A 55-year-old woman was admitted to the hospital for productive cough, mild exertional dyspnea, and fever of recent appearance. Her clinical picture, chest examination, and radiograph (Fig 1) were consistent with community-acquired pneumonia, so empirical antibiotic therapy was started, with slight improvement of symptoms.The patient had alcohol-related liver cirrhosis (Child-Pugh score A5), diagnosed 2 years before. Two hepatocellularcarcinoma (HCC) nodules (maximum diameter: 56 mm in the fifth liver segment [S5] according to Couinaud liver segment classification and 30 mm in S8) had been treated with transarterial chemoembolization (TACE) in two consecutive sessions, 12 and 8 weeks before admission, respectively. On a control CT scan performed 4 weeks before hospitalization, macronodular iodinized oil (Lipiodol; Guerbet; Aulnay-sous-Bois, France) deposits within necrotic areas were present in the cranial region of S8, along with a new 9-mm nodule in S2, whose imaging features were compatible with HCC. A new TACE was planned, when the patient fell ill. Four days after admission, the patient’s conditions suddenly worsened, as she complained of severe rest dyspnea and a piercing pain in her right-sided supraclavicular space. The right side of the chest was dull to percussion, and no breath sounds could be heard. An anteroposterior chest radiograph (Fig 2) and a contrast-enhanced thoracic and abdominal CT scan with late hepatic arterial phase and portal phase imaging, along with coronal reconstruction (Fig 3), were performed for further evaluation. On the chest radiograph obtained after the patient’s clinical worsening (Fig 2), the right lung appeared almost completely radiopaque. The coronal reconstruction of CT images (Fig 3) demonstrated a massive loculated pleural effusion, with subtotal right lung atelectasis. Floating lipiodol aggregates were present in the fluid collection. The radiopaque substance had apparently spilled out from a fissure in the diaphragm, which had an irregular and thickened appearance and was in close contact with the previously chemoembolized S8 HCC lesion. After placing a chest drainage catheter, the patient underwent surgery to restore the diaphragm integrity. During the intervention, the HCC nodule in S2, previously detected by CT imaging, was identified with intraoperative ultrasonography and was thermoablated. A histologic examination did not demonstrate invasion of the diaphragm by neoplastic tissue. The hepatic lesion was identified as a loculated sterile abscess with a fibrotic capsule deeply adherent to the diaphragmatic surface, which had developed a fistula (Fig 4). The patient’s postinterventional period was uneventful, and she was then dismissed.