The Mutational Profile of Plasma Cell Disorders

Multiple myeloma is a plasma cell malignancy that is the second most common hematologic cancer. The genetics of the disease have been previously characterized by two major subtypes involving recurrent translocations of the immunoglobulin heavy chain, c-MAF, cyclin D (CCND1) and FGFR3/MMSET oncogenes, and the hyperdiploid group with multiple recurrent trisomies. Further, there are characterized cytogenetic/ploidy subsets that appear to carry prognostic significance. Specifically, gains of chromosomes 5, 9, 11, 15, and 19 confer a good prognosis whilst gain of 1q plus deletions of 1p, 12p, 14q, 16q, and 22q confer a poor prognosis. More recently the application of massively parallel sequencing has revealed further insights into the genetic architecture of multiple myeloma. Work from several groups has identified the contribution of mutations in genes involved in non-canonical NF-kB signaling, MAPK signaling and histone methylation, as well as infrequent mutation of cancer genes implicated in other tumor types and novel genes. These data will be presented to give an overall update on the current state of multiple myeloma genetics and our current level of insight in the genomic complexity that characterizes this disease.