(in Barlogie et al). Multistep molecular pathogenesis of monoclonal gammopathy of undertermined significance (MGUS)/multiple myeloma (MM) tumors.

Defined stages of pathogenesis are depicted, with arrows indicating potential pathways. The approximate timing of several clinical features and oncogenic changes are depicted as thick horizontal lines, with dashed regions reflecting some uncertainty as to the precise time that these changes occur. The vertical line that separates primary and secondary translocations is meant to depict the cessation of IgH switch recombination and somatic hypermutation during B cell maturation.