CDKN2A and neuroblastoma: Our results also suggest that CDKN2A gene deletions are rare events in NB tumours, in agreement with several prior studies in NB (Beltinger et al, 1995; Diccianni et al, 1996; Kawamata et al, 1996; Castresana et al, 1997; Iolascon et al, 1998).