Granulocyte-colony stimulating factor-producing squamous cell carcinoma arising in ovarian mature cystic teratoma: A case report

Granulocyte-colony stimulating factor (G-CSF)-producing cancer has been reported to occur in various organs. It has an aggressive nature and shows resistance to conventional treatments, however, its clinical features are not well known because of the small number or reported cases. We report G-CSF-producing squamous cell carcinoma arising in malignant-transformed ovarian mature cystic teratoma. An 80-year-old woman underwent suboptimal surgical excision of stage IIIC ovarian cancer. Prior to the treatment, the patient presented severe granulocytosis and elevated serum G-CSF concentration. With the help of histopathological and immunohistochemical studies, we diagnosed this case to be a poorly differentiated squamous cell carcinoma developed in ovarian mature cystic teratoma, which highly expressed G-CSF. During radiation therapy, the patient died from rapid growth of residual tumor and peritoneal dissemination 2 months after surgery. This is the first case of G-CSF-producing squamous cell carcinoma arising in malignant-transformed ovarian mature cystic teratoma, and its prognosis was very poor.