Chronic myeloid leukemia after chemotherapy for adenocarcinoma of the rectum: A case report

Abstract

Chronic myeloid leukemia (CML) after chemotherapy for any primary malignancy has been occasionally reported. Herein we reported one definite case of CML who was diagnosed after the treatment of adenocarcinoma of the rectum. A 79-year-old Thai man was diagnosed with moderately differentiated adenocarcinoma of the rectum invading the urinary bladder. And he was treated with rectal resection and lymph nodes excision, followed by 5-fluoro-uracil and leucovorin therapy. He remained in complete remission for 1.5 years until he suddenly passed
the hematochezia for one day and very high white blood cell and platelet counts without weight loss. The physical examination revealed no hepatosplenomegaly, no abdominal mass. The blood tests revealed: hemoglobin 10.6 g%, white blood cell 57,100/mm3, platelet 2,898,000/ mm3, neutrophil 68 %, lymphocyte 6 %, basophil 20 %, band 1 %. The chromosome study from the blood was positive for 46,XY,t(9;22) (q34;q11.2)[20] but negative for JAK-2 V617F mutation. Serum Carcinoembryonic antigen (CEA) level was continually normal both before the surgery and through out the follow-up. His definite diagnosis was established as CML, the accelerated phase with the history of 5-FU chemotherapy for the adenocarcinoma of the rectum. He did not accept further investigations for detecting the local recurrence of the rectal adenocarcinoma and refused tyrosine kinase inhibitor therapy. He could survive one year after the diagnosis of CML without serious symptom while this study was being reported. So far it could not be concluded that the occurrence of CML after the chemotherapy of the rectum adenocarcinoma isjust co-incidental or has any relationship.