Abstract
We examined a 39-year-old male who had lost consciousness, and a mediastinal tumor was incidentally detected. He had a fever and increased leukocyte/CRP levels but did not respond to antibiotics, and neoplastic fever was suspected. Chest CT scanning showed a mass lesion in the upper mediastinum. Mediastinoscopic biopsy suggested squamous cell carcinoma. Although complete resection was attempted after medial sternotomy, resection was impossible due to extensive infiltration. Postoperative histological examination demonstrated thymic carcinoma (lymphoepithelioma-like carcinoma). The postoperative serum G-CSF level was high (276 pg/ml). Immunostaining for G-CSF was positive, confirming it to be a G-CSF-producing tumor. After the operation, he underwent a course of chemotherapy in our hospital, and was then transferred to another hospital for radiotherapy.
