"An air bronchogram occurs when endobronchial air is visible against a background of increased lung opacity. Expulsion of gas from the parenchyma is partial or complete and can be due to atelectasis and/or replacement by fluid, inflammatory cells, blood, tumour or interstitial thickening. The persistence of gas in the bronchi implies patency of proximal airways 6."
"neoplasms: adenocarcinoma; pulmonary lymphoma"