del 16 in Acute Myeloid Leukaemia (AML) in children: Are the Clinical Implications for Management the Same as for Other Good Risk Cytogenetic Myeloid Leukaemias in Children?

By Marc Hendricks

Recently del 16 has been described in AML in children and adults. According to current guidelines risk stratification for paediatric myeloid leukaemias is based on cytogenetic profiling. Patients with leukaemia with good risk cytogenetic profiles are treated with intensive chemotherapy alone and are not considered candidates for transplantation in first remission. These karyotypes include t(8;21), inv(16), t(16;16) previously described in the association with historical French-American-British M4Eo and t(15;17) in acute promyelocytic leukaemia (APL) along with the other known microvariants.

With the description of the del 16 questions have been raised about whether or not this specific genetic abnormality constitutes a newly discovered good risk variant and whether the same treatment algorithm can be followed as for the other favourable cytogenetic group. The distinction is an important one because it speaks to the need for transplantation to consolidate a remission following intensive chemotherapy: in other words, can transplant be avoided or should children with del16 rather be assigned to a standard risk group and should practitioners then be looking for HLA identical donors to proceed to transplant?

Considering the small number of reported cases there is, as yet, no clear indication that the deletion is interchangeable (as it refers to risk) with inv16 and t(16;16). The source links provided highlight the recent descriptions and the controversial question that it has raised for the management of myeloid leukaemia in children.

Source links: Arthur and Bloomfield (1983),  Rogers et al. (2017), Silva et al. (2004).