A Case of Rapidly Progressive Granulocyte-colony Stimulating Factor-producing Breast Cancer

Abstract

A 64-year-old woman presented with a rapidly growing mass in the left breast. Breast cancer was diagnosed on the basis of investigations including ultrasound and needle biopsy, and surgery was performed after preoperative chemotherapy. One month postoperatively, computed tomography showed local recurrence and lymph node, lung, and liver metastases. Because the patient had persistent fever and leukocytosis at one point, a liver abscess was suspected, and centesis was performed, but no bacteria were detected, and liver metastasis was diagnosed on the basis of cytology results. Procalcitonin was also low (0.61 ng/ml). Because the leukocytosis was prolonged, a granulocyte-colony stimulating factor (G-CSF)-producing tumor was suspected. Serum G-CSF was elevated at 54 pg/ml, and when surgical specimens were re-stained with anti-G-CSF antibodies, positive cells were observed, leading to a diagnosis of G-CSF-producing breast cancer. Chemotherapy had little effect, and the tumor rapidly metastasized and grew. The patient died five months postoperatively.