title: Progressive massive fibrosis in patients with pneumoconiosis: utility of MRI in differentiating from lung cancer.
abstract: Background It is occasionally difficult to distinguish progressive massive fibrosis (PMF) from lung cancer on computed tomography (CT) in patients with pneumoconiosis. Purpose To evaluate the magnetic resonance imaging (MRI) features of PMF and to assess its ability to differentiate PMF from lung cancer. Material and Methods Between 2000 and 2014, 40 pulmonary lesions suspected to be lung cancer on the basis of CT in 28 patients with known pneumoconiosis were evaluated. Twenty-four of the 40 lesions were pathologically or clinically diagnosed as PMF. The signal pattern on T2-weighted (T2W) images, post-contrast enhancement pattern on T1-weighted (T1W) images, and the pattern of the time intensity curve (TIC) on contrast-enhanced dynamic studies were evaluated. All images were analyzed independently by two chest radiologists. Results All 24 PMF lesions showed low signal intensity (SI) on T2W images (sensitivity, 100%), while 15 of 16 lung cancer lesions showed intermediate or high SI on T2W images (specificity, 94%) when PMF was regarded as a positive result. Six of 17 PMF lesions showed a homogeneous enhancement pattern (sensitivity, 35%), and 4/9 lung cancer lesions showed an inhomogeneous or a ring-like enhancement pattern (specificity, 44%). Six of 16 PMF lesions showed a gradually increasing enhancement pattern (sensitivity, 38%), and 7/9 lung cancer lesions showed rapid enhancement pattern (specificity, 78%). Conclusion When differentiation between PMF and lung cancer in patients with pneumoconiosis is difficult on CT, an additional MRI study, particularly the T2W imaging sequence, may help differentiate between the two.
authors.affiliation: 1 Department of Radiological Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.|2 Department of Radiology, Nagasaki Prefecture Shimabara Hospital, Nagasaki, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ogihara
authors.affiliation: 3 Department of Clinical Oncology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Kazuto
authors.initials: K
authors.lastname: Ashizawa
authors.affiliation: 3 Department of Clinical Oncology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Hayashi
authors.affiliation: 4 Division of Surgical Oncology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nagayasu
authors.affiliation: 5 Department of Pathology, Nagasaki Prefecture Shimabara Hospital, Nagasaki, Japan.
authors.forename: Tomayoshi
authors.initials: T
authors.lastname: Hayashi
authors.affiliation: 6 Department of Public Health, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Sumihisa
authors.initials: S
authors.lastname: Honda
authors.affiliation: 1 Department of Radiological Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Uetani
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005355:Fibrosis / Q000000981:diagnostic imaging; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000473:pathology*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011009:Pneumoconiosis / Q000000981:diagnostic imaging* / Q000473:pathology; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index
keywords: Pneumoconiosis; coal worker; lung cancer; magnetic resonance imaging (MRI); progressive massive fibrosis (PMF)