Anthracofibrosis Mimicking Lung Cancer on CT: MR Imaging Findings

ABSTRACT

PURPOSE: To describe the MRI findings in the bronchial anthracofibrosis mimicking lung cancer on CT examination. MATERIALS AND METHODS: Ten patients, who showed CT findings mimicking lung cancer, were selected among fifty patients of bronchial anthracofibrosis proven by bronchoscopic biopsy, consisting of two men and eight women, ranging in age from 58 to 79 years old (average age, 68 years old). CT scan and MRI were performed in all patients(n=10). Percutaneous lung biopsy on mass was performed in one patient. MRI findings were analyzed with the emphasis on the signal intensity of the mass (n=4), collapsed lung (n=4) and lymph node (n=10) on axial T1 and T2-weighted images by two radiologists in consensus. No contrast enhancement was used in all cases. RESULTS: CT scan revealed mass(n=4), atelectasis with obstructive pneumonia(n=4) and bronchial wall thickening(n=2). All patients showed enlarged medistinal lymph nodes(n=10). The mass showed low signal intensity on T1WI and T2WI (n=4). The collapsed lung in patients with atelectasis indicated intermediate signal intensity on T1WI and low signal intensity on T2WI (n=4). Nine patients showed low signal intensity of lymph node on T1WI and T2WI, except one patient who showed central high signal intensity with peripheral rim of low signal intensity in right lower paratracheal lymph node on T2WI. CONCLUSION: Low signal intensity of a mass, collapsed lung, and lymph nodes on T2WI in anthracofibrosis patients may be helpful in differentiation of the lesion from lung cancer.