[The solitary pulmonary nodule. A retrospective study of 119 cases]

The authors review 119 cases of solitary pulmonary nodule submitted to surgery, analysing their aetiology and correlating them with their clinical and radiological aspects as well as with the patient's age, sex and smoking habits. An analysis of some pre-surgical diagnostic methods was also made. In half of the nodules (54%) the diagnosis made was of malignancy. Some of these (8%) were pulmonary metastases. There was no sex preference in the distribution of malignant or benign lesions. The average diameter of malignant nodules was 2.8 +/- 10.9 cm and benign nodules 2.1 +/- 10.9 cm. The large majority of malignant lesions was found in both upper lobes, whilst benign lesions did not have a preferential location. Adenocarcinomas were the most common primary lung tumours found, (59%), followed by squamous (27%) and neuroendocrine tumours (12.5%). Most benign nodules were benign neoplasias (43%--hamartomatous tumours) or of infectious aetiology (mostly granulomatous chronic disease--39%). The evaluation of the imagiological criteria of benignity or malignancy resulted in a sensitivity of 67% and specificity of 76%. In this study, negative respiratory cytology and bronchofibroscopic biopsies were not particularly helpful in excluding malignancy. This study confirms results published by other authors, in concluding that larger nodules have a greater probability of malignancy, that these are more frequent in males with smoking habits, and that they predominate in the upper lobes.