Document DdnL4EkD14gQYyxVDoGoZNrMM

.stinum, ) be of itis and hirteen before ? accuelf felt before $ of the of the her ad; lymph bestosis allowing a and apnd dilataisbestosis, ed fibrous ved along jition and s was disembedded l the term this com- i exposure finding in ned ihages, and the same cnt, mononucled epi- fricnd that there . have ene of early jj asbestosis' J[ ,tosis. 1 PULMONARY ASBESTOSIS. V 573 the majority this is a minor finding and not the cause of illness or death; in a few the condition is advanced. Including all necropsies and all lung cancer cases, the incidence of primary pulmonary carcinoma in our necropsy service over this period is 0.3 per cent. Omitting the 35 cases showing asbestos deposits and the 2 cases of lung cancer in asbestosis, the incidence rate is 0.21 per cent. Among the asbestosis cases (35) the incidence of lung carcinoma (2 cases) is approximately 6 per cent. Whether this is to be taken as of significance, especially in comparison to the general rate, is questionable. The series of asbestosis cases is small and the possible statistical error great. It has seemed desirable, in addition, to record the observation that ad vanced asbestosis may lead to bronchial epithelial metaplasia of a type en countered in other locations where cylindrical epithelium may give rise to squamous-cell carcinoma. References 1 Lynch, K M , and Smith, W A.: Am J Cancer 24 56, 1935. 2 Gloyne, S Tubercle 17 5,1935 3. Gloyne, S.: Tubercle 18 100, 1936. 4 Egbert, D. S , and Geiger, A. J.. Am. Rev. Tuberc. 34 143, 1936. 5 Nordmann, M Ztschr f Krebsforsch 47 288, 1938. 6 Anderson, C S , and Dible, J H J Hygiene 38. 185,1938. 7 Vorwald, A. J , and Karr, J W Am J. Path 14 49,1938 8 Klotz, M. 0.: Am. J Cancer 35 38, 1939