Cytogenetic abnormalities in multiple myeloma: association with disease characteristics and treatment response

Cytogenetic abnormalities are found in most multiple myeloma (MM) patients. Although their prognostic value has been well studied, there are limited data on the association of primary cytogenetic abnormalities with disease characteristics and treatment response. This study was designed to evaluate these associations. This is a retrospective study including 2027 Mayo Clinic patients diagnosed with MM between February 2004 and February 2018 who had cytogenetic testing by FISH at diagnosis. Translocations t(4;14), t(14;16), t(6;14), and t(14;20) were associated with anemia, beta2microglobulin >5.5 µg/ml and ≥50% bone marrow plasma cells; t(4;14) was associated with higher serum monoclonal protein and plasma cell proliferation. Overall response rate to proteasome inhibitor (PI)-based treatment was higher for IgH translocations compared to trisomies (83% vs. 71%, P = 0.002), but was higher for trisomies with immunomodulatory drug (IMiD)-based treatment (87% vs. 75%, P < 0.001). Time to next treatment was longer with trisomies than IgH translocation with IMiD-based (32.1 vs. 18.4 months, P < 0.001) and PI + IMiD-based (44.0 vs. 27.4 months, P = 0.003) treatments. Outcomes were superior with PI + IMiD combinations in all groups. Our results show that t(4;14), t(14;16), t(6;14), and t(14;20) are associated with high-risk disease characteristics, and IgH translocations and trisomies may be associated with better responses to PIs and IMiDs, respectively.