OS of patients in the TP53-CK class subdivided by those classified as WHO5 MDS with biallelic TP53 inactivation vs other entities and as ICC MDS with mutated TP53 vs other entities. Patients classified as WHO5 MDS with biallelic TP53 inactivation or ICC MDS with mutated TP53 had significantly shorter OS than other patients in the TP53-CK class (P = .0007 and P = .0144, respectively).