Timeline analysis of RHAMM^-exon4/RHAMM^FL ratios within t(4;14)⁺ MM patient blood samples. PBMC samples were acquired and archived between 1998 and 2002 as described previously.⁶  Detection of t(4;14) fusion transcript used 2 RT-PCR reactions targeting first JH/MMSET and then Iμ/MMSET.⁶  Samples are classified as MMSET negative (-), MMSET positive for both reactions (+), or MMSET positive for one reaction (±). Samples are also classified as containing clonotypic CDR2/3 message (+) or lacking clonotypic CDR2/3 message (-). Only samples that were MMSET positive in at least one reaction are shown along with the immediately neighboring MMSET-negative samples. Polynomial trendlines for RHAMM^-exon4/RHAMM^FL ratios (Microsoft Excel) are indicated for samples with detectable t(4;14) message. Serum M protein levels at the time of each PBMC sample are also indicated. Arrows indicate time of transplantation and disease relapse.