Chest wall invasion by bronchogenic carcinoma: evaluation with MR imaging

The value of magnetic resonance (MR) imaging and the roles of various pulse sequences and contrast medium enhancement in detection of chest wall invasion were evaluated in 34 patients with primary bronchogenic carcinoma. Results were correlated with clinical data and computed tomographic studies. MR imaging criteria of parietal invasion included signal intensity identical to that of the tumor on T1-weighted images, intraparietal hyperintense signal of the tumor on T2-weighted images, and intraparietal enhancement with T1-weighted imaging and gadoterate meglumine administration. Twenty patients had parietal involvement, and MR imaging was positive in 18 of the 20 (sensitivity, 90%). Two false-positive errors occurred among the 14 patients without parietal involvement (specificity, 86%). T2-weighted sequences had a sensitivity of 65% (11 of 17 cases). Contrast-enhanced and non-contrast-enhanced T1-weighted sequences had the same sensitivity, but contrast medium uptake was revealed in two patients without parietal involvement. Good spatial resolution appears to be the main factor for detection of parietal invasion.