Citation: Cruz-Souza JL, Carvalho FPD, Melo MAWD, Leite EP, Marques-Salles TJ. Hemophagocytosis or emperipolesis by lymphoblast after rapid transformation of chronic myeloid leukemia. J Clin Images Med Case Rep. 2021; 2(4): 1219.

Short report

A Male, 11-Years-Old, Admitted In March 2019 With Chronic myelogenous leukemia (CML) in treatment with Imatinib. Three months after diagnosis in outpatient visit was observed increase of splenomegaly and appearing of inguinal and cervical adenomegalies. Bone marrow apiration revealed 70% of blasts, some of them with hemophagocytosis (Figure 1). The immunophenotyping showed blasts positive for CD10, CD19, CD20, CD22, CD79a, CD45, HLA-DR, indicating transformation to B precursors ALL. Bone marrow karyotype was 46,XY,t(9;22), FISH (BCR-ABLES probe) confirmed rearrangement with p210. The patient was treated with higher dose of Imatinib (600 mg/m²), but evolved with bone marrow aplasia and infectious process, being then reajusted to 400 mg/m² with clinical and hematologic improvement. After 30 days had disease aggravation and resistance to Imatinib. The patient initiated EsPh-ALL 2009 protocol, but in D33 with no remission of disease continued with protocol. In September, during consolidation phase evolved with Central Nervous System infiltration and disease persistence, dying for disease in progress. This patient had no clinical findings of Hemophagocytic Lymphohistiocytosis (HLH) and bone marrow cytology showed the several hematopoietic cells inside blast cells.

HLH is a rare disorder of the immune system result of a direct immune activation process familial or due to infectious diseases, autoimmune diseases, malignancies. At least five features can be seen: 1) fever; 2) splenomegaly; 3) cytopenias at least two or three lineages; 4) hypertriglyceridemia and/or hypofibrinogenemia; 5) hemophagocytosis [1-4].

Emperipolesis, which is the presence of an intact cell within the cytoplasm of another cell, is most commonly seen within megakaryocytes, the engulfed cells can be any hematopoietic precursor. It also has been described in malignant cells, including blast cells in the blast phase of CML. Leukemia blasts containing hematopoietic cells have been described in ALL with t(12;21), T-ALL and mainly in megakaryocytic with t(16;21) and t(1;22) or monoblastic with t(8;16), but not always associated with HLH[1-5].

References

1. Andrade FG, Noronha EP, Baseggio RM, Fonseca TCC, Freire BMR, et al. Identification of the MYST3-CREBBP fusion gene in infants with acute myeloid leukemia and hemophagocytosis. Rev Bras Hematol Hemoter. 2016; 38: 291-297.
2. Park JE, Park IJ, Lim YA, Lee WG, Cho SR. Hemophagocytosis by leukemia blasts in B lymphoblastic leukemia with t(12;21) (p13;q22) TEL-AML1 (ETV6-RUNX1): A case report. Ann Clin Lab Sci. 2013; 43: 186-189.
3. Harrison A, Chandra D, Kakkar N, Das S, John MJ. Hemophagocytosis by Leukemic Blasts in T Cell Acute Lymphoblastic Leukemia: An Unusual Finding. Indian J Hematol Blood Transfus. 2016; 32: 23-25.
4. Imashuku S, Hibi S, Kuriyama K, Todo S. Hemophagocytosis by leukemic blasts in a case of acute megakaryoblastic leukemia with t(16;21)(p11;q22). Int J Hematol. 1999; 70: 36–39.
5. Rastogi V, Sharma R, Misra SR, Yadav L, Sharma V. Emperipolesis - A review. J Clin Diagn Res. 2014; 8: ZM01-2.