2018 Volume 32 Issue 4 Pages 544-549
Case 1: A 28-year-old female was referred to our hospital for a pulmonary tumor located in the right pulmonary artery. She had undergone surgical resection of a retroperitoneal leiomyoma that invaded the inferior vena cava 4 years previously. She also subsequently underwent resection and radiofrequency ablation (RFA) for pulmonary metastases. We considered the tumor to be a new metastasis to the lung, and performed right lower lobectomy. Pathological examination revealed a macroscopic tumor embolus in the right pulmonary artery (A9+10). Case 2: A 74-year-old male was referred to our hospital for a possible thromboembolism of the right pulmonary artery. He had undergone transcatheter arterial chemoembolization (TACE) and RFA for a hepatocellular carcinoma three years ago. Extended posterior segmentectomy of the liver had been performed for S6 hepatic metastasis involving the right hepatic vein five months prior to presentation. He received anticoagulant therapy under the suspicion of thromboembolism in the previous hospital. Since the lesion had gradually enlarged, right lower lobectomy was performed. Macroscopic tumor embolus in the right A9+10 was diagnosed. Although the occurrence of a macroscopic tumor embolus of the pulmonary artery is caused by direct invasion of the tumor into the inferior vena cava, the mechanism of implantation has yet to be clarified. Differential diagnosis of pulmonary artery thromboembolism is important.
