A 78-year-old man with three prior malignancies was referred to our institution for further evaluation of a hilar mass. He had been diagnosed with large B-cell lymphoma 12 years prior to his presentation to our institution. Two years after the diagnosis, the patient had been diagnosed with prostate adenocarcinoma and melanoma of the ear. Eight months prior to his presentation at our institution, the patient was seen by his local physician for persistent back pain. A thoracic spine-computed tomography (CT) showed a pathologic fracture of T-4 vertebra that was associated with a soft tissue mass as well as a hilar mass. An abdominal CT revealed a mesenteric mass and biopsy showed large cell lymphoma. The patient received palliative radiotherapy to the spine and chemotherapy. A restaging positron emission tomography (PET)-CT scan revealed a persistent hypermetabolic hilar mass.
The patient then sought consultation at our institution. A CT scan showed a 5-cm mass involving the right main pulmonary artery. A PET-CT scan showed a hypermetabolic mass involving the right perihilar space [Figure 1]. The patient was referred for an endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) with ROSE. The findings were in keeping with a PAS. Subsequently, the patient underwent preoperative chemotherapy followed by resection of the right pulmonary artery tumor with reconstruction, followed by a right thoracotomy. Two months later, a PET-CT scan revealed a fluorodeoxyglucose (FDG)-avid mass within the right hemithorax consistent with recurrent disease. The patient returned home transitioning into hospice care out of state 9 months after diagnosis.
The smears [Figures 2 and 3] and cell block [Figure 4] primarily showed loosely cohesive clusters of pleomorphic spindled and epithelioid cells. The size of the tumor nuclei varied, but the nuclei were often large with irregular nuclear membranes, coarse chromatin and nucleoli. Occasional binucleated and multinucleated cells were observed. The tumor cells had varying amounts of cytoplasm and ill-defined cell borders.
Immunohistochemical studies performed on the cell block showed that the tumor cells were positive for vimentin, focally weak for CD31 and ERG, and nonreactive for pan-keratin, HMB-45, pan melanoma cocktail, smooth muscle actin (SMA), leukocyte common antigen, S-100 protein, and CD34. The tumor was diagnosed as a pleomorphic spindle and epithelioid cell neoplasm, consistent with a sarcoma of the pulmonary artery.
The pulmonary artery resection showed a 5.9 cm x 5.7 cm x 4.1 cm mass involving the right main pulmonary artery and the right upper lobe of the lung [Figure 5]. Histologically, some areas showed atypical spindled cells arranged in a storiform pattern [Figure 6] while other areas contained both pleomorphic spindled and epithelioid cells. Immunohistochemical results revealed that the tumor cells were negative for SMA, desmin, keratin and melanoma cocktail, SOX10, BRAFV600E, CD31, and CD34.
, axial images of chest computed tomography demonstrating a mass (arrow) invading the right pulmonary artery (PA).