2019 Volume 33 Issue 2 Pages 161-165
A 45-year-old woman was diagnosed with uterine fibroids 8 years ago. However, she refused medical treatment at that time. Recently, she developed blood in her sputum and visited a nearby hospital. Computed tomography (CT) showed a 60-mm-sized mass in the right upper lung field. The tumor was suspected of being primary lung cancer (cT3N0M0 Stage IIB), and thus, surgery was performed. A sarcoma component was detected on postoperative pathological examination of the lung. Because uterine fibroids were large and were highly suspicious of being lung metastatic tumors, they were resected. The pathological diagnosis was uterine fibroids without malignancy. The lung tumor was further investigated because there was no association between uterine tumors and the lung tumor. Additional immunostaining was performed, and the tumor was diagnosed as a pulmonary blastoma (pT3N0M0 Stage IIB) because it stained positive for β-catenin in both the nucleus and cytoplasm. This report describes a case of pulmonary blastoma, which was difficult to differentiate from metastatic pulmonary tumors, including a large uterine tumor.
