FINDINGS:
The lungs are well expanded.  There is well-defined consolidative opacity at
 the left lung base with obscuration of the left diaphragm.  The right lung is
 otherwise clear.  There is no pleural effusion or pneumothorax.  The
 cardiomediastinal silhouette is unremarkable.

IMPRESSION:
Well-defined consolidative left basilar opacity which has an unusual
 appearance for pneumonia and underlying mass may be present.  Further
 assessment with chest CT is recommended.
 
 RECOMMENDATION(S):  Contrast-enhanced chest CT.