[Dust deposits in lung tumors--cause and significance]

In the diagnosis of a so-called scar carcinoma, one of the accepted morphological characteristics is the deposition of dust in tumours of the lung. In 50 bronchial carcinomas in former miners and patients not occupationally exposed to dust, the cause and significance of such lesions were investigated in autopsy and surgical material. Impregnation with dust must be considered to be a secondary phenomenon of the infiltrative tumour growth. Such depositions depend upon previously present dust depositions in the pulmonary parenchyma and on the localisation of the tumour, and reveal a clear correlation with the histological type and degree of differentiation of the tumour.