Comparison of CT and plain tomography in hilar and lung processes

: A group of 100 patients including 46 patients with suspected bronchogenic carcinoma and 54 patients with suspected lung metastases was evaluated by conventional plain tomography. Patients with preoperatively suspected T4- or N3-categories were excluded. The diagnosis was confirmed in all cases by surgery and histology. In addition, patients with lung metastases were controlled by follow-up chest x-rays (median follow-up time 1.5 years). The diagnosis of plain tomography was true positive in 70% and false in 30%. CT was true positive in 57% and incorrect in 43%. Tumors or metastases were detected with both methods when more than 5 mm in diameter, lesions smaller than 5 mm were overlooked with CT and tomography. Plain tomography an CT did not detect lymph nodes metastases smaller than 1.0 cm.