A case of leukemic pleural infiltration in atypical chronic myeloid leukemia

Pleural effusion in chronic myeloid leukemia (CML) is poorly understood and rarely reported in the literature. When the pleural effusion is caused by leukemic pleural infiltration, the differential white blood cell count of the effusion is identical to that of the peripheral blood, and the fluid cytology reveals leukemic blasts. We report here a case of bilateral pleural involvement of atypical CML in an 83-yr old male diagnosed with pancreatic cancer with abdominal wall metastasis and incidental peripheral leukocytosis. Based on bone marrow examination, chromosome analysis and polymerase chain reaction he was diagnosed with Philadelphia chromosome negative, BCR/ABL gene rearrangement negative CML. Following 3 months of treatment with gemcitabine for pancreatic cancer, he developed bilateral pleural effusions. All stages of granulocytes and a few blasts were present in both the pleural fluid and a peripheral blood smear. After treatment with hydroxyurea and pleurodesis, the pleural effusion resolved.