This 69 y/o male was with an abnormal chest x-ray had chest CT performed. Selected images from that CT are shown above. There is a peripheral lung lesion with adjacent pleural thickening and an anterior pleural based mass with enhancing septae. A needle biopsy of the anterior pleural based mass yielded material consistent with an abscess. Subsequent surgery confirmed actinomycosis of lung and pleura with chest wall and pericardial involvement.