A Case of Myeloid Sarcoma Presenting as a Large Pleural Effusion -the Diagnostic Utility of Medical Thoracoscopy-

Abstract

Background. Myeloid sarcoma, which is defined as an extramedullary tumor-forming neoplasm that consists of immature myeloid cells, is a rare disease. Some reports have described patients with mediastinal myeloid sarcoma with a malignant pleural effusion. We herein describe the case of a patient with mediastinal myeloid sarcoma presenting with pleural dissemination. Case. A 26-year-old man presented with cough and exertional dyspnea. Chest CT on admission revealed a massive left pleural effusion and an anterior mediastinal mass. We performed medical thoracoscopy in order to obtain a diagnosis and perform pleural drainage. Thoracoscopy revealed a large number of small nodules that were diffusely distributed on the parietal pleura. He was diagnosed with myeloid sarcoma based on the results of a cytological examination of the pleural effusion and a pleural biopsy. Conclusion. To the best of our knowledge, this is the first report to describe the pleural lesions of myeloid sarcoma that were identified by thoracoscopy. Medical thoracoscopy was useful in the diagnosis of the present patient.