Recent advances and perspectives relevant to the pathology of asbestos-related diseases in man.

It is apparent that progress is being made in the diagnosis of mesothelioma on the basis of morphological studies. It is also obvious that in almost every area uncertainties and deficiencies still exist. The significance of fibrous substances other than asbestos in the etiology of the various lesions is a field to be explored. The role of pulmonary fibrosis in the pathogenesis of carcinoma of the lung in those exposed to asbestos remains ill-defined. Morphological study of mesothelioma variants and imitators must continue. The accumulation of further ultrastructural data is desirable. Attempts should be made to clarify certain ambiguities in histochemical features. Recently devised staining methods and chemical, immunochemical and immunological diagnostic techniques must be further tried to establish their reliability. The utility of mesothelioma diagnostic panels seems fairly widely accepted, but persistent efforts to reconcile observer variation and to reduce subjectivity are necessary. The pursuit of immunological testing has both theoretical and practical importance. A method for the detection of susceptible persons has long been sought. The value of electron microscopy in the investigation of fibres in relation to carcinogenesis is manifest. Data is accumulating regarding fibre quantity, type and dimensions in relation to the various related lesions. The predominant role of amphiboles in the formation of asbestos bodies appears to be established. Further studies of regional distribution of fibres with their types and sizes in the lung and pleura would seem essential. Whether this will alter the concepts of the significance of exposure as indicated by analysis of the parenchymal component alone is an important question.