Classification of MDS-del(5q) according to TP53 gene alterations. A total of 129 patients (18.9%) were categorized as TP53-mut, whereas 553 (81.1%) were designated as TP53-wt. Upon the integration of all molecular data, TP53-mut patients were further categorized into TP53 monoallelic in 76% of cases (n = 98), 14.4% of the entire cohort, and TP53 multihit in 24% (n = 31), 4.5% of the entire cohort. Among TP53-monoallelic patients, 46 (46.9%) had a single TP53 mutation with a VAF of <50%, without deletion or cnLOH. In the remaining 53.1% (n = 52) data of deletions and/or cnLOH were unavailable. Among TP53-multihit patients, 51.6% (n = 16) presented multiple mutations (15 patients had 2 mutations, and 1 had 3 mutations); 41.9% (n = 13) showed 1 mutation with VAF >50%, and 6.5% (n = 2) showed 1 TP53 mutation plus cnLOH.