incidence in the general popula tion. Doll,4 in similar studies, arrived at the con clusion that the risk of developing carcinoma of the lung was higher In individuals exposed for a long period of time to asbestos inhala tion. Xordmann,23 who published data on 6 cases, went even further to state that card major findings of atients. The mean me tire diagnosis of established was 62 te patients and 1 n were men. The T ` clinical manifestations are present,25 The de velopment of pulmonary lesions that are characterised-by-fibrosis and the formation of the so-called asbestos body depends upon the dura tion and degree of exposure to asbestos dust.5 Lynch15 provided a careful description of the pathogenesis of the disease and classified it noma of the lung is an occupational disease among people engaged in asbestos work. This opinion was also expressed by Homig.12 The second point of interest concerns the multifocal development of cancer in these cases pointed out by Xordmann.23 Gloyne,8 and Hueper.13 This feature has often char into 4 stages. The lesions may appear after acterized the malignant tumors found in as 3 to 15 years' exposure but may not produce bestosis and has also been noted in 2 of the XG CAXCER symptoms for manv years.13 There is con cases presented in this report. siderable individual sanation in susceptibil Finally, the age-time exposure relationship ity, some individuals developing the disease has supported die idea of a causal relation :a. Type ca. rapidly while others raav be exposed for years ship. The longer the exposure to asbestos, the lobe Adenoca. without evidence of pulmonary involvement greater the risk of developing a malignant lobe Term. bronchiolar lobe Squam. cell lobe Squam. cell lobe Adenoca. Symptoms of the disease consist of dyspnea, cough with expectoration, pallor, cyanosis, palpitation, weight loss, and chest pain.24 27 Characteristic changes of pneumoconiosis may tumor: and the younger the individual when first exposed to asbestos dust, the earlier is the development of the pulmonary- carcinoma. However, this relationship is not invariably be seen on roentgenographic examination. found. lobe Small cell The pathognomonic asbestos bodies are As shown in the cases presented. 4 of the fount! in the interstitial connective tissue of individuals had no known history of direct lobe Well-di. ihe lung and in peribronchial and hilar lymph exposure to asbestos dust, and the diagnosis of squam. cell tobe indiff. nodes.*-13 They consist of a central translu asbestosis was made based entirely on the cent fiber, lfl to 100 u in length and 1 to 12 u histological findings of pulmonary fibrosis as obe Term. bronchiolar in diameter, enclosed in a golden-brown en sociated with the presence of asbestos bodies. crusted sheath composed of an iron protein There are no documented cases in the litera compound. T he ends are usually bulbous. ture to our knowledge of cases of asbestosis >be I'nditf. 'be Term. bronchiolar The fibers tnav be surrounded by macrophages associated with carcinoma of the lung in which <vr giant cells. The fibrosis that accompanies the patient had not been exposed at one time (be deposition of asbestos fibers tends to pro or another directly to asbestos dust, either in >\iV am tt 1S6 C ancer X o v c rn b c r-D c c c m b c r 1962 Vol, V'. the mines, in the crude processing of the fibers, or in other phases of the manufactur ing-*- ll' 11 However, it is well known that asbestos is now being utilized to a greater degree in the manufacture of products that patently bear no direct relationship to asbestos, such as in insulating material, rope, wallboard. mortar with cement, and plaster of paris. If we accept the cases presented as asbestosis. then these individuals, even though known exposure is lacking in the history, have been exposed to asbestos dust in some form and for prolonged periods of time to induce changes compatible with asbestosis and the subsequent development of pulmonary carci noma. The fact that no known exposure ex isted in 4 cases indicates that the disease can occur without prolonged exposure to known sources. The average time lapse from the ini tial exposure to asbestos dust to the develop ment of asbestosis is 9 years according to Egbert and Geiger,5 although this figure varies according to different authors, and much shorter exposure times with development of asbestosis have been recorded. In individuals who have developed carcinoma of the lung, the asbestos exposure time averages 15 years, with a range of 3 to 27 years.131* and with latent periods of from 15 to 22 years between the initial exposure to the asbestos dust and the development of a malignant tumor.3 There have been cases, however, in which an unusually short exposure time was re corded. In a case cited by Owen,24 pulmonary carcinoma developed in an individual exposed to asbestos dust for only 12 months, approxi mately 20 years after the exposure. The majority of the lung carcinomas as sociated with asbestosis recorded have been of the squamous cell type. In our series, bronchiolar carcinoma and undifferentiated carci noma were present in equal numbers. Localization of the tumor in these cases is of some interest. Carcinoma of the lung usu ally occurs more frequently in the upper lobes, whereas in asbestosis, approximately 80% of the cases reported occurred in lower lobe where tire pneumoconiosis is most severe. ! ; jfbestosis. Tut1,, . V Gloyne. S. % occurring , Our cases showed a majority of the malignar. 1 :.ltd. tumors occurring in the upper lobes (Tab j a Great B*m;- . val Service; a*, 1). " t ; Factories ter u . Other agents that are believed to be relate; Vtncsts's Sutiow*, , to cancer of the lung are uranium, chromiurr j and possibly nickel. In the case of asbesto j 10. Hollis. H i ,irinouia in a, V-i-vort of 2 caws although experimental proof is lacking, then ' 11. HOMECSr.tl ! appears to be sufficient clinical pathologies I noma of loop evidence to make it highly probable that th is a carcinogenic agent.2 it must be admitted crature and rtj. h>7, 1943. 12. HORNtc., F t that the carcinogenic stimulus is a weak one. , BerufskrcW and the mode of action is still obscure. Par tid e size is apparently of importance in the `0rsch. 47: SS1-2-13. H ie t , \s ; Diseases. Spring production of asbestosis. Those fibers less thar. r o. 403-405. 20 u in length have no apparent deleterioueffect.15 The fibrotic reaction in the lung i? 14. Hvrrt*. jndust. Med. 29 < 13. ISSOLBACMI v produced by both phvsical and chemica'. Asbestosis and i changes secondary to the asbestos fiber.5 :: autopsied case a- The fibrosis is a progressive phenomenon, with progression after exposure has ceased.11 I j.M ed . 13: 72i : 16. Jacob. G- Besonderheitcit Multifocal areas of metaplasia of the bron- Arch. Ceteertej* chiolar epithelium have been described in the areas of fibrosis and the suggestion made that these represent early stages in card oogenesis.2 The silicate portion of the fiber is apparently not responsible- for this activity. Carcinoma of the lung occurs in only 1.3% of cases of silicosis in contrast to 13% in cases of asbes tosis.4-14-15 It has even been suggested that silicosis may be a deterrent or even offer pro tection against carcinoma of the lung. StMMARV Eleven cases of asbestosis assodated with carrinoma of the lung are presented. A known exposure to asbestos dust was obtained in 7 of these cases. In at least 2 cases, evidence is <v-;cribed for multifocal origin of the tu mor. Typical asbestos bodies were identified in the tumor-bearing area Of the lng in each case. The possible relationship of asbestos bodies as a cardnogen in the production of cancer of the lung is discussed. REFERENCES t. An m w jv . J.. and C smpacss. F. A_r Asbestosis and carcinoma of lunz; case report and re few of literature. Aren. E ntiren. H . I: 27-32, 1960. 2. Barer,k. j. c ., and H enry. S. A.: Irt-du-trial can cers. In Report of the interna tier.:; I Oor.rerence on Cancer. London. i7tf>-29th Julv. K-2.2 more. Md. William Wood * Company. 122- p-p 2-:-2. 3. O-baton, R. J. R.: Vjuamom v .~ carcinoma oc cmururi.ng in asbestosis of Iun;r'. Brit. f . C.-l.-ss." 2: 2 SC*273. 4. Doll. R.: M ortality from lung cancer in asbestos workers. Brit. J. In d u 't. Med. 12: l-86, 1935. 5. Eobekt. D. S.. and G iscat, A. J.: Pulm onary as bestos:s and carcinoma; report of case with necropsy findings. Arr,. R e t. Tubtre, 14: 113-179. 1933. 6. G srovr.p, L. C,, and CuMvrrNos. D. E.: Studies on experimental pneurnonoioniosis: inhalation of as bestos dust; its effect upon prim arv tuberculous infr-ctiotv / . I n d u i t . H ',z. 13: 65- l. 1931. 7. Gloyne, S. R.: Morbid anatom y and histology i Vor va 6 .Asbestosis & C arcinom a o f L e w * Cardava et nt. 1187 Fred in lower Io> f asbestosis. Tubercle 14: 445-451, 193$, *** is most sever:. ry of the maligns- ?. Cuar.vE, s. R.: Ca>c of oat te ll carcinoma of ,r,g occurring in asbestosis. Tubercle 1%: 100*101, -36. upper Jobes r i a l Great f i r n e r - . M m s itv o r I.sroi.r tv a .Na- -ONCt Sj>.\r-.i,: A nnual Report of the C-hief Inspector elieveci to fee relar: f Factories for th e Year 1047. London, Lnglarjc!. His .isfestv's Stationery Office. 1019. ' cranium, chromiu.-. H oLtra. H. B_ and Ancrmt. A. A.: Bronchogenic be case of asbesto arcinoroa in astotiation with pulm onary atbettosis; oof is lacking, thr j -port of 2 cases. 'l l , Hovfc'.aor*, -4*n. / . Rein. 1; F.: Co-incidence 125-135, 1942. of primary carci- ilnical patfeoiogio ! a a of lungs and pulmonary asbestosis: analysis of probable that't.1 _:trature ar.d report of 3 eases, Am . / . Rath. 19: 797- t must be admits alus is a weak or., -:*7. 1943. 12, Horsio. F.: Klinische Betrachtungen zur Frage :es Berufskrehses der Astestarl<eiter. Ztschr. Kre& - still obscure., J>, 47; 2e j - 27, 19?;- importance in th ose fibers less thsparent deleterio*, n in the lung al and chem/ca asbestos fib e r J--' n*e phenomenon, sure has ceased." `a of the bron t described in the 1$. H u f . W, C.: Occupational Tum ors an d Allied Diseases, Sprinrfield, 111. Charles C Thom as. 1942: :p. 403-405. ' 14. H lepep. W . C.: Environm ental lung cancer. ; dust. Med. 20: 49-62. 195!. 13- issiXBACHtR. K. Kt-vcs, H., and Hardy. H. L.: Asbestosis and bronchogenic cardnom a; report o f 1 ..toosied case and review of available literature. A m . Med. 13: 721-732, 1953. 16. J acob, G., and Bohuc, H.: b e r Hufigkeit und Besonderheiten des Lungenkrebses bei .Asbestose. J'rh. Geu-erbepath. tr. Geerbehyg. 14: 10-28, 1955. estion made that cardnogenestV ber is apparenti vity. Carcinoma --3% of cases o: n cases of asbes- ! suggested that even offer pro- the lung. 17. Lear.ACH, A. J-, and Wj_w.n!. H . W.: Beitrag rum Berufskrebs der Asbestarbeiter. Virchows Arch, path. A nei. 307: 387-492, 1910-1941. 1?. L ynch, K. M.: Pulmonary asbestosis; asbesto bodv and sim ilar objects in lung. / . d . V. A . 109: 1974 1973,1937. 19. Lynch, K. M.: Pathologe o f asbestosis. Arch. M u s t . f f . 11: 185-188, 1955. " 20. Lynch. K. M., and Prvtt-Thomas, H , R.: Car d n o m a of lu n g la asbestos; rep o rt of. 2 additional cases. Youth. M. / . 4s: 565-509, 1955. 21. L ynch, K. XL, and Smith, W . A.; Pulmonary asbestosis H i; cardnom a of lung in asbesto-silicosis. A m . J. Cancer 24: 56-64. 1935. 22. L ynch, K. M., and Smith, W. A.: Pulm onary asbestosis; report of bronchial carcinoma and episneiial metap'iana. vfri. / . Ccncer 55:' 567-573, 1939. 2$. Nordmaw. XL: D er Berufskrebs d e r Asbestar beiter, Ztschr. Krebsforsch. 47: 238-302. 1933. 24. O wen, T . K.: C ardnom a and asbestosis of lung; report o f esse. B n t. J. C om er 5: 352*353, 1951. 25. Sander. O . A.: Asbestosis as differentiated from oth er pneumoconioses. Arch. Indust. H . 11; 208*211, 1953. * 26. Stoia. R-: Bass. R ,, an d Anorist, A. [A.]: As bestosis assodated with bronchogenic cardnom a. A . M . A . Arch. In t. M ed. 88; 831-834,1951. 27. W iese, E, R., and H au.. W. E. 8 .: Asbestosis; re po rt of case. DCs. Chest 30: 229-230,1956. ssodated with Totted. A known * obtained in 7 ' 7ases, evidence gin o f the tucere identified o lung in each p of asbesto production of weer in asbesto 86, 1955. P uIntonar- j. with necTtsps 1936. D . E.: Snider halation of * u b erai Ions in and histol.-c