Juvenile myelomonocytic leukemia with CBL mutation: two cases report and
Juvenile myelomonocytic leukemia (JMML) is an aggressive clonal
hematopoietic disorder of infancy and early childhood. About 15% of
these patients have CBL mutation, which is usually a germline mutation
with a high incidence of CBL syndrome. Conventional chemotherapy would
be little benefit to these children, but epigenetic therapy with the
DNA-hypomethylating agents can make a great difference in disease
control. Here we report two infants diagnosed as JMML with CBL mutation.
One case was treated with 6-mercaptopurine intermittently, but she was
often hospitalized for pneumonia since the disease was not well
controlled. The other one was treated with decitabine. He achieved
clinical complete remission (CR) after three cycles of decitabine
(20mg/m2/d×5 days, repeated every 4 weeks). Unfortunately, the patient’s
symptoms were recurrent two months later. Thus, JMML patient with CBL
mutation has a good clinical response to decitabine, while how and how
long it could be used remain to be further explored.