Poor Overall Survival in Hyperhaploid Multiple Myeloma Is Defined By Double-Hit Bi-Allelic Inactivation of TP53

Introduction Hyperhaploid multiple myeloma is a rare numerical aberration group defined by a range of 24-34 chromosomes. We have previously shown that hyperhaploid myeloma is associated with a poor prognosis with a 5-year survival rate of 23.1%, compared to 64% for hyperdiploid myeloma, and 80.4% for those with a normal karyotype. It is known that hyperhaploid myeloma frequently has monosomy of chromosome 17, making it a high risk group, but no data are currently available on the mutational status of this interesting sub-group, or how the copy number difference arises.