Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since ___ , a new well circumscribed mass - like opacity measuring 6 cm is seen in the left ___-___ region , adjacent to the operative site . Differential considerations include organized hematoma and lung torsion . Left basilar atelectasis has improved with unchanged small left pleural effusion . The right lung is clear except for basilar atelectasis . Lung volumes remain low . Mild cardiomegaly is unchanged . No pneumothorax or pulmonary edema . Previously noted subcutaneous emphysema is improved .
    OUTPUT:
    
Well circumscribed mass - like opacity in the left ___-___ region adjacent to the operative site . Differential considerations include organized hematoma and lung torsion .