A rare case of systemic mastocytosis with t(8;21) acute myeloid leukaemia in a young girl: a case report

Abstract

Mastocytosis is a rare disorder due to the abnormal proliferation  of  clonal  mast  cells.  Mast  cells  exist in  most  tissues,  mature  in  situ  from  hematopoietic stem cells and develop unique characteristics of local effector  cells.  It  manifests  as  two  main  categories: cutaneous mastocytosis and systemic mastocytosis (SM).    Patients  presenting  with  SM–acute  myeloid leukaemia (AML) often have the worst outcome.  Here we present a patient with the simultaneous diagnosis of SM  associated  with  t  (8;21)  (q22;q22)  acute  myeloid leukaemia, M2 subtype in the French-American-British (FAB) classification, carrying a population of immature mast  cell  precursors.    Initially,  she  was  diagnosed with AML with t (8;21) (q22;q22)  and was started on induction  chemotherapy.  Subsequent  trephine  biopsy evaluation  post-induction  chemotherapy  showed  no increase  in  blast  cells.  However,  abnormal  mast  cells were  seen  distributed  throughout  the  marrow  spaces, which expressed mast cell tryptase, CD117 and CD68. She was then diagnosed as SM associated with t(8;21) (q22;q22)  AML.  Unfortunately,  she  succumbed to  death  due  to  severe  neutropenic  sepsis  post- induction  chemotherapy.  By  sharing  the  knowledge, hopefully  it  will  help  the  clinicians  as  the  diagnosis of  SM  is  difficult  to  establish  because  the  associated malignancy  may  obscure  the  morphological  features of SM. However, a reduction in blast cell percentage at the time  of  a  post-induction marrow  evaluation helps in diagnosis.

Bangladesh Journal of Medical Science Vol. 23 No. 03 July’24 Page : 873-876