About 2 % of leukemias affect children under 1 year of age, representing a prevalence of 8-10 cases per million. In more than 2/3 of cases, there is a translocation of the MLL gene on locus 11q23: these forms have a high recurrence rate. Clinically it is mostly ALL but in 1/3 of cases, the clinical picture is that of acute myelocytic leukemia with subcutaneous nodules and cellular infiltrates in all organs. Only a very aggressive chemotherapy is likely to yield some results but the overall prognosis of these leukemias is very poor.

A very particular case is represented by the patients with trisomy 21 who develop in 10 % of cases, a neonatal leukemia or transient neonatal myeloproliliferative syndrome, that cures spontaneously within a few days or weeks. Mutations of the GATA1 gene are often found. The GATA1 gene controls a transcription factor of the megakaryocytic synthesis. These children need to be closely monitored because 20 to 30 % of them will develop typical leukemia, often of the megakaryocytic type, before 3 years of age.

Anesthetic implications:

see acute lymphoblastic leukemias

References :

-        Yoshimi A, Kojima S, Hirano N.
Juvenile myelomonocytic leukemia: epidemiology, etiopathogenesis, diagnosis, and management considerations.
Paediatr Drugs 2010; 12:11-21.

-        Brink DS.
Transient leukemia (transient myeloproliferative disorder, transient abnormal myelopoiesis) of Down syndrome.
Adv Anat Pathol 2006; 13:256-62.

Updated: March 2021