Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Unilateral interstitial and alveolar pattern in the left lung is accompanied by left - sided volume loss and a moderate left pleural effusion . There is a suggestion of a possible left hilar mass , difficult to assess on this portable radiograph . Right lung and pleural surfaces are clear .
    OUTPUT:
    
Unilateral combined alveolar and interstitial pattern in the left lung with associated volume loss and left pleural effusion . These findings raise the possibility of a central malignancy with associated lymphangitic carcinomatosis and possible postobstructive pneumonia and atelectasis . Contrast enhanced CT may be helpful for further assessment if not already performed .