Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . Port - A - Cath is unchanged with its tip in the region of the low SVC . There is persistent opacity at the left lung base consistent with effusion and atelectasis . No pneumothorax is seen . Known left hilar mass is not clearly visualized . The right lung remains clear . Overall cardiomediastinal silhouette is stable . Bony structures are intact .
    OUTPUT:
    
1 . No significant change . Persistent left basal opacity consistent with effusion and atelectasis . 2 . Port - A - Cath unchanged . 3 . Left hilar mass not visualized .