Pleural granulocytes with cytoplasmic inclusions from patients with malignant lung tumours and mesothelioma.

Granulocytes with cytoplasmic inclusions (RA = Rheumatoid Arthritis cells) have previously been found in pleural effusions of rheumatoid and tuberculous origin. We now report the finding of RA-cells in effusions from patients suffering from bronchogenic carcinomas of the squamous-cell type and malignant mesothelioma. Such cells occurred only rarely in other types of primary or secondary lung tumour.