Abstract
This paper deals with a case of granulocyte-colony stimulating facor (G-CSF)-producing undifferentiated carcinoma of the rectum in which the disease rapidly progressed to its termination after resection of the primary lesion. A 63-year-old man was admitted to our hospital for thorough examination of a large tumor of the rectum, for which undifferentiated carcinoma was suggested. Because of bleeding from the tumor and no evident metastasizing lesions demonstrated by PET-CT, we performed abdominoperineal rectum resection. However, it became apparent by the 11th postoperative day that the disease had relapsed in the pelvic cavity with multiple metastasizing lesions in the liver and lungs. Also noted were a high-grade fever with marked leukocytosis (>110000/μl) and an elevated serum G-CSF level (115pg/ml) during this period. Afterwards, the patient's condition rapidly deteriorated and he died 26 days after the surgery. Microscopic examination including immunohistochemical staining gave a diagnosis of undifferentiated carcinoma. Furthermore, tumor cells positively stained for anti-G-CSF antibody.
Reports of undifferentiated carcinoma arising in the large bowel are extremely rare and, to the best of our knowledge, no G-CSF-producing undifferentiated carcinoma of the rectum has not been documented to date. Thus, the significance of G-CSF in the clinical course and therapeutic strategies for such patients remain unresolved. Nevertheless, a review of the literature suggests that early detection followed by complete resection of such tumors would be the best possible therapeutic modality at this point.
