Symptomatic pulmonary lipiodol embolism after transarterial chemoembolization for hepatic malignant tumor: clinical presentation and chest imaging findings

BACKGROUND: Pulmonary lipiodol embolism after transarterial chemoembolization (TACE) was rare and life-threatening, occasionally reported in previous literatures. We aimed to review the records of 11 patients with pulmonary oily embolism and analyze their characteristics of radiographic findings and risk factors. METHODS: Records of 478 consecutive patients who underwent 1 026 percutaneous TACE procedures were retrospectively analyzed. Eleven cases with respiratory symptoms were identified as having symptomatic pulmonary lipiodol embolism after TACE. Data of these patients, including clinical presentation, techniques of TACE, imaging features of tumor and chest imaging findings, were assessed. RESULTS: Eleven (2.3%) of 478 consecutive patients who underwent percutaneous TACE procedures had a pulmonary oily embolism after procedures. The mean size of target tumors embolized was (13.6 ± 2.0) cm. All were hyper-vascular. The mean volume of lipiodol was (21.8 ± 8.2) ml. Pulmonary oily embolisms were revealed within 12-48 hours after TACE. The most severe respiratory symptoms and imaging abnormalities of the eight patients who survived presented between 2 and 5 days after TACE, becoming normal between 12 and 35 days after TACE. Three patients died. Chest CT revealed retention of radiopaque lipiodol in lungs. CONCLUSIONS: Pulmonary lipiodol embolism occurs easily in patients who have large hyper-vascular hepatic malignant tumor. The high-density lipiodol deposition in the lung field can be used as diagnostic feature.