Sclerosing Pneumocytoma of Lung Mimic Metastatic Carcinoma

A 60-year-old married woman presented with a history of general weakness, limb weakness, and vaginal bleeding for 1 month. After admission to our emergency department, she underwent dilation and curettage of endometrial tissue, and the pathology report was endometrioid carcinoma, grade 3. Computer tomography of the chest revealed one round nodule measuring 1.6 cm in size in the left lower lung lobe, and it was suspicious for metastatic endometrioid carcinoma. The patient underwent staging surgery for the uterine tumor. The pathological stage of endometrioid carcinoma was IB (T1b, N0, Mx). Three weeks later, the patient underwent computer tomography-guided biopsy of the lung tumor, and the pathological diagnosis was sclerosing pneumocytoma. She was followed up in our outpatient department after surgery for endometrioid carcinoma and biopsy of lung tumor. No enlargement of the sclerosing pneumocytoma lesion and no recurrent lesion of endometrioid carcinoma were noted after 5 years of follow-up. Sclerosing pneumocytoma typically presents as a unilateral pulmonary nodule, and this tumor typically behaves in a benign manner. In endometrioid carcinoma, the simultaneous appearance of sclerosing pneumocytoma may mimic a metastatic lung lesion.