Bronchioloalveolar carcinoma: sonographic pattern of ‘pneumonia’

Background: the sonographic pattern of bacterial pneumonia is predominantly well known and characterized by an air bronchogram, a marked vascularity on color Doppler sonography, and a high-impedance arterial flow pattern on Doppler spectral analysis. Methods: in a retrospective study the sonographic findings in seven patients with peripheral BAC on X-ray examination were evaluated in relation to number, size, margins, echomorphology and sonographic arterial flow patterns of the lesions. Results: the following sonomorphologic characteristics were found: multiple foci (n=4), single foci (n=3), smooth margins (n=5), irregular margins (n=2) and maximal diameter of size (range 5–15 cm). The echomorphology of the lesions was homogenously hypoechoic (n=1) or showed airbronchograms (n=6). Color Doppler sonography revealed a vascular tree pattern (n=5) or a marked presence of blood vessels (n=2). Doppler flow spectral analysis of arteries in investigated patients (n=5) demonstrates a high impedance (triphasic) flow pattern in four patients and a low impedance (monophasic) flow pattern in one patient. Conclusions: these findings indicate that BAC frequently shows a sonographic pattern of ‘pneumonia’.