[MRI of an Intrathoracic Malignant Tumor Invading the Chest Wall].

22 patients with intrathoracic malignant tumors suspected of invading the chest wall were examined with CT and MRI. Chest wall invasion was operatively confirmed in 19 cases and excluded in the other 3 cases. CT showed tumor infiltration of the chest wall in 14/19 cases, no morphological changes in 5/19 cases. Thoracic wall invasion was demonstrated by MR in all 19 cases. Typical MR finding of malignant invasion was local lesion within the chest wall showing high signal intensity in post-Gd T1-weighted images and in T2-weighted images. Reactive inflammatory changes as well as malignant infiltration of the pleura showed high signal intensity on enhanced T1-weighted images and on T2-weighted images.