Unusual presentation of extramedullary blast crisis in chronic myeloid leukemia: A case report

Abstract

BACKGROUND Extramedullary blast crisis in chronic myeloid leukemia (CML) is an uncommon occurrence of leukemic blast infiltration in regions other than the bone marrow. Malignant infiltration of the serosal membranes should be considered in cases where CML presents with ascites or pleural effusion. CASE SUMMARY A 23-year-old female with CML presented with progressively worsening ascites and pleural effusion despite first-line tyrosine kinase inhibitor treatment. Her blood work indicated leukocytosis with myelocyte bulge and 2% blasts. Analysis of the patient’s bone marrow confirmed the chronic phase of CML. Abdominal ultrasound revealed hepatosplenomegaly with ascites. The fluid investigation of both ascites and pleural effusion revealed a predominance of neutrophils with exudate. However, no acid-fast bacilli or growth was observed after culturing. Although hydroxyurea reduced cell counts, there was no observed effect on ascites or pleural effusion. Repeat investigation of the ascitic and pleural fluid revealed a polymorphous myeloid cell population consisting of myelocytes, metamyelocytes, band forms, neutrophils and a few myeloblasts. Extramedullary blast crisis was suspected, and mutation analysis was performed. We switched the patient to dasatinib. The patient’s symptoms were relieved, and ascites and pleural effusion diminished. CONCLUSION Serosal membrane involvement in CML is extremely rare. In this case, the patient responded well to dasatinib treatment.