[Case report of chemotherapeutic control of a gastric cancer producing granulocyte-colony stimulating factor].

A 79-year-old man presented with a history of vomiting. Laboratory data indicated leukocytosis (26360/μl), and elevated granulocyte-colony stimulating factor (G-CSF) level (155 pg/ml). Upper gastrointestinal endoscopy revealed a type 3 gastric cancer, and subsequent G-CSF immunohistochemical staining of a biopsy specimen was positive. He was therefore diagnosed with a G-CSF-producing gastric cancer. Computed tomography revealed multiple liver metastases. Chemotherapy was initiated, resulting in a partial response for 5 months. G-CSF-producing gastric cancer is rare; thus, we take this opportunity to report our case and to summarize the G-CSF-producing gastric cancer cases reported in Japan.