Magnetic resonance imaging of bronchioloalveolar carcinoma

The purpose of this study is to describe the magnetic resonance (MR) featur es of bronchioloalveolar carcinoma. MR examinations of 18 patients with pro ven bronchioloalveolar carcinoma were reviewed. Detection at computed tomog raphy (CT) and pathologic confirmation were the entry criteria. Nine patien ts had a solitary nodule, three patients a lobar consolidation, and six pat ients had diffuse disease. For each patient, both breath-hold T2-weighted f ast spin-echo, and breath-hold T1-weighted gradient-echo images, before and after injection of gadolinium, were available. Nine patients with pulmonar y consolidation or diffuse disease had also heavily T2-weighted MR imaging (Haste or TSE 240; Siemens, Erlangen, Germany). MR imaging showed pulmonary abnormalities in 17 of 18 patients. Unenhanced T1-weighted and T2-weighted images depicted tumor in 16 of 18 patients. Contrast-enhanced T1-weighted images showed tumor in 17 of 18 patients. In no case did MR imaging depict abnormalities corresponding to the ground-glass opacities seen on CT scans. In three patients with mucinous bronchioloalveolar carcinoma, heavily T2-w eighted images showed lesions isointense with respect to static fluid of th e human body. In conclusion, the ability of MR imaging in detecting small n odules and ground-glass opacities is limited. However, heavily T2-weighted sequences are able to show the presence of mucin. This is useful informatio n because mucinous bronchioloalveolar carcinoma carries a poor prognosis.