Cytogenetic Features and Clinical Outcomes of Patients With Non-secretory Multiple Myeloma in the Era of Novel Agent Induction Therapy

BACKGROUND

Non-secretory multiple myeloma (NSMM) is a rare subtype of multiple myeloma (MM) characterized by the absence of monoclonal protein in the serum and/or urine. We look at the clinical and cytogenetic features of NSMM in this study.

PATIENTS AND METHODS

This study evaluates a cohort of 30 patients with newly diagnosed NSMM seen at the Mayo Clinic, Rochester, MN, between 2008 and 2018 and treated with novel agent induction therapies. Survival outcomes were estimated using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

These patients with NSMM appear to have a large disease burden at diagnosis with a median bone marrow plasma cell percentage of 70% and more than one-half of all patients having Multiple Myeloma International Staging System Stage III disease. There was a higher preponderance for t(11;14) primary cytogenetic abnormality in this NSMM cohort, accounting for more than 50% of the cohort. Finally, the overall survival of this cohort appears to be slightly worse than a matched-control group of newly diagnosed patients with MM with secretory disease.

CONCLUSIONS

Future multi-institution studies confirming these above findings on this rare entity are warranted.

Impact of consolidation therapy post autologous stem cell transplant in patients with light chain amyloidosis

The role of consolidation post autologous stem cell transplant in light chain amyloidosis is not well defined. We retrospectively identified patients who had light chain amyloidosis and underwent autologous stem cell transplant at the Mayo Clinic. Consolidation was defined as any treatment given after the day 100 evaluation post-transplant to maintain or deepen the response. We identified 471 patients, of whom 72 (15%) received consolidation. Patients receiving consolidation had more advanced disease (Mayo 2012 stage ≥II in 67% vs 52%, P = .02), and had lower day 100 response rates (very good partial response or better: 35% vs 84%, P < .001). After consolidation, rates of very good partial response improved from 24% to 28%, and rates of complete response improved from 11% to 40%. Patients with less than very good partial response who received consolidation, had better progression-free survival (median of 22.4 vs 8.8 months, P < .001), and the benefit was greater in those who deepened their response (median of 41 vs 8.8 months, P < .001). In patients with less than very good partial response, there was a trend for better overall survival in patients who responded to consolidation (median of 125.8 vs 74.4 months, P = .07). In patients who achieved very good partial response, or better, at day 100 post autologous stem cell transplant, consolidation did not improve progression-free or overall survival. Consolidation after autologous stem cell transplant for light chain amyloidosis improves progression-free survival for patients who achieve less than very good partial response.

Fifteen year overall survival rates after autologous stem cell transplantation for AL amyloidosis

In appropriately selected patients with AL amyloidosis, autologous stem cell transplant (ASCT) is an established treatment modality with excellent outcomes and decreasing transplant related mortality (TRM) over time. We report on 15-year overall survival (OS) in 159 patients undergoing ASCT from 1996 to 2003, with median follow up of 17.1 years. Day 100 TRM was 13.2% (n = 21). The OS of ≥15 years was observed in 30% (47/159) of patients. Patients surviving ≥15 years were younger (53 vs 56 years, P = .02), less likely to have lambda as the involved light chain (62% vs 78%, P = .03) and were less likely to have heart involvement (32% vs 56%, P = .005). Median OS of patients with heart involvement vs not was 4.0 vs 11.1 years, P = .006 and actuarial 15-year OS was 23% vs 43%, respectively. A higher proportion of patients with OS ≥15 years received full-dose melphalan conditioning (81% vs 61%, P = .01), and achieved day 100 complete response (CR) (64% vs 24%, P < .001). Median OS amongst patients who achieved CR vs not was 19.3 vs 5.4 years, P < .001. Heart involvement, receiving full-dose melphalan and achieving CR remained independent predictors of OS. AL amyloidosis and related complications were the cause of death in 52% of patients overall (1-5 years post-transplant: 81%; 5-10 years: 62% and 10-15 years: 55%). These results reinforce the key role of ASCT in AL amyloidosis. With improvements in TRM and more options for relapsed disease, we expect the long-term survival post-transplant to improve significantly in the future.

Independent Prognostic Value of Stroke Volume Index in Patients With Immunoglobulin Light Chain Amyloidosis

BACKGROUND

Heart involvement is the most important prognostic determinant in AL amyloidosis patients. Echocardiography is a cornerstone for the diagnosis and provides important prognostic information.

METHODS AND RESULTS

We studied 754 patients with AL amyloidosis who underwent echocardiographic assessment at the Mayo Clinic, including a Doppler-derived measurement of stroke volume (SV) within 30 days of their diagnosis to explore the prognostic role of echocardiographic variables in the context of a well-established soluble cardiac biomarker staging system. Reproducibility of SV, myocardial contraction fraction, and left ventricular strain was assessed in a separate, yet comparable, study cohort of 150 patients from the Pavia Amyloidosis Center. The echocardiographic measures most predictive for overall survival were SV index <33 mL/min, myocardial contraction fraction <34%, and cardiac index <2.4 L/min/m² with respective hazard ratios (95% confidence intervals) of 2.95 (2.37-3.66), 2.36 (1.96-2.85), and 2.32 (1.91-2.80). For the subset that had left ventricular strain performed, the prognostic cut point was -14% (hazard ratios, 2.70; 95% confidence intervals, 1.84-3.96). Each parameter was independent of systolic blood pressure, Mayo staging system (NT-proBNP [N-terminal pro-B-type natriuretic peptide] and troponin), and ejection fraction on multivariable analysis. Simple predictive models for survival, including biomarker staging along with SV index or left ventricular strain, were generated.

CONCLUSIONS

SV index prognostic performance was similar to left ventricular strain in predicting survival in AL amyloidosis, independently of biomarker staging. Because SV index is routinely calculated and widely available, it could serve as the preferred echocardiographic measure to predict outcomes in AL amyloidosis patients.

Ten-year survivors in AL amyloidosis: characteristics and treatment pattern

Improvement in survival in Light chain (AL) amyloidosis has been seen over recent decades, enabling more patients to achieve long-term survival. Patients with AL amyloidosis who survived ≥10 years from time of diagnosis (n = 186) were the subject of this study. Ten-year survivors represented 22% of the total population. These patients were characterized by favourable patient, organ and plasma cell features. Of note, trisomies were less common among 10-year survivors compared to those who did not survive to 10 years. All-time best haematological response was complete response in 67%, very good partial response in 30%, partial response in 2% and no response in 1%, with 11% having received a consolidative strategy for inadequate response to first line therapy. The overall organ response rate to first-line therapy was 76%, which increased to 86% when considering subsequent line(s) of therapy. Forty-seven percent of the 10-year survivors did not require a second-line therapy. The median treatment-free survival (TFS) among the 10-year survivors was 10·5 years (interquartile range 7·4-12·2). On multivariate analysis independent predictors for TFS were the achievement of complete haematological response and lack of cardiac involvement. Long-term survivors are increasingly seen in AL amyloidosis and present distinct patient, organ and clonal disease features.

Prognostic value of minimal residual disease and polyclonal plasma cells in myeloma patients achieving a complete response to therapy

Achievement of a complete response has been associated with improved outcomes in patients with multiple myeloma. Recently, increasing application of minimal residual disease (MRD) assessment has shown that MRD negativity is a powerful prognostic factor for survival outcomes. We wanted to examine the impact of the polyclonal plasma cell (pPC) compartment among patients in complete response (CR) but are MRD positive. This is a retrospective cohort study where 460 myeloma patients were identified who met criteria for CR and had multicolor flow cytometry performed on the bone marrow (BM). Monoclonal and pPCs were estimated during MRD testing. Final outcomes including overall survival (OS) and time to next treatment (TTNT) were compared among the groups. The median OS for the entire cohort was not reached (95% CI; 63 mos, NR) and the median TTNT was 31 months (95% CI; 27,36). Among the MRD_neg group, median TTNT was 37.6 months vs 23 months for MRD_pos patients (P < .001); the median OS was not reached for either group, but there was a trend toward better survival for MRD_neg patients. Among the MRD_pos group, median percentage of pPCs was 65% (2.5-98.5), and those with >95% pPCs had a significantly better TTNT (NR vs 23 months; P = .02) and a trend toward better OS. We conclude that achievement of MRD negativity predicts for better response durability and trend toward improved OS and an increased proportion of pPC predicts for better outcomes within those who have residual tumor cells highlighting the importance of marrow normalization.

The impact of re-induction prior to salvage autologous stem cell transplantation in multiple myeloma

Autologous stem cell transplantation (ASCT) is an integral component of the therapeutic arsenal in multiple myeloma. Given that overall survival (OS) is comparable between patients receiving up-front or delayed ASCT, some opt to collect stem cells and postpone transplant until the time of disease progression (i.e. salvage ASCT). It is unknown if induction should be repeated prior to salvage ASCT, or if patients should proceed directly. We identified 234 patients who underwent salvage ASCT at our institution: 188 (80%) were re-induced, whereas 46 (20%) proceeded directly without re-induction. There was no significant difference in time to next therapy (TNT) or OS from Day 0 between the two groups. Patients who were re-induced had a nonsignificant trend towards a higher rate of complete response post-ASCT (45% vs. 33%, p= .12). In multivariate models, re-induction did not affect TNT/OS. In the subgroup of 188 patients who were re-induced, patients with relapsed/refractory disease at the time of ASCT had significantly shorter TNT/OS compared to patients with deeper pre-ASCT responses. In summary, there was no survival difference for patients who were re-induced before salvage ASCT. However, many factors affect the decision to re-induce, and prospective studies would be required to discern its role definitively.

Ixazomib, lenalidomide, and dexamethasone for patients with POEMS syndrome

8019

Background: POEMS syndrome is a rare paraneoplastic syndrome caused by an underlying plasma cell disorder. Most of the information regarding treatment has been gleaned from retrospective data. The combination of a proteasome inhibitor, an IMiD and corticosteroid is known to be highly effective among patients with myeloma. Methods: We designed a pilot using a 28-day oral regimen of ixazomib (4 mg days 1, 8, 15), lenalidomide (25 mg days 1-21), and dexamethasone (20 mg days 1, 8, 15, 22). Aspirin and acyclovir were used for prophylaxis. Eligibility included a diagnosis of POEMS syndrome, a plasma VEGF > 200 pg/ml, a PS < 3. There were two groups [gp] (intended enrollment 15 per gp): Gp A, 13 cycles for patients (pts) who had relapsed or refractory disease; Gp B, 3 cycles for pts destined for high-dose chemotherapy with stem cell transplant. Primary endpoint was VEGF complete response (CR = normalization) after 3 cycles. Secondary endpoints included safety, hematologic response, and overall survival at 3 and 12 months. Other domains including PET response, clinical responses including neurologic response were also studied. To date, 13 pts enrolled since 10/31/2016—4 to Gp A and 9 to Gp B. 11 pts were analyzed (2 dropped out before receiving any therapy). Data were frozen as of 1/21/2019. Results: Median age was 55; 73% were male. So far, overall 64% met primary endpoint of VEGF CR (Table). The median follow-up of survivors is 12.4 mo (6, 24). 1 pt came off study for non-responsive disease and died thereafter. 38% of patients had grade 3+hematologic AE; 72% had grade 3-4 non-hematologic AE. These included: rash, respiratory infection and hypotension in 2 each; atrial fibrillation, diarrhea, edema, dyspnea, and thromboembolism in 1 each. 4 pts had non-objective worsening of their neuropathy. Conclusions: These preliminary results suggest that Ixa-Len-Dex is an effective and tolerable regimen for patients with POEMS syndrome. Clinical trial information: NCT02921893. [Table: see text]

Upstaging the R-ISS classification of newly diagnosed multiple myeloma (NDMM) patients (pts) by quantifying circulating clonal plasma cells (cPCs) via multiparametric flow cytometry (MFC)

8031

Background: Our prior studies identified the prognostic significance of ≥400 cPCs/150,000 analyzed events quantified by MFC in NDMM. We evaluated if a similar quantification of cPCs using MFC can add prognostic value to the current R-ISS classification of NDMM pts. Methods: We evaluated all NDMM pts seen at the Mayo Clinic, Rochester from 2009-2017 who had their peripheral blood samples evaluated by 6-color MFC prior to therapy. The cPCs detected were reported as the number of clonal events/150,000 collected total events. Survival analysis was performed by the Kaplan-Meier method and differences assessed using the log rank test. Results: This cohort consisted of 566 consecutive pts with NDMM with a median age of 66 years (27-95). The distribution of the R-ISS classification of this cohort is as follows: Stage 1- 128 (23%) pts, Stage 2- 369 (65%) pts and Stage 3- 69 (12%) pts. The median number of cPCs was 59 (0-46,412) / 150,000 events. The median time-to-next-treatment (TTNT) and overall survival (OS) for pts with ≥400 cPCs (n = 140, 25%) was 19 months and 46 months compared with 34 months and 77 months for those with < 400 cPCs respectively (n = 426, 75%) (p < 0.001 for both). The median TTNT and OS for pts based on their R-ISS classification as well as with and without the presence of ≥400 cPCs by MFC was as follows in the following Table. Conclusions: Quantifying ≥400 cPCs/150,000 analyzed events by MFC can potentially upstage the R-ISS classification of a subset of NDMM pts with stage I and II disease and identify those pts with a worse than expected survival outcome.[Table: see text]

Clinical and cytogenetic features of nonsecretory multiple myeloma (NSMM) in the era of novel agent induction therapy: The Mayo Clinic experience

e19519

Background: NSMM is a rare subtype of myeloma that has not been well characterized in the era of novel agent induction therapy. Thus, we evaluated the clinical and cytogenetic features of patients with newly diagnosed NSMM evaluated at our institution. Methods: We evaluated all NSMM patients seen at the Mayo Clinic, Rochester from 2008-2017 based on the absence of a detectable monoclonal protein in their serum and urine electrophoresis and having a concurrent involved serum immunoglobulin light chain of less than 5 mg/dL. Survival analysis was performed by the Kaplan-Meier method and clinical and cytogenetic features were reported descriptively. Results: This cohort consisted of 30 consecutive patients with NSMM with a median age of 62 years (40-79) of which 16 (53%) were male. The median bone marrow plasma cell involvement was 70% (Range: 0 – 100). There were 3/25 (12%) patients who presented with a creatinine of 2 mg/dL or greater and 6/23 (26%) patients who presented with hypercalcemia (11 mg/dL or greater). The ISS classification of this cohort is as follows: Stage 1- 8 (36%) patients, Stage 2- 3 (14%) patients and Stage 3- 11 (50%) patients. There were 6 (21%) out of 28 patients with high risk cytogenetics (either del 17p, t(4;14), t(14;16) or t(14;20). The distribution of primary cytogenetic abnormalities among this cohort was as follows: t(11;14) – 16 (57%), t(4;14) – 1 (4%), trisomies – 6 (21%) and other - 5 (13%). The median overall survival (OS) for patients in this cohort was 59 months (95% CI: 34 – 64). In comparison to a control cohort of newly diagnosed secretory myeloma patients matched for age, gender and year of diagnosis in a 1:2 ratio, the median OS was worse for the NSMM cohort but this was not statistically significant (59 vs. 92 months, p = 0.257). Conclusions: Patients diagnosed with NSMM had a predisposition towards having a t(11;14) primary cytogenetic abnormality. In the era of novel agent induction therapy, they may have a survival outcome that may be worse than newly diagnosed secretory myeloma patients.

Implications and outcomes of MRD-negative multiple myeloma patients with immunofixation positivity

8034

Background: Minimal residual disease (MRD) assessment in multiple myeloma (MM) has improved our ability to assess disease activity, resulting in more advanced prognostication. While MRD assessment remains confined to the bone marrow (BM) plasma cell population, serum studies including immunofixation (IFE) are required to complete response evaluation. The significance of those who are MRDneg yet have detectable monoclonal protein through IFE remains unclear. Methods: We retrospectively studied 256 MM patients who had MRD assessment via the Euroflow multiparametric flow cytometry on the BM with concomitant serum IFE testing. Patients who were MRDneg were included in the study. Outcomes included probability of disease progression (PD) at 1 year. The Cox-proportional hazards model was used to compare probability of PD among different groups. Time to progression (TTP) was calculated as the difference from date of MFC analysis to PD in months. Results: Among the entire cohort, 178 (70%) patients were MRDneg and median follow-up from MRD assessment was 6.3 months. Among these patients, 74 (42%) had a positive IFE at the time of MRD analysis. Within the MRDneg/IFEpos group, 31 (42%) patients remained IFEpos after a median follow up of 5.5 mo from initial MRD/IFE testing while 34 patients eventually became IFEneg after a median of 2.8 mo with no subsequent IFE available in 9 patients. The 1 year probability of PD in the MRDneg/IFEneg group was 20% compared to 41% in the MRDneg/IFEpos group (P < 0.01, Wilcoxon test). When comparing subsequent IFE status in those who were MRDneg/IFEpos, those who remained IFEpos had a trend towards shorter TTP compared to patients who later became IFEneg. Conclusions: Persistent monoclonal protein in the face of MRD negativity predicts for a shorter TTP. This likely reflects persistent disease that was not sampled on the BM aspirate in many of these patients compared to those who eventually become IFEneg with a trend towards longer TTP owing to the prolonged half-life and therefore clearance of M protein. This supports the current strategy of assessing for MRD at the time of suspected complete response to reduce the chance of positive MRD tests and thus avoidance of multiple BM exams.

Outcomes of patients with light chain amyloidosis who had autologous stem cell transplantation with three or more organs involved

8011

Background: Literature suggests that three or more organ involvement is a contraindication for autologous stem cell transplant (ASCT) in light chain amyloidosis (AL). Most centers limit transplantation to patients who have no more than two organs significantly involved. Methods: We retrospectively reviewed all patients with AL Amyloidosis involving three or more organs and who had ASCT between 1996-2015 at Mayo clinic, Rochester, Minnesota. Results: Seventy five patients underwent ASCT with three or more organs involved. Median age at diagnosis was 54 years and 67% were males. The heart was involved in 95%, followed by kidneys (84%). Thirty eight patients (51%) had no induction treatment prior to ASCT. Full dose melphalan (200mg/m2) was given in 45%, and the remaining received a reduced dose (140mg/m2). Overall response rate (hematological) was 75%. The median progression-free (PFS) and overall survival (OS) were 16.3 and 68.9 months, respectively. The 100-day mortality was 16% and overall forty four patients (59%) died during the follow up period. The most common causes of death were cardiovascular events (32%) and progressive amyloidosis (25%). On multivariable analysis, predictors for PFS were Mayo stage III/IV (RR 3.3, P = 0.0012) and hematological response (≥VGPR, RR 0.4, P = 0.012). An NT-ProBNP level of ≥2000 pg/ml was an independent predictor for shorter PFS (RR 2.6, P = 0.013). Predictors for OS included any hematological response (RR 0.1, P < 0.0001) and Mayo stage III/IV (RR 7, P < 0.0001). When looking at the NT-ProBNP, a level ≥2000 was prognostic (RR 5.5, P = 0.001). Number of organs involved (3 vs. 4-5) was not significant in either PFS or OS. Conclusions: We conclude that the high prevalence of cardiac involvement is the main driver for the poor outcome in patients who have three or more organs involved. Using selection criteria defined for safe transplantation in cardiac amyloidosis should result in low therapy-related mortality independent of the number of organs involved. The concept of considering patients with three organs involved ineligible for stem cell transplantation should be abandoned.

Rituximab-based maintenance therapy in Waldenström macroglobulinemia: A case control study

7559

Background: Waldenström macroglobulinemia (WM) is a rare indolent lymphoma commonly treated with rituximab (R)-based therapy. The use of rituximab maintenance (mR) in WM is controversial. We present a case-control study of patients (pts) with WM treated with mR. Methods: Pts evaluated at Mayo Clinic, Rochester with active WM that received mR between 1/2000 & 6/2018 were included. Cases comprised pts who received mR following R-based induction as primary therapy. Cases were matched based on the time of diagnosis in 1:2 ratio with a control group treated with R-based primary induction therapy without mR. Time to event analyses were performed from initiation of R-based induction. Results: Of 776 pts with active WM, 42 (5%) cases received mR and 84 pts were selected as controls. The median follow-up and the proportion of high risk pts were comparable between the two cohorts (Table). Pts in the mR cohort show a trend toward longer time to next therapy (TTNT) and a significantly longer overall survival (OS) compared to the control group (Table). The R-based induction therapies were comparable in the two cohorts (p = 0.6). Median duration of mR was 1.9 yrs (95% CI 1.6-2) and mR was used most frequently every (q) 2 (range 1-6) months. Of the 42 mR pts, 25 (60%) received an R-based combination for induction and 17 (40%) received R monotherapy as induction. Five (12%) pts discontinued mR due to toxicity, infections were reported in 13 pts (31%) during mR therapy and 3 pts (7%) received IVIg infusions for recurrent infections. Conclusions: R-based induction followed by mR demonstrates a longer OS in WM compared to R-treated control population not receiving mR, albeit at a high rate of infections. Despite limitations of a retrospective study, with a heterogeneously treated cohort, these data add to the body of literature supporting Rituximab maintenance. Results from an ongoing randomized controlled trial are awaited. [Table: see text]

Continued improvement in survival in multiple myeloma (MM) including high-risk patients

8039

Background: Treatment of MM has evolved significantly over the past decade, with increasing use of multi-drug combinations for initial therapy. In addition, supportive care approaches have also improved. We examined how these improvements have translated to survival outcomes in patients with newly diagnosed MM. Methods: Patients (n=3449) with a diagnosis of MM made between 2004 and 2017 and seen at Mayo Clinic within six months of the diagnosis, were included in this analysis. Patients were divided into three groups based on the year of diagnosis; group 1- 2004-07 (n=831), group 2-2008-12 (n=1161), and group 3-2013-17 (n=1457). Survival of the groups were estimated using Kaplan-Meier method, and compared using log rank test. Results: The median age was 64 years (22 to 96); 60% were male and 40% were female. 14% were >75 years, 33% were aged 65-75 and 53% were <65 years. The median overall survival for the whole cohort was 5.7 years (95%CI; 5.4, 6.3). The median OS for the groups 1, 2 and 3 were 3.9, 6.3 and NR, respectively; p<0.001. The 4-year survival estimates were 50%, 62%, and 75%, respectively. We then explored the improvements in patient subgroups. While all patients experienced improvements in OS over time, improvement in group 3 was most prominent for those >75 years. In patients <65 years, the 4-yr OS for groups 1, 2 and 3 were 57, 71, and 79% respectively. In patients 65-75 years of age, the 4-yr OS for groups 1, 2 and 3 were 48, 60, and 75% respectively. In patients >75 years, the 4-yr OS for groups 1, 2 and 3 were 24, 35, and 56% respectively. While patients with high-risk disease did not see as much benefit in the earlier period, substantial progress was seen in the last group. The 3-yr OS for patients with high-risk cytogenetics were 52, 55, and 73% for groups 1, 2 and 3 compared to 67, 75, and 85% for standard-risk cytogenetics respectively. 2067 patients were staged according to the International Staging System and the median OS for stages 1, 2 and 3 were 6.5, 4.6 and 2.4 in group 1; 9.2, 6.6 and 3.5 in group 2 and NR for any of the stages in group 3. Conclusions: The results confirm continued improvement in survival of newly diagnosed multiple myeloma patients, including elderly and high-risk MM.

Outcomes of Patients with Light Chain Amyloidosis Who Had Autologous Stem Cell Transplantation with 3 or More Organs Involved

Prior reports have suggested that 3 or more organs involved is a contraindication for autologous stem cell transplant (ASCT) in amyloid light chain (AL) amyloidosis. Therefore, most centers limit transplantation to patients who have no more than 2 organs significantly involved. We retrospectively reviewed all patients with AL amyloidosis with ≥3 involved organs and who had ASCT between 1996 and 2015 at Mayo Clinic, Rochester, Minnesota to assess transplant safety and outcomes. Seventy-five patients with ≥3 organs involved underwent ASCT. Median age at diagnosis was 54 years, and 67% were men. The heart was involved in 95%, followed by the kidneys (84%). Thirty-eight patients (51%) had no induction treatment before ASCT. Full-dose melphalan (200 mg/m²) was given in 45%, and the remainder received 140 mg/m². Overall hematologic response rate was 75%. The median progression-free survival (PFS) and overall survival (OS) were 16 and 68 months, respectively. The 100-day mortality was 16%, and 44 patients (59%) died during follow-up. The most common causes of death were cardiovascular events (32%) and progressive amyloidosis (25%). On multivariable analysis, predictors for PFS were Mayo 2012 stage III/IV (relative risk [RR], 3.3; P = .0012) and hematologic response (at least very good partial response; RR, .4; P = .012). An N-terminal pro-brain natriuretic peptide (NT-proBNP) level of ≥2000 pg/mL was an independent predictor for shorter PFS (RR, 2.6; P = .013). Predictors for OS included any hematologic response (RR, .12; P = .0015), melphalan 200 mg/m² (RR, .2; P = .014), and Mayo 2012 stage III/IV (RR, 7.7; P = .0002). An NT-proBNP level ≥ 2000 pg/mL was a powerful predictor of OS (RR, 4; P = .013). The number of organs involved (3 versus >3) did not significantly impact PFS or OS. We conclude that the high prevalence and severity of cardiac involvement are the main drivers for the poor outcome in patients who have ≥3 organs involved. Using selection criteria defined for safe transplantation in cardiac amyloidosis should result in low therapy-related mortality independent of the number of organs involved. The severity of cardiac involvement should be the major criterion for transplanting patients with AL amyloidosis that have ≥3 organs involved and not merely the number of organs involved.

Impact of prior diagnosis of monoclonal gammopathy on outcomes in newly diagnosed multiple myeloma

Multiple myeloma (MM) is consistently preceded by monoclonal gammopathy of undetermined significance (MGUS), smoldering myeloma (SMM), or solitary plasmacytoma (SPC). There is a lack of data regarding impact of these pre-existing monoclonal gammopathies (MGs) on MM outcomes. Patients with prior diagnosis of MGUS, SMM, or PC from 1973 to 2015 (cases) were identified from our institution's database and compared to those without a known MG (controls). The primary outcome of interest was overall survival (OS). Multivariate analysis was performed to ascertain factors impacting all-cause mortality. We identified 774 patients with a prior diagnosis of MGUS, SMM or SPC (cases) and a control population (1:2) matched for the year of diagnosis (n = 1548). After a median follow-up of 81 months, the cases showed a longer median OS than the controls (71 months vs. 56 months). The improved OS was limited to those with a known prior diagnosis of SMM (80 months) and SPC (95 months), compared to MGUS (60 months). Multivariable analysis revealed that MM patients with known prior MG had less overall mortality than those without, and this was limited to prior SMM/SPC group (HR 0.68, 95% CI: 0.50-0.93), as compared to the MGUS group (HR 0.83, 95% CI: 0.66-1.05).

Rapid assessment of hyperdiploidy in plasma cell disorders using a novel multi-parametric flow cytometry method

Trisomies of odd numbered chromosomes are seen in nearly half of patients with multiple myeloma (MM) and typically correlate with a hyperdiploid state and better overall survival (OS). We compared DNA ploidy of monoclonal plasma cells (as a surrogate for the presence of trisomies) assessed simultaneously by PCPRO (plasma cell proliferative index), a novel method that estimates DNA index by multi-parametric flow cytometry to fluorescence in situ hybridization (FISH) in 1703 patients with plasma cell disorders. The distribution of ploidy was hyperdiploid: 759 (45%), diploid 765 (45%), hypodiploid: 71 (4%), tetraploid/near-tetraploid: 108 (6%). FISH identified trisomies in 82% (621/756) of patients with hyperdiploidy by PCPRO and no trisomy by FISH was observed in 88% (730/834) of patients without hyperdiploidy. 95% (795/834) of patients without hyperdiploidy on PCPRO had one or less trisomy by FISH. Sensitivity and specificity of PCPRO for detecting hyperdiploidy was 86% (621/725) and 84% (730/865), respectively. Sensitivity increased to 94% (579/618) for patients with more than one trisomy. Newly diagnosed MM patients with hyperdiploidy on PCPRO (147/275) had better OS compared to nonhyperdiploid patients (median not reached vs 59 months, P = 0.008) and better progression free survival (median: 33 vs 23 months, P = 0.03). Within the hyperdiploidy group, patients with high-hyperdiploidy (DNA index: 1.19-1.50) versus those with low-hyperdiploidy (DNA index: 1.05-1.18) had superior OS (3 year OS of 88% vs 68% P = 0.03). Ploidy assessment by flow cytometry can provide rapid, valuable prognostic information and also reduces the number of copy number FISH probes required and hence the cost of FISH.

A Modern Primer on Light Chain Amyloidosis in 592 Patients With Mass Spectrometry-Verified Typing

OBJECTIVE

To describe the clinical and laboratory characteristics of patients with meticulously typed light chain (AL) amyloidosis.

PATIENTS AND METHODS

Patients (N=592) with biopsy-proven, mass spectrometry-confirmed AL amyloidosis diagnosed from January 1, 2008, through August 31, 2015, were included.

RESULTS

The median patient age at diagnosis was 63 years. Thirty-four percent of patients (n=204) had isolated organ involvement, mostly heart (19% [n=115]) followed by kidney (9% [n=53]). In contrast, 25% (n=146) had more than 2 involved organs. Patients with isolated cardiac involvement had similar cardiac dysfunction compared with those with nonisolated cardiac amyloidosis. In contrast, isolated renal involvement was associated with increased proteinuria and higher estimated glomerular filtration rate compared with nonisolated renal amyloidosis. Serum and urine immunofixation electrophoresis results were positive in 80% and 88% of patients, respectively, with 94% of patients having at least 1 positive immunofixation electrophoresis result (serum or urine). The serum free light chain ratio was abnormal in 91% of patients. When all monoclonal protein studies were combined, only 1 patient (0.2%) had normal results. The 1- and 5-year survival rates were 65% and 46%, respectively. Survival of patients with cardiac amyloidosis was not influenced by the number of involved organs (1 vs >1 organ), emphasizing the prognostic significance of cardiac involvement.

CONCLUSION

When mass spectrometry is used to definitively type amyloid, only a fraction of a percent of patients with AL have negative monoclonal protein studies, unlike historical reports. Patient characteristics and outcomes of accurately typed patients are described.

Peripheral blood biomarkers of early immune reconstitution in newly diagnosed multiple myeloma

Peripheral blood biomarkers of tumor microenvironment and immune surveillance are independent prognostic factors in multiple myeloma. The timing and prognostic impact of immune reconstitution has been studied after autologous hematopoietic stem cell transplantation, less is known about its significance in newly diagnosed multiple myeloma. We studied absolute lymphocyte (ALC) and absolute monocyte (AMC) counts at the time of treatment initiation and 1 month thereafter in 771 newly diagnosed patients. Two hundred and thirty-four patients (31%) had evidence of immune dysregulation at baseline (abnormal biomarkers). Eighty-seven of these patients (37%) recovered normal biomarkers at 1 month (early immune reconstitution). The absence of immune dysregulation at baseline (compared to the presence thereof) was associated with better overall survival (HR 0.77, 95% CI 0.61-0.97, P = 0.025, n = 771). The absence of immune dysregulation at 1 month (compared to the persistence or development thereof) was associated with better overall survival (HR 0.63, 95% CI 0.50-0.80, P < 0.001, n = 771). Early immune reconstitution (compared to the persistence or development of immune dysregulation) was associated with better overall survival (HR 0.62, 95% CI 0.43-0.92, P = 0.016, n = 771). Cytogenetic high-risk disease was negatively, and treatment with immunomodulators positively, associated with early immune reconstitution. The presence or development of immune dysregulation in newly diagnosed multiple myeloma is an independent risk factor. The favorable impact of early immune reconstitution suggests immune dysregulation to be a potentially modifiable risk factor that may be exploited for therapeutic benefit.

Substratification of patients with newly diagnosed standard-risk multiple myeloma

Despite the absence of high-risk cytogenetics and lower International Staging System (ISS) stages, a subset of patients with multiple myeloma (MM) experience poor overall survival (OS). We studied 1461 patients with newly diagnosed MM to identify patient and disease characteristics that predict a high-risk phenotype among standard-risk patients. Fifty-six percent of all patients presented with standard-risk disease. Among them, advanced age, extremes of body mass index, non-hyperdiploid karyotype and abnormal lymphocyte counts were associated with worse OS. Standard-risk patients with 0-1 of these adverse factors (hazard ratio [HR] 0·32, 95% confidence interval [CI] 0·24-0·43, P < 0·001) and 2 adverse factors (HR 0·54, 95% CI 0·41-0·72, P < 0·001) experienced better OS than high-risk patients. Two or more adverse factors were present in 17% of standard-risk patients and were associated with OS comparable to high-risk patients (HR 0·91, 95% CI 0·67-1·24, P = 0·548). Predictive power among standard-risk patients was improved using score groups compared to ISS stages. Patients with standard-risk MM are a heterogeneous group with one in six patients experiencing OS comparable to high-risk disease. Patients at risk can be identified using readily available patient and disease characteristics. These findings emphasize the importance of accurate risk stratification and help explain part of the heterogeneity observed in clinical practice.

Overall survival of transplant eligible patients with newly diagnosed multiple myeloma: comparative effectiveness analysis of modern induction regimens on outcome

Overall survival (OS) of multiple myeloma has improved remarkably over time, with the recent Intergroupe Francophone du Myelome (IFM) 2009 randomized trial reporting a 4-year OS rate of approximately 82% in patients receiving modern therapy. However, survival estimates from clinical trials may overestimate outcomes seen in clinical practice even with the adjustment for age and other key characteristics. The purpose of this study was to determine the OS of myeloma patients seen in routine clinical practice who resembled the cohort studied in the IFM 2009 trial. A second goal was to conduct a brief comparative effectiveness analysis of bortezomib, lenalidomide, dexamethasone, and other major induction regimens used during the study period. We studied all patients with myeloma 65 years of age and younger, seen at the Mayo Clinic between January 1, 2010 and August 31, 2015, who had a stem cell harvest performed within 12 months of initial diagnosis. Patients with baseline serum creatinine >2 mg/dL were excluded. Five hundred and eighteen patients were studied. The 4-year OS rate was 82.3%, comparable to results achieved in the contemporaneous IFM randomized trial. The 4-year OS rates for standard and high-risk myeloma were 86.3% and 68.2%, respectively.

Utility and prognostic value of 18 F-FDG positron emission tomography-computed tomography scans in patients with newly diagnosed multiple myeloma

Positron emission tomography-computed tomography (PET-CT) can identify bony lesions, assess disease burden, and detect extramedullary disease (EMD) in patients with multiple myeloma. We retrospectively reviewed records of patients who underwent PET-CT within 60 days of a new diagnosis (before therapy commenced) to identify the nature and prognostic impact of PET-CT abnormalities. Patients (N = 313) were seen from April 2005 through June 2017. Of the 234 patients (75%) with focal lesions (FLs), 182 (58%) had at least 3 FLs, 38 (12%) had EMD, and 204 (65%) had documented myelomatous lytic lesions. The median maximum standardized uptake value (SUV_max ) for the entire cohort was 5.9 (range 1.5-48.3). Presence of at least 3 FLs and EMD predicted inferior overall survival (OS); median OS was 57.8 months for patients with 3 or more FLs and 103.6 months for patients with fewer than 3 FLs (P = .003). The median OS was 45.5 and 71.8 months for patients with and without EMD, respectively (P = .004). No clear SUV_max cutoff was predictive of progression-free survival or OS. PET-CT is a valuable tool for assessing disease burden and could provide prognostic information about a contemporary cohort of patients with newly diagnosed myeloma who received treatment with novel agents.

Relapse after complete response in newly diagnosed multiple myeloma: implications of duration of response and patterns of relapse

Achieving a complete response (CR) is associated with improved overall survival (OS) in multiple myeloma (MM), but data on duration of CR (DurCR) are limited. We evaluated 351 patients (2004-2016), achieving CR with first-line therapy. Patients with sustained DurCR ≥ 24 months (n = 177) had better OS; 150 vs. 81 months, p < 0.001. DurCR ≥ 24 months remained a significant predictor for OS (HR: 0.3, 95% CI: 0.2-0.5, p < 0.001) after adjusting for age, revised ISS stage, transplant and maintenance therapy. Landmark analysis at 24 months demonstrated similar results, OS: 150 vs. 83 months, p < 0.001. Survival benefit persisted even after loss of CR, with median OS being 89 vs. 56 months (p = 0.005), respectively. Patterns of loss of CR were heterogeneous, with biochemical relapse in 59 (25%); symptomatic relapse in 58 (24%); positive immunofixation/monoclonal protein rise not meeting relapse/progression criteria in 88 (37%) and abnormal free light chain ratio in LC MM in 34 (14%) patients. OS from start of first-line therapy was superior in patients starting second-line treatment for biochemical vs. symptomatic relapse (125 vs. 81 months, p = 0.001). This is likely attributable to underlying disease biology and prevention of end-organ damage by early treatment initiation, as benefit was independent of R-ISS stage.