Haymann, Suzanne

Introduction: Abnormal metaphase cytogenetics are associated with inferior survival in newly diagnosed multiple myeloma (MM). These abnormalities are only detected in one third of cases due to the low proliferative rate of plasma cells. It is unknown if metaphase cytogenetics improve risk stratification when using contemporary prognostic models such as the revised international staging system (R-ISS), which incorporates interphase fluorescence in situ hybridization (FISH). Aims: The aims of this study were to 1) characterize the association between abnormalities on metaphase cytogenetics and overall survival (OS) in newly diagnosed MM treated with novel agents and 2) evaluate whether the addition of metaphase cytogenetics to R-ISS, age, and plasma cell labeling index (PCLI) improves model discrimination with respect to OS. Methods: We analyzed a retrospective cohort of 483 newly diagnosed MM patients treated with proteasome inhibitors (PI) and/or immunomodulators (IMID) who had metaphase cytogenetics performed prior to initiation of therapy. Abnormal metaphase cytogenetics were defined as MM specific abnormalities, while normal metaphase cytogenetics included constitutional cytogenetic variants, age-related Y chromosome loss, and normal metaphase karyotypes. Multivariable adjusted proportional hazards regression models were fit for the association between known prognostic factors and OS. Covariates associated with inferior OS on multivariable analysis included R-ISS stage, age ≥ 70, PCLI ≥ 2, and abnormal metaphase cytogenetics. We devised a risk scoring system weighted by their respective hazard ratios (R-ISS II +1, R-ISS III + 2, age ≥ 70 +2, PCLI ≥ 2 +1, metaphase cytogenetic abnormalities + 1). Low (LR), intermediate (IR), and high risk (HR) groups were established based on risk scores of 0-1, 2-3, and 4-5 in modeling without metaphase cytogenetics, and scores of 0-1, 2-3, and 4-6 in modeling incorporating metaphase cytogenetics, respectively. Survival estimates were calculated using the Kaplan-Meier method. Survival analysis was stratified by LR, IR, and HR groups in models 1) excluding metaphase cytogenetics 2) including metaphase cytogenetics and 3) including metaphase cytogenetics, with IR stratified by presence and absence of metaphase cytogenetic abnormalities. Survival estimates were compared between groups using the log-rank test. Harrell's C was used to compare the predictive power of risk modeling with and without metaphase cytogenetics. Results: Median age at diagnosis was 66 (31-95), 281 patients (58%) were men, median follow up was 5.5 years (0.04-14.4), and median OS was 6.4 years (95% CI 5.7-6.8). Ninety-seven patients (20%) were R-ISS stage I, 318 (66%) stage II, and 68 (14%) stage III. One-hundred and fourteen patients (24%) had high-risk abnormalities by FISH, and 115 (24%) had abnormal metaphase cytogenetics. Three-hundred and thirteen patients (65%) received an IMID, 119 (25%) a PI, 51 (10%) received IMID and PI, and 137 (28%) underwent upfront autologous hematopoietic stem cell transplantation (ASCT). On multivariable analysis, R-ISS (HR 1.59, 95% CI 1.29-1.97, p < 0.001), age ≥ 70 (HR 2.32, 95% CI 1.83-2.93, p < 0.001), PCLI ≥ 2, (HR 1.52, 95% CI 1.16-2.00, p=0.002) and abnormalities on metaphase cytogenetics (HR 1.35, 95% CI 1.05-1.75, p=0.019) were associated with inferior OS. IR and HR groups experienced significantly worse survival compared to LR groups in models excluding (Figure 1A) and including (Figure 1B) the effect of metaphase cytogenetics (p < 0.001 for all comparisons). However, the inclusion of metaphase cytogenetics did not improve discrimination. Likewise, subgroup analysis of IR patients by the presence or absence of metaphase cytogenetic abnormalities did not improve risk stratification (Figure 1C) (p < 0.001). The addition of metaphase cytogenetics to risk modeling with R-ISS stage, age ≥ 70, and PCLI ≥ 2 did not improve prognostic performance when evaluated by Harrell's C (c=0.636 without cytogenetics, c=0.642 with cytogenetics, absolute difference 0.005, 95% CI 0.002-0.012, p=0.142). Conclusions: Abnormalities on metaphase cytogenetics at diagnosis are associated with inferior OS in MM when accounting for the effects of R-ISS, age, and PCLI. However, the addition of metaphase cytogenetics to prognostic modeling incorporating these covariates did not significantly improve risk stratification. Disclosures Lacy: Celgene: Research Funding. Dispenzieri:Akcea: Consultancy; Intellia: Consultancy; Alnylam: Research Funding; Celgene: Research Funding; Janssen: Consultancy; Pfizer: Research Funding; Takeda: Research Funding. Kapoor:Celgene: Honoraria; Sanofi: Consultancy, Research Funding; Janssen: Research Funding; Cellectar: Consultancy; Takeda: Honoraria, Research Funding; Amgen: Research Funding; Glaxo Smith Kline: Research Funding. Leung:Prothena: Membership on an entity's Board of Directors or advisory committees; Takeda: Research Funding; Omeros: Research Funding; Aduro: Membership on an entity's Board of Directors or advisory committees. Kumar:Celgene: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Takeda: Research Funding.

Abstract Background The survival of patients with multiple myeloma (MM) has improved significantly over the past two decades with the introduction of novel treatment agents. However, MM is still largely considered an incurable malignancy with a relapsing-remitting course. A follow-up of at least 10 years from active disease is required to determine whether a plateau in progression-free survival has been attained. Prior literature has used 10 years as a cutoff for "long-term survivorship". In this study, we have assessed the biological disease characteristics and outcomes of long-term survivors with MM (≥10 years from active disease). Methods All patients with active MM evaluated at the Mayo Clinic, Rochester between January 1, 1999 and July 1, 2008 were included in the study after approval of the Institutional Review Board. Patients with smoldering multiple myeloma were excluded. The overall survival (OS) was calculated from the time of symptomatic disease requiring treatment. Patients were then divided into two cohorts: (1) long-term survivors, which included patients who had an overall survival of at least 10 years; and (2) short-term survivors, which included patients who had an overall survival of less than 5 years from the diagnosis of active MM. The baseline characteristics between these two groups were compared using Wilcoxon, chi-square, and Fisher's exact test as applicable. All time-to-event analyses were performed using the Kaplan-Meier method and the survival curves were compared using Log-Rank test. Results During the time frame of the study, 2,125 patients were identified who fulfilled the diagnostic criteria for active MM. The median follow-up for the entire cohort was 12.6 years (95% CI: 12.5-13.4).The median OS for the entire cohort was 4.4 years (95% CI: 4.2-4.7 years). Three-hundred and ninety nine (18.7%) patients survived at least 10 years whereas 872 patients (41%) survived less than 5 years from the date of initial diagnosis. The median OS was 14.1 years for the long-term survivors (95% CI: 13.9-14.6 years) and 2.1 years for the short-term survivors (95% CI: 1.8-2.2 years). The clinical features at diagnosis comparing long-term survivors and short-term survivors are shown in Table 1. Among long-term survivors (n=399), based on the available data regarding remission and ongoing treatment status, 331 patients were categorized into 6 cohorts (Table 2). The MM specific survival data of these 6 cohorts is depicted in Table 2.Figure 1 shows survival outcomes from the 10-year landmark. Of the 6 cohorts, 38 patients in Cohort 1 and 19 patients in Cohort 2 (total 57; 17% of long term survivors, ~3% of the entire cohort ) have been off therapy for at least 5 years and remain in remission, representing a distinct group of patients with 100% 15-year survival. Conclusion In our large database with prolonged follow-up, long-term survivors appear to have distinct baseline characteristics, but also constitute a heterogenous group of patients with disparate outcomes. A small subset (17% of long-term survivors) was identified that may represent patients closest to being considered as 'operationally cured'. Disclosures Lacy: Celgene: Research Funding. Dispenzieri:Celgene, Takeda, Prothena, Jannsen, Pfizer, Alnylam, GSK: Research Funding. Gertz:Teva: Consultancy; spectrum: Consultancy, Honoraria; Medscape: Consultancy; Physicians Education Resource: Consultancy; Amgen: Consultancy; Apellis: Consultancy; Alnylam: Honoraria; Abbvie: Consultancy; janssen: Consultancy; celgene: Consultancy; Prothena: Honoraria; annexon: Consultancy; Ionis: Honoraria; Research to Practice: Consultancy. Dingli:Alexion Pharmaceuticals, Inc.: Other: Participates in the International PNH Registry (for Mayo Clinic, Rochester) for Alexion Pharmaceuticals, Inc.; Millennium Takeda: Research Funding; Alexion Pharmaceuticals, Inc.: Other: Participates in the International PNH Registry (for Mayo Clinic, Rochester) for Alexion Pharmaceuticals, Inc.; Millennium Takeda: Research Funding. Kumar:KITE: Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Merck: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Research Funding; KITE: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees; AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding. Kapoor:Celgene: Research Funding; Takeda: Research Funding.