title: [The evaluation of lung cancers hidden by the mediastinal and hilar shadows on the plain chest film].
abstract: We retrospectively evaluated the plain chest frontal radiographs in four cases in which the lung cancers were quite difficult to observe prospectively on plain chest frontal radiographs in spite of the relatively large size of tumors (over 3 cm in diameter). Three of four cases were central-type lung cancers, two squamous cell carcinomas and one adenosquamous cell carcinoma. Since there was no associated atelectasis or obstructive pneumonia in these cases, wall thickening and indistinctness of the lumen of the central bronchi were the significant findings for diagnosis. One case proven to be adenocarcinoma was located in the periphery of S6. A focally increased radiopacity behind the descending pulmonary artery was the only finding to pointed out. Since tumors were not demonstrated directly in the aerated lungs, the condition of the central bronchi as well as the degree radiopacity of the pulmonary artery should be carefully interpreted.
authors.affiliation: Department of Radiology, Tsukuba University Hospital.
authors.forename: K
authors.initials: K
authors.lastname: Nozawa
authors.forename: Y
authors.initials: Y
authors.lastname: Saida
authors.forename: H S
authors.initials: HS
authors.lastname: Tsunoda
authors.forename: K
authors.initials: K
authors.lastname: Matsueda
authors.forename: Y
authors.initials: Y
authors.lastname: Kon
authors.forename: E
authors.initials: E
authors.lastname: Tohno
authors.forename: Y
authors.initials: Y
authors.lastname: Kurosaki
authors.forename: K
authors.initials: K
authors.lastname: Kuramoto
authors.forename: Y
authors.initials: Y
authors.lastname: Itai
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging; D000368:Aged; D018196:Carcinoma, Adenosquamous / Q000000981:diagnostic imaging; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D013902:Radiography, Thoracic; D012189:Retrospective Studies