CDKN2A and acute lymphoblastic leukemia: The dicentric dic(9;20) can be found as a sole chromosomal abnormality or can be masked within complex rearrangements; also, a dicentric dic(9;20) is often associated with mono- or biallelic loss of <i>CDKN2A</i> gene.<h4>Case presentation</h4>Here we report a case of 16-year-old male diagnosed with a de novo pre-B-ALL.