Caviation in lung cancers.

This paper examines the incidence of cavitation among tumours of the lung, the various radiological appearances and cellular types of these cavitated tumours, and the resulted of sputum cytology. Over a 46 months' period, histological and or cytological evidence of pulmonary neoplasm was found in 244 subjects whose posteroanterior chest radiographs showed opacities suggestive of pulmonary malignant disease. Of the 244 lung tumours, 220 (90%) were primary and 24 (10%) were secondary. Twenty-seven tumours (11%) were cavitated. Every cavitated tumour but one was a primary lung neoplasm. Twenty-one (81%) of these 26 cavitated primary lung tumours were squamous cell carcinoma. Large cell undifferentiated carcinoma (two cases of 7%), adenocarcinoma (one case or 4%) small cell undifferentiated carcinoma (one case or 4%) and alveolar cell carcinoma (one case or 4%) made up the rest. Sputum was examined for cells on 185 patients with primary solid and in 25 patients with primary cavitated lung cancers. Cancer cells were found in 152 patients (72%). Surprisingly, the finding of cancer cells in the sputum was no more frequent in cavitated tumours than in solid tumours. It is concluded that if a cavitated lesion in the radiograph is maglinant, a primary squamous cell carcinoma of the lung is the most likely cause. Sputum cytology performed by a competent cytologist is a very useful and simple diagnostic tool, but it appears to be no more helpful in diagnosing cavitated than in solid lung cancers.