[The role of surgery in cases of diagnostic difficulty]

Pulmonary resections for the treatment of pulmonary tuberculosis are decreasing, and nowadays most of them are for the open lung biopsy to make histological diagnosis, because differentiation between tuberculosis, AM and lung cancer is critical. In 1980-1990 forty-three patients, in whom the diagnosis was not established by conventional diagnostic methods, had pulmonary resections for open lung biopsy because of abnormal chest X-ray shadows. Of these, 31 (72%) were non-tuberculous (lung cancer 8, hamartoma 7, lung abscess 5, fungus infection 3, sclerosing hemangioma 2, bronchogenic cyst 2, and others 4, and 12 (28%) were tuberculous or AM. The type of chest film abnormality was solitary pulmonary nodule (coin lesion) in 9 out of 12 patients with tuberculosis or AM, in all eight patients with lung cancer and in 14 out of 23 patients with other diseases. In patients with coin lesions, the incidence of lung cancer was as high as 50% when the diameter was more than 21mm, while it was only 11% when it was 20mm or less. 24 patients with tuberculosis or AM complicated by lung cancer or other diseases were resected. There were 8 smear or culture positive patients with active pulmonary tuberculosis (or AM) (Group 1), of whom 7 had lung cancer and 1 pneumothorax. Of 8 patients who were wrongly diagnosed as active pulmonary tuberculosis (Group 2), there were 5 lung cancers and 3 other diseases. In the remaining 8 patients (Group 3) both old tuberculosis and lung cancer coexisted and in 3 they were found in the same lobe.(ABSTRACT TRUNCATED AT 250 WORDS)