CDKN2A and neoplasm: This included a case of a p16‐positive primary tumour with CDKN2A disomy which revealed heterozygous loss in two local recurrences while retaining p16 positivity, and a homozygous deletion with p16 loss in a third local recurrence: this demonstrates a step‐wise acquisition of CDKN2A inactivation in chordoma evolution (case 212).