PF564 OUTCOMES OF PATIENTS WITH T(11;14) MULTIPLE MYELOMA: AN INTERNATIONAL MYELOMA WORKING GROUP MULTICENTER STUDY

Background: Multiple myeloma (MM) is a heterogeneous disease with varying survival outcomes depending on the presence of certain genetic abnormalities. Common abnormalities include trisomies, translocations involving the chromosome 14, and amplifications or deletions of chromosomes 1, 13, and 17. t(11;14), occurring in 15% of patients with myeloma, had been considered a standard risk abnormality, but recent data suggest inferior outcome. This is important as new therapeutic options such as the BCL‐2 inhibitor venetoclax has been shown to be particularly effective in t(11;14) patients. Aims: Primary objective: To describe the overall survival of myeloma patients with translocation t(11:14) Secondary objectives: To determine the response rates, progression free survival, time to progression, time to next treatment, duration of responses and overall survival with different regimens among patients with t(11;14), to determine the prognostic factors for overall survival among patients with t(11;14), and to identify the spectrum of co‐existing genetic abnormalities among patients with t(11;14) Methods: This was a multicenter study to identify the outcomes of patients with t(11;14), using a retrospectively assembled cohort. Patients with MM diagnosed between 2005 and 2015 with t(11;14) identified on FISH performed within six months of diagnosis, and with treatment details available and if alive, a minimum of 12 months of follow up, were enrolled. Results: The current analysis includes 848 patients; median age of 64.4 years; 60.0% male. The median follow‐up from diagnosis for the entire cohort was 46.5 months; 86.7% of the patients were alive at the last follow up. ISS stage distribution included: Stage I (35.3%), Stage II (38.9%) and Stage III (25.8%). The distribution of FISH abnormalities included: del 13q (14.5%), 1q amp (12.1%), del 17p or monosomy 17 (6.1%). Initial therapy included different regimens: 23.3% had an IMiD, 43.3% had a PI, 20.0% had both and 13.3% had no novel agent. The drug classes by line of therapy are shown in Table 1. A stem cell transplant (SCT), defined as within 12 months of start of first line treatment, was used in 39.1% of patients. The median time to next treatment (TTNT) after initial treatment was 13.7 (95% CI: 11.3 to 16.5) months. The median overall survival (OS) from diagnosis for the entire cohort was 82.5 (95% CI: 73.5 to 95.8) months; 4‐year estimates for those diagnosed from January 2005 to December 2009, and from January 2010 to December 2014 were 75.1% and 70.2%, respectively. Median OS by initial regimen is shown in Figure 1; those receiving an early SCT had median OS of 116.9 (95% CI: 85.6 to NA) months. Summary/Conclusion: This is the first study to examine the outcomes of a large group of myeloma patients with t(11;14) abnormality. Patients receiving a combination of a PI and an IMiD appear to have the best survival outcomes. Patients receiving an early SCT appear to have excellent survival with median OS approaching 10 years. Additional patients are being accrued to this study and additional analysis examining the variables affecting response duration and survival will be presented.