[Granulocyte-colony stimulating factor producing tumor with high serum interleukin-6].

A 53-year-old man admitted to our hospital because of fever and chest abnormal shadow. Chest X-ray and computed tomography (CT) scan revealed large tumor on right upper lobe. Serum interleukin (IL)-6 and granulocyte-colony stimulating factor (G-CSF) were high. Right upper lobectomy and chest wall resection was performed. Histological diagnosis was large cell carcinoma. Immunohistological examination of lung tumor cells showed positive staining for G-CSF in only 1% of them. We diagnosed that tumor was G-CSF producing tumor and we thought that tumor produced IL-6.