CT differentiation of pneumonic-type bronchioloalveolar cell carcinoma andinfectious pneumonia

The objective was to analyse the potential of CT to distinguish pneumonic-t ype bronchioloalveolar cell carcinoma (BAC) from infectious pneumonia. The study consisted of 21 patients with pathologically proven BAC and 30 patien ts with infectious pneumonia. Both groups of patients had patchy or diffuse consolidation of more than half the area of a lobe or lobes on CT. CT find ings in these two groups were compared with regard to morphological appeara nce, including CT angiogram, air bronchogram, mucous bronchogram, contrast enhancement pattern, pseudocavitation, cavity with air-fluid level, locatio n, satellite lesion, ground-glass opacity and bulging Of the interlobar fis sure. Air-filled bronchi were morphologically analysed as dilatation, stret ching, sweeping, widening of the branching angle, squeezing and crowding. L ymphadenopathy and pleural effusion were also analysed. CT findings favouri ng the diagnosis of BAC included an air-filled bronchus within the consolid ation with stretching, squeezing, sweeping, widening of the branching angle and bulging of the interlobar fissure (p <0.05). It is concluded that CT m ay be helpful in differentiating pneumonic-type BAC from infectious pneumon ia if the air-filled bronchus within the consolidation shows stretching, sq ueezing, widening of the branching angle or bulging of the interlobar fissu re.