Blood Res 2017; 52(2):
Published online June 22, 2017
https://doi.org/10.5045/br.2017.52.2.137
© The Korean Society of Hematology
1Department of Pathology, Maulana Azad Medical College, New Delhi, India.
2Department of Biochemistry, Maulana Azad Medical College, New Delhi, India.
Correspondence to : Richa Gupta. Department of Pathology, Maulana Azad Medical College, C 502, Prince Apartments, 54 I. P. Extension, Delhi - 92, India. richagupta0209@gmail.com
Chronic myelogenous leukemia (CML) is a clonal disorder of pluripotent hematopoietic stem cells characterized by a balanced, reciprocal translocation involving chromosomes 9 and 22. Most cases present in the chronic phase (CP) of the disease. The progression from CP to the accelerated phase (AP) or blast crisis (BC) may be seen in patients on maintenance therapy due to the accumulation of various mutations. The most common BC type is myeloid, followed by lymphoid, and rarely megakaryoblastic. We report a case of megakaryoblastic crisis in CML, which is extremely rare and has been documented in very few cases to date.
A 42-year-old man presented with complaints of abdominal distension accompanied by fatigue, weakness, and weight loss for the past three months. His medical history did not include any preexisting hematological or medical disorders. Upon examination, he had mild pallor, and a local abdominal examination revealed massive splenomegaly (6 cm below the costal margin). Complete blood counts showed leukocytosis (White blood cells (WBC), 35×109/L), severe thrombocytosis (platelet count, 10×1011/L), and mild anemia (hemoglobin (Hb), 9.5 g/dL). A peripheral blood smear revealed a normocytic red blood cells along with the presence of immature myeloid precursors (differential count: 5% blasts, 17% promyelocytes, 15% myelocytes, 10% metamyelocytes, 2% basophils, 1% eosinophil, and 50% segmented neutrophils). Based on the above findings, a diagnosis of CML was suggested, which was confirmed by PCR for the
In the absence of therapy, most cases of CML evolve to the blast phase. The most common BC type is myeloid, which is seen in 70% of patients, followed by lymphoid or mixed-lineage phenotype [1]. Megakaryoblastic crisis is rarely encountered in these patients and accounts for less than 3% of cases [2]. To date, although various studies have been performed, no specific mutation has been found that could predict the type of crisis in these patients. As compared to myeloid or lymphoid crisis, megakaryoblastic crisis has a poorer prognosis [3]. Hence, an early detection is imperative for timely administration of chemotherapy with the goal of reverting the disease to chronic phase and proceeding to allogeneic stem cell transplantation (SCT) if possible.
The closest differential of CML in BC is the Philadelphia chromosome (Ph+) AML, as both may share common clinical features and bone marrow morphology. Since their management varies widely, various authors suggest caution in diagnosing CML in BC versus
The exact mechanism of progression to BC is still unknown. Various studies speculate that stem cells undergo additional genetic alterations leading to transformation to BC. In a study done by Calabretta and Perrotti [4], they noted that the ectopic expression of the p210
In conclusion, CML in megakaryocytic BC is rarely encountered in clinical practice. It is important to correctly diagnose these cases as they benefit from a combination of conventional chemotherapy with imatinib, resulting in decreased mortality.
Blood Res 2017; 52(2): 137-139
Published online June 22, 2017 https://doi.org/10.5045/br.2017.52.2.137
Copyright © The Korean Society of Hematology.
Jenna B Bhattacharya1, Richa Gupta1, and Amit Samadhiya2
1Department of Pathology, Maulana Azad Medical College, New Delhi, India.
2Department of Biochemistry, Maulana Azad Medical College, New Delhi, India.
Correspondence to:Richa Gupta. Department of Pathology, Maulana Azad Medical College, C 502, Prince Apartments, 54 I. P. Extension, Delhi - 92, India. richagupta0209@gmail.com
Chronic myelogenous leukemia (CML) is a clonal disorder of pluripotent hematopoietic stem cells characterized by a balanced, reciprocal translocation involving chromosomes 9 and 22. Most cases present in the chronic phase (CP) of the disease. The progression from CP to the accelerated phase (AP) or blast crisis (BC) may be seen in patients on maintenance therapy due to the accumulation of various mutations. The most common BC type is myeloid, followed by lymphoid, and rarely megakaryoblastic. We report a case of megakaryoblastic crisis in CML, which is extremely rare and has been documented in very few cases to date.
A 42-year-old man presented with complaints of abdominal distension accompanied by fatigue, weakness, and weight loss for the past three months. His medical history did not include any preexisting hematological or medical disorders. Upon examination, he had mild pallor, and a local abdominal examination revealed massive splenomegaly (6 cm below the costal margin). Complete blood counts showed leukocytosis (White blood cells (WBC), 35×109/L), severe thrombocytosis (platelet count, 10×1011/L), and mild anemia (hemoglobin (Hb), 9.5 g/dL). A peripheral blood smear revealed a normocytic red blood cells along with the presence of immature myeloid precursors (differential count: 5% blasts, 17% promyelocytes, 15% myelocytes, 10% metamyelocytes, 2% basophils, 1% eosinophil, and 50% segmented neutrophils). Based on the above findings, a diagnosis of CML was suggested, which was confirmed by PCR for the
In the absence of therapy, most cases of CML evolve to the blast phase. The most common BC type is myeloid, which is seen in 70% of patients, followed by lymphoid or mixed-lineage phenotype [1]. Megakaryoblastic crisis is rarely encountered in these patients and accounts for less than 3% of cases [2]. To date, although various studies have been performed, no specific mutation has been found that could predict the type of crisis in these patients. As compared to myeloid or lymphoid crisis, megakaryoblastic crisis has a poorer prognosis [3]. Hence, an early detection is imperative for timely administration of chemotherapy with the goal of reverting the disease to chronic phase and proceeding to allogeneic stem cell transplantation (SCT) if possible.
The closest differential of CML in BC is the Philadelphia chromosome (Ph+) AML, as both may share common clinical features and bone marrow morphology. Since their management varies widely, various authors suggest caution in diagnosing CML in BC versus
The exact mechanism of progression to BC is still unknown. Various studies speculate that stem cells undergo additional genetic alterations leading to transformation to BC. In a study done by Calabretta and Perrotti [4], they noted that the ectopic expression of the p210
In conclusion, CML in megakaryocytic BC is rarely encountered in clinical practice. It is important to correctly diagnose these cases as they benefit from a combination of conventional chemotherapy with imatinib, resulting in decreased mortality.