RHAMM isoform balance in BM samples is prognostic in multiple myeloma. Kaplan-Meier survival curves for myeloma patients with RHAMM ratios of less than 0.8 (red), 0.8 to 1.2 (green), and more than 1.2 (blue) in the bone marrow at diagnosis. Survival is increasingly poor with increasing RHAMM ratio (P = .003 by the log-rank test). RHAMM ratios were determined using RT-PCR and capillary fragment analysis.