Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . A subtle 4 - 5 mm somewhat rounded opacity projecting over the left mid lung may be artifactual , although underlying pulmonary nodule is not excluded . The right lung is clear . There is no focal consolidation , pleural effusion , or pneumothorax is seen . Cardiac and mediastinal silhouettes are unremarkable .
    OUTPUT:
    
Subtle 4 - 5 mm focal opacity projecting over the left mid lung may be artifactual due to overlying structures . However , underlying pulmonary nodule is not excluded . Recommend further evaluation with shallow obliques or nonurgent chest CT .