Imaging flow cytometric detection of del(17p) in bone marrow and circulating plasma cells in multiple myeloma

BACKGROUND

Detection of del(17p) in myeloma is generally performed by fluorescence in situ hybridization (FISH) on a slide with analysis of up to 200 nuclei. The small cell sample analyzed makes this a low precision test. We report the utility of an automated FISH method, called "immuno-flowFISH", to detect plasma cells with adverse prognostic risk del(17p) in bone marrow and blood samples of patients with myeloma.

METHODS

Bone marrow (n = 31) and blood (n = 19) samples from 35 patients with myeloma were analyzed using immuno-flowFISH. Plasma cells were identified by CD38/CD138-immunophenotypic gating and assessed for the 17p locus and centromere of chromosome 17. Cells were acquired on an AMNIS ImageStreamX MkII imaging flow cytometer using INSPIRE software.

RESULTS

Chromosome 17 abnormalities were identified in CD38/CD138-positive cells in bone marrow (6/31) and blood (4/19) samples when the percent plasma cell burden ranged from 0.03% to 100% of cells. Abnormalities could be identified in 14.5%-100% of plasma cells.

CONCLUSIONS

The "immuno-flowFISH" imaging flow cytometric method could detect del(17p) in plasma cells in both bone marrow and blood samples of myeloma patients. This method was also able to detect gains and losses of chromosome 17, which are also of prognostic significance. The lowest levels of 0.009% (bone marrow) and 0.001% (blood) for chromosome 17 abnormalities was below the detection limit of current FISH method. This method offers potential as a new means of identifying these prognostically important chromosomal defects, even when only rare cells are present and for serial disease monitoring.

Venetoclax for the treatment of multiple myeloma: Outcomes outside of clinical trials

Multiple myeloma (MM) remains an incurable disease despite incorporation of novel agents. Venetoclax, a B-cell lymphoma 2 (BCL-2) inhibitor is approved for some hematologic malignancies but not yet for MM, although clinical trials have shown efficacy in patients with MM, particularly those harboring t(11;14). We reviewed the medical records of relapsed and/or refractory MM patients to study the efficacy and safety of venetoclax used outside of clinical trials at Mayo Clinic between December, 2016 and March, 2019. The data cut-off date was August 06, 2020. We identified 56 patients of whom 42 (75%) harbored t(11;14). The median number of prior therapies was six (range 1-15) and 14% of patients had received ≥10 prior lines of therapy. Fifty-three (95%) patients were refractory to an immunomodulatory drug and proteasome inhibitor. Venetoclax was used as monotherapy or doublet, in combination with dexamethasone in 55% (n = 31) and a triplet or quadruplet in 45% of patients. No patient experienced tumor lysis syndrome. Overall response rate in 52 evaluable patients was 44%. The median time to best response was 2 months and median duration of response was 13.6 months. The median PFS for the entire cohort was 5.8 (95% CI 4.9-10.3) months and median OS was 28.4 (95% CI 14.6-not reached) months. The presence of t(11;14) was associated with improved PFS (median 9.7 months vs. 4.2 months, p = 0.019) and OS (median not reached vs. 10.8 9 months, p = 0.015). Venetoclax demonstrates encouraging activity in heavily-treated patients with relapsed/refractory MM, particularly the t(11;14) patient-population.

Long-term Outcomes of Sequential Hematopoietic Stem Cell Transplantation and Kidney Transplantation: Single-center Experience

BACKGROUND

Experience with sequential hematopoietic stem cell transplant (HSCT) and kidney transplant (KT) is limited.

METHODS

We conducted a retrospective observational study of adult patients who underwent both HSCT and KT at our center, with a median follow-up of 11 y.

RESULTS

In our 54 patients cohort (94% autologous HSCT), 36 (67%) patients received HSCT first followed by KT, while 18 (33%) received KT before HSCT. In both groups, AL amyloidosis represented 50% of hematologic diagnosis. Only 4 patients expired due to hematologic disease relapse (2 patients in each group) and only 3 allografts were lost due to hematologic disease recurrence (HSCT first n = 1 and KT first n = 2). Overall 1, 5, and 10 y death-censored graft survival rates were 94%, 94%, and 94%, respectively, for the HSCT first group and 89%, 89%, and 75%, respectively, for the KT first group. Overall 1, 5, and 10 y patients survival rates were 100%, 97% and 90%, respectively, for the HSCT first group and 100%, 76%, and 63%, respectively, for the KT first group.

CONCLUSIONS

Our study supports safety of sequential KT and HSCT, with improved overall patient survival compared to recipients of HSCT remaining on dialysis and good long-term kidney allograft outcome.

A randomized, open-label, phase 3 study of low-dose selinexor and lenalidomide (Len) versus len maintenance post autologous stem cell transplant (ASCT) for newly diagnosed multiple myeloma (NDMM): ALLG MM23, Sealand

TPS8055

Background: Len maintenance post ASCT is standard of care for patients (pts) with NDMM. Deep responses (CR or better) post ASCT correlates with better progression free survival (PFS). In a meta-analysis of len maintenance post ASCT (McCarthy PL et al. J Clin Oncol. 2017), only 10.7% of pts achieve CR post ASCT, and 72% of pts who discontinued len maintenance did so because of progressive disease (PD). Selinexor is a selective inhibitor of nuclear export that blocks exportin 1, thus retaining tumour suppressor proteins within the nucleus while blocking proto-oncoprotein translation. It is approved in combination with bortezomib and dexamethasone (dex) for pts with MM who have had at least 1 prior line of treatment, or with dex for pts with penta-refractory MM by the FDA. The oral bioavailability and weekly schedule of selinexor makes it suitable in combination with len for maintenance therapy. Given the encouraging activity (ORR 92%) and tolerability of selinexor, len and dex from the phase 1b/2 STOMP study, we hypothesise that combination low-dose selinexor and len (XR) will be well tolerated and effective, increasing CR and MRD negativity rate post ASCT, thus prolonging PFS compared to len. Methods: ALLG MM23 SeaLAND, is an ongoing randomised, multi-centre, phase 3 trial. Eligible pts ( > 17 years of age) have measurable disease, have undergone 3-6 cycles (C) of induction containing a proteasome inhibitor (PI) and/or immunomodulatory drug and recovered post melphalan-conditioned ASCT with adequate haematopoiesis, renal and liver function, and with ECOG performance status. Registration occurs prior to ASCT with screening between 75 to 115 days post ASCT. The study includes a lead-in safety phase of 20 patients with XR: Len 10mg daily days 1 to 21 and Selinexor 40mg weekly in a 28-day cycle. If well tolerated, Selinexor escalates to 60mg po weekly from C2 and Len to 15mg po daily from C4. Two safety reviews will occur after the 10th and 20th patients completes C2, respectively. Upon meeting safety criteria, a sample size of 290 pts will be randomised 1:1 to XR or lenalidomide (R). Therapy will continue until PD. The primary endpoint is PFS at 3 years post randomisation. Secondary endpoints include ORR and MRD-negativity rate (International Myeloma Working Group Response Criteria), PFS on next treatment line (PFS2), OS, safety and tolerability, quality of life, and cost effectiveness. Main analysis occurs after 232 patients complete 3-years of follow-up. Exploratory objective is to correlate immunological and molecular profiles to treatment response and resistance. ALLG MM23 SeaLAND is a multisite bi-national investigator-initiated trial lead by Australia and New Zealand’s national cooperative group, the Australasian Leukaemia & Lymphoma Group. Clinical trial registration: ACTRN12620000291987p. Clinical trial information: 12620000291987.

Immunoglobulin light chain amyloidosis diagnosis and treatment algorithm 2021

Immunoglobulin light chain amyloidosis (AL) commonly presents with nephrotic range proteinuria, heart failure with preserved ejection fraction, nondiabetic peripheral neuropathy, unexplained hepatomegaly or diarrhea, and should be considered in patients presenting with these symptoms. More importantly, patients being monitored for smoldering multiple myeloma and a monoclonal gammopathy of undetermined significance (MGUS) are at risk for developing AL amyloidosis. MGUS and myeloma patients that have atypical features, including unexplained weight loss; lower extremity edema, early satiety, and dyspnea on exertion should be considered at risk for light chain amyloidosis. Overlooking the diagnosis of light chain amyloidosis leading to therapy delay is common, and it represents an error of diagnostic consideration. Herein we provide a review of established and investigational treatments for patients with AL amyloidosis and provide algorithms for workup and management of these patients.

Comparison of the current renal staging, progression and response criteria to predict renal survival in AL amyloidosis using a Mayo cohort

Three sets of criteria (International Society of Amyloidosis [ISA], Palladini and Kastritis) were independently developed for staging, progression and response criteria to predict renal survival in patients with AL amyloidosis. We evaluated these criteria using a cohort of 495 newly diagnosed AL amyloidosis patients with renal involvement using time to event competing risk analysis at baseline, 3, 6 and 12 months after treatment. Only Palladini and Kastritis had a staging system and both predicted a higher risk of end stage renal disease (ESRD) in the stage III vs stage I patients but only the Palladini model was predictive for stage II patients. At 3 months, risk of ESRD was significantly higher for Palladini and ISA renal progression (hazard ratio [HR] 2.8 [95% CI: 1.5-5.3, p = .001] and 2.5 [CI: 1.4-4.6, p = .004, respectively]), but renal response was not significantly protective; conversely, the risk of ESRD was not significantly higher for the Kastritis renal progression, but was significantly protective for the Kastritis renal responders (HR 0.38 [95% CI: 0.17-0.84], p = .017). Both progression and response with ISA, Palladini and Kastritis criteria were predictive of ESRD at 6 months and 12 months. While the Palladini staging criteria at baseline, and the ISA and Palladini criteria for progression at 3 months performed better than the Kastritis criteria at baseline and 3 months post-treatment, the Kastritis criteria performed better for response 3 months after treatment. All three sets of criteria performed well at and after 6 months post-treatment. These differences are important when choosing endpoints for clinical trials.

Immune-mediated neuromuscular complications of graft-versus-host disease

INTRODUCTION/AIMS

We aimed to describe the clinical phenotype, histopathological findings and overall survival (OS) of the immune-mediated neuromuscular complications of graft-versus-host disease (GVHD).

METHODS

We conducted a retrospective chart review of adult patients presenting with immune-mediated neuromuscular complications of GVHD to Mayo Clinic, between April 2013 and July 2018.We collected clinical and laboratory characteristics, histopathological findings, response to treatment and survival data.

RESULTS

We identified 20 patients with a mean age at presentation of 55 y. Mean time from transplant to neurological presentation was 14 mo. Myositis was the most common complication seen in 17 patients, manifesting with predominantly axial and/or proximal weakness. Eleven patients had a muscle biopsy showing diffuse perimysial, predominantly macrophagic infiltration in 10, 3 of them with perimysial perivascular lymphocytic collections, and endomysial and perimysial lymphocytic infiltration in 1. Only two patients had a neuropathic complication: one each with acute inflammatory demyelinating polyradiculoneuropathy and neuralgic amyotrophy. A single patient had a myasthenic syndrome presenting with fluctuating foot drop. Nineteen patients were treated and all responded to immunosuppressive agents; however, 11 had further GVHD flares requiring escalation of therapy. After a median follow-up of 83 mo, seven (35%) patients died: five from progressive GVHD and two from infections. The 5-y OS from time of transplant was 68%.

DISCUSSION

Myositis is the most common immune-mediated neuromuscular complication of GVHD while peripheral neuropathy and myasthenic syndromes appear less common. The macrophage-predominant infiltration on muscle biopsy deserves further study to better clarify the role of macrophages in GVHD pathogenesis.

Depth of response prior to autologous stem cell transplantation predicts survival in light chain amyloidosis

The goal of therapy in AL amyloidosis is to inhibit further production of the amyloidogenic light chains, thereby allowing organ recovery and improving survival. We aimed to assess the impact of depth of hematologic response prior to ASCT on survival. We conducted a retrospective study of 128 newly diagnosed AL amyloidosis patients who received induction prior to ASCT between January 2007 and August 2017 at Mayo Clinic. The overall response rate to induction was 86% (CR 18%, VGPR 31% and PR 38%). With a median follow up of 52 months, the median PFS and OS was 48.5 months and not reached, respectively. Response depth to induction therapy was associated with improved PFS and OS. The median PFS was not reached for patients achieving ≥VGPR prior to ASCT and 34.1 months for patients achieving PR or less (P = 0.0009). The median OS was longer in patients with deeper responses (not reached for ≥VGPR vs. 128 months for PR or less (P = 0.02)). On multivariable analysis, independent predictors of OS were melphalan conditioning dose (RR = 0.42; P = 0.036) and depth of response prior to transplant (RR 0.37; P = 0.0295). Hematologic response prior to transplant predicts improved post transplant outcomes in AL amyloidosis.

Depth of response prior to autologous stem cell transplantation to predict survival in light chain amyloidosis

8516

Background: The role of induction therapy prior to autologous stem cell transplant (ASCT) in immunoglobulin light chain (AL) amyloidosis remains controversial. Data on the prognostic impact of response to induction in a transplanted cohort are lacking. The aim of this study was to assess the impact of response to induction therapy on survival in patients undergoing ASCT for AL amyloidosis. Methods: We conducted a retrospective study of all newly diagnosed AL amyloidosis patients who received induction prior to ASCT between January 2007 and August 2017 at Mayo Clinic, Rochester, Minnesota. Patients receiving only corticosteroids prior to transplant were excluded as were those with an involved light chain of less than 5 mg/dL (not measurable for response). Results: 134 patients met inclusion criteria. The median age at diagnosis was 60 (range 36-74) and 85 (63%) were men. The most commonly used induction regimen was proteasome inhibitor-based (73.1%, n=98). The overall response rate to induction was 83% (complete response 17%, very good partial response 30% and partial response 36%). With a median follow up of 56.5 months, the median PFS and OS was 48.5 months and not reached, respectively. Response depth to induction therapy was associated with improved PFS and OS and was independent of the bone marrow plasma cell percentage. The median PFS was not reached for patients achieving ≥VGPR prior to ASCT and 33.8 months for patient achieving PR or less (P=0.001). The median OS was longer in patients with deeper responses (not reached for patients achieving ≥VGPR vs. 128 months for patients achieving PR or less (P=0.02). On multivariable analysis, independent predictors of OS were melphalan conditioning dose (RR= 0.38; P=0.018) and depth of response prior to transplant (RR 2.52; P=0.039). Conclusions: Hematologic response prior to transplant predicts post-transplant outcomes in patients with AL amyloidosis. [Table: see text]

The role of bone marrow biopsy in patients with plasma cell disorders: should all patients with a monoclonal protein be biopsied?

We conducted a retrospective review of multiple myeloma (MM), smoldering multiple myeloma (SMM), and monoclonal gammopathy of undetermined significance (MGUS) patients seen at Mayo Clinic to determine whether a bone marrow biopsy (BM) is necessary in all patients diagnosed with a monoclonal protein. A total of 2254 MM, 397 SMM, and 5836 MGUS patients were included in the study. A total of 29 (1.3%) MM patients “without CRAB/FLC” were identified where BM or advanced imaging was critical for diagnosis, 8 (0.3% MM cohort) of whom were diagnosed with MM solely on BM findings (plasma cells > 60%). Without BM or advanced imaging none of these patients would be classified low-risk MGUS. A total of 314 (79%) MGUS-like SMM patients were identified where classification of SMM was based on BM findings. Without BM 97 would be classified as low/low-intermediate-risk MGUS and 151 intermediate or high-risk MGUS; 66 had missing information precluding classification. Only three (<1% SMM cohort) were low-risk MGUS without abnormalities in hemoglobin, calcium, and renal function. In patients presenting with low-risk MGUS and normal hemoglobin, calcium, and renal function, the risk of missing a diagnosis of SMM and MM by omitting BM is <1%. BM should be deferred in these patients in preference to clinical and laboratory monitoring.

Hematopoietic score predicts outcomes in newly diagnosed multiple myeloma patients

Risk stratification of multiple myeloma (MM) at diagnosis is critical. We examined the ability of hematopoietic indices including mean corpuscular volume (MCV), hemoglobin (Hgb), and platelet (Plt) to predict outcomes. This was a retrospective study of patients treated at Mayo Clinic between January 2004 and April 2018. We incorporated three variables (Hgb < 10 g/dL, Plt < 150 × 10⁹ /L, and MCV > 96 fL), assigning a score of 1 to each. We identified 1540 newly diagnosed MM patients, of whom 707 (46%) had a score of 0, 513 (33%) had a score of 1, 260 (17%) had a score of 2, and 60 (4%) had a score of 3. The score risk stratified patients into four groups with differing survivals. The median PFS was 32.3 months for score 0, 24.8 months for score 1, 21.7 months for score 2, and 18.3 months for score 3, for P < .001. The median OS was 80.7 months for score 0, 59.9 months for score 1, 51.7 months for score 2, and 31.3 months for score 3, P < .0001. Predictors of OS on the multivariable analysis were age ≥ 65 (HR, 1.93; P < .0001), R-ISS stage (1-2 vs 3) (HR, 0.48; P < .0001), and hematopoietic score (0-2 vs 3) (HR, 0.51; P = .006). A hematopoietic score can predict survival in newly diagnosed myeloma patients.

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.

The Human Microbiota in Multiple Myeloma and Proteasome Inhibitors

The gut microbiota plays a significant role in health and disease, including cancer development and treatment. The importance of the gut microbiota in the efficacy and toxicity of novel therapies and immunotherapy is increasingly recognized. Plasma cells in multiple myeloma have the potential to survive in the gastrointestinal tract for long periods of time. The nature of the gut microbiota impacts the degree of antigen stimulation of these cells and may play a role in mutation development and clonal evolution. Furthermore, myeloma therapies such as proteasome inhibitors and alkylating agents, commonly used to treat patients, are frequently associated with gastrointestinal adverse events. Herein we review the gut microbiota and its role in hematopoiesis, pathogenesis of myeloma, and efficacy/toxicity of anti-myeloma therapies.

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.

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.

Autologous stem cell transplantation in patients with AL amyloidosis with impaired renal function

We retrospectively reviewed the impact of impaired renal function (eGFR < 45 ml/min/SA) on post-transplant outcomes in patients receiving ASCT for AL amyloidosis. Patients were grouped into two cohorts, those with normal renal function (NRF) eGFR ≥ 45 ml/min (n = 568) and those with impaired renal function (IRF) eGFR < 45 ml/min (n = 87). Patients with IRF had higher renal stage (>Stage 1: 100% IRF vs 37% NRF, p < 0.0001) and the majority received conditioning with melphalan <200 mg/m² (70% IRF vs 21% NRF, p < 0.0001). Forty-four patients (6.7%) required dialysis within 100 days of ASCT. Renal stage predicted for dialysis institution within 100 days of ASCT (3% Stage I vs 10% Stage II vs 22% Stage III, p < 0.0001). Dialysis within 100 days was higher in the IRF cohort (16% for IRF cohort vs 6% for NRF cohort, p = 0.0007. Patients with impaired renal function were more likely to be admitted to hospital (80% IRF vs 70% NRF, p = 0.03). The 100-day mortality was higher in the IRF cohort (14% IRF cohort vs 5% NRF cohort, p = 0.008). Median OS and PFS were similar between the two cohorts. Impaired renal function predicts for a higher rate of hospitalization, progression to dialysis and early mortality in patients receiving ASCT for AL amyloidosis.

Daratumumab for the treatment of AL amyloidosis

Autologous stem cell transplantation (ASCT) has been used as treatment for immunoglobulin light-chain (AL) amyloidosis for over two decades with improving outcomes; however, the majority of patients are not candidates for this therapy at diagnosis. Novel agents such as immunomodulatory drugs, proteasome inhibitors, and immunotherapy with monoclonal antibodies targeting CD38 have been adopted from the multiple myeloma spheres with encouraging results. Herein, we discuss the role of daratumumab, a monoclonal antibody to CD38, in the treatment of AL amyloidosis. We focus on its mechanism of action, tolerability, and the current published data on its use in AL amyloidosis. Early data from phase I and phase II studies show that daratumumab is tolerated well in this population and induces rapid and deep responses. Phase III trials are currently accruing and we envision daratumumab becoming a key component in the treatment of AL amyloidosis in the future.

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.

Therapy for relapsed multiple myeloma

Despite significant progress in our understanding and the development of novel therapies, most patients with multiple myeloma will experience relapse of their disease. Therapy of relapsed myeloma has improved due to the availability of novel agents that are highly active against the disease. However, the selection of therapy can be challenging due to the emergence of toxicities, comorbidities and frailty. In the following we discuss our approach to the treatment of the patient with relapsed myeloma.

Plasma cell proliferative index post-transplant is a powerful predictor of prognosis in myeloma patients failing to achieve a complete response

Myeloma patients failing to achieve a complete response post autologous stem cell transplantation are heterogeneous, some ultimately achieving deeper responses and prolonged remission, whilst others relapse rapidly with poor outcomes. We evaluated the prognostic impact of the plasma cell proliferative index (PCPI) post-therapy, in 382 patients with myeloma failing to achieve complete response at 100 days post-transplant. Sixty percent (n = 230) of patients had zero clonal or too few clonal plasma cells to accurately assess PCPI (No PCPI). The remaining 40% (n = 152) of patients had PCPI performed with 79% (n = 120) having a low PCPI and 21% (n = 32) having an elevated PCPI. Patients with an elevated PCPI had significantly shorter progression free and overall survival. The median PFS was 8 months for elevated PCPI vs. 19 months for low PCPI vs. 24 months for no PCPI (p < 0.0001). The median OS was 27 months for elevated PCPI vs. 79 months for low PCPI vs. not reached for no PCPI, p < 0.0001). On multivariable analysis post-therapy PCPI was an independent predictor of progression free and overall survival. The PCPI post-therapy is a powerful predictor of survival and risk stratifies myeloma patients failing to achieve complete response early in the disease course.

Prognostic Significance of Stringent Complete Response after Stem Cell Transplantation in Immunoglobulin Light Chain Amyloidosis

Hematologic response has emerged as a powerful prognostic factor for survival in patients with immunoglobulin light chain (AL) amyloidosis. Patients achieving a complete response (CR), based on serum and urine analysis, survive longest. However, data regarding the impact of bone marrow features post-therapy on response and survival are limited. We evaluated the impact of achieving a stringent CR (sCR), defined as undetectable bone marrow clonal plasma cells by flow cytometry, in patients with AL amyloidosis receiving an autologous stem cell transplant. A total of 573 consecutive patients transplanted for AL amyloidosis at the Mayo Clinic between April 2002 and August 2016 were included in the analysis. Of 540 patients in whom response was assessable, 220 patients (41%) achieved a CR, of whom 212 (96%) had a bone marrow biopsy at time of response assessment and were further analyzed for determination of sCR; 166 patients (78%) with a CR achieved an sCR, representing 31% of the whole cohort. Patients achieving a CR had a higher median percentage of bone marrow plasma cells (10% for CR versus 6% for sCR, P = .03), more patients with bone marrow plasma cells ≥ 10% (50% for CR versus 33% for sCR, P = .04), and were less likely to receive chemotherapy before transplantation (30% for CR versus 49% for sCR, P = .03) compared with those achieving sCR. Median overall survival for all patients achieving a CR was 175 months and was not statistically different between those achieving an sCR compared with those achieving a CR only (median not reached for sCR versus 175 months for CR, P = .65). Progression-free survival, however, was significantly shorter in patients failing to achieve an sCR (151 months for sCR versus 72 months for CR, P = .0003). Bone marrow examination post-transplant in AL amyloidosis is important and identifies patients who fail to achieve an sCR and progress earlier.

Autologous Stem Cell Transplant for Immunoglobulin Light Chain Amyloidosis Patients Aged 70 to 75

Autologous stem cell transplantation (ASCT) has been used in treatment for immunoglobulin light chain (AL) amyloidosis for over 2 decades and is generally reserved for patients younger than 70 years. Herein we report on outcomes of ASCT in a cohort of patients with AL amyloidosis aged 70 years or older. Between August of 2002 and April of 2017, 34 patients aged 70 years or older, with biopsy-proven AL amyloidosis, received an ASCT at the Mayo Clinic Rochester. Seventy percent of patients (n = 24) were transplanted within 6 months of diagnosis, and 74% (n = 25) received reduced-intensity conditioning with melphalan <200 mg/m². Sixty-five percent of patients (n = 22) required hospitalization with a median duration of hospital admission of 8 days. Common reasons for hospitalization included fever or infection (14%), cardiac arrhythmia (14%), nutritional support (24%), and volume overload (19%). Overall response rate was 75%, with a complete response seen in 25% of patients. Overall survival and progression-free survival for the cohort were 66 months and 40 months, respectively. One patient died within 100 days of transplant, representing a 3% 100-day mortality rate. ASCT is safe and efficacious in carefully screened patients aged 70 or above.

Stem Cell Transplantation for Light Chain Amyloidosis: Decreased Early Mortality Over Time

Purpose

Autologous stem-cell transplantation (ASCT) has been used in patients with immunoglobulin light chain (AL) amyloidosis for more than two decades. Early experience raised concerns regarding safety with high early-mortality rates.

Patients and Methods

We report 20 years of experience with ASCT for AL amyloidosis at the Mayo Clinic Rochester. In all, 672 consecutive patients receiving ASCT for AL amyloidosis were divided into three cohorts on the basis of date of transplantation (cohort 1, 1996-2002 [n = 124]; cohort 2, 2003-2009 [n = 302]; and cohort 3, 2010-2016 [n = 246]).

Results

The median age for the entire cohort was 59 years, with patients in cohort 3 being slightly older than those in the other two cohorts (60 v 58 v 54 years for cohorts 3, 2, and 1, respectively; P < .001). Fewer patients in cohort 3 had more than two organs involved (9% v 18% v 19% for cohorts 3, 2, and 1, respectively; P < .001). More patients received pretransplantation therapy in cohort 3 compared with earlier time periods (49% v 38% v 42% for cohorts 3, 2, and 1, respectively; P = .02). Hematologic response was higher in cohort 3 (84% v 79% v 69% for cohorts 3, 2, and 1, respectively; P = .002). Median overall survival for the entire cohort was 122 months and improved over time (not reached v 120 months v 75 months for cohorts 3, 2, and 1, respectively; P < .001). Treatment-related mortality declined over time (2.4% v 8.6% v 14.5% for cohorts 3, 2, and 1, respectively; P < .001). On multivariable analysis, conditioning dose, Mayo stage 2012, and hematologic response were independent predictors of survival.

Conclusion

ASCT is a highly effective therapy for AL amyloidosis. The improved survival and markedly reduced treatment-related mortality in eligible patients indicate that this will remain an important first-line option even in the era of treatment approaches that use novel agents.

Plasma cell proliferative index predicts outcome in immunoglobulin light chain amyloidosis treated with stem cell transplantation

The plasma cell proliferative index provides an insight into plasma cell biology in plasma cell disorders and is an important prognostic marker in myeloma and smoldering myeloma. We analyzed the prognostic impact of the plasma cell proliferative index in 513 patients with systemic immunoglobulin light chain (AL) amyloidosis undergoing stem cell transplantation at the Mayo Clinic between 1^st January 2003 and 31^st August 2016. Two cohorts were identified according to Low or Elevated plasma cell proliferative index. Patients with an Elevated plasma cell proliferative index had more cardiac involvement (56% vs. 44%; P=0.01), less renal involvement (55% vs. 70%; P=0.001), and were more likely to have 10% or over bone marrow plasma cells (58% vs. 32%; P<0.0001) compared to those with a Low plasma cell proliferative index. Both progression-free survival and overall survival were lower in patients with an Elevated compared to Low plasma cell proliferative index: median progression-free survival 44 vs. 95 months (P<0.0001) and median overall survival 102 vs. 143 months (P=0.0003). All-cause mortality at 100 days was higher in patients with an Elevated plasma cell proliferative index (elevated 10.3% vs. low 4.3%; P=0.008). On multivariate analysis Elevated plasma cell proliferative index was an independent prognostic factor for overall survival (Hazard Ratio 1.5, 95%CI: 1.1-2.1; P=0.021). The plasma cell proliferative index is an important prognostic tool in patients with AL amyloidosis undergoing stem cell transplant.

Light chain type predicts organ involvement and survival in AL amyloidosis patients receiving stem cell transplantation

We evaluated the impact of light chain type, lambda (λ) or kappa (κ), on disease features and outcomes in patients with immunoglobulin light chain (AL) amyloidosis receiving stem cell transplant at the Mayo Clinic between October 2002 and August 2016. Patients with λ AL amyloidosis had higher rates of renal and neurological involvement (λ 69% vs κ 57%, P = .02 and λ 16% vs κ 9%, P = .03, respectively). Patients with κ AL amyloidosis had more hepatic involvement (λ 7% vs κ 18%, P = .0003). Complete response rate was 43% for both groups and overall response rates were similar (λ 85% vs κ 91%, P = .12). Patients with κ light chain amyloidosis had better progression-free and overall survival (PFS: λ 74 months vs κ 101 months, P = .0064 and OS: λ 121 months vs κ not reached, P = .003). Mayo stage 2004 was more predictive of survival in the λ cohort (median OS of 143 months stage I vs 77 months stage II vs 33 months stage III, P < .0001) than in the κ cohort (median OS not reached for stage I and II and 102 months for stage III, P = .044). Conditioning dose predicted survival in the λ cohort only (median OS 149 months for melphalan 200 mg/m² vs 50 months for melphalan <200 mg/m², P < .0001; median OS κ not reached for melphalan 200 mg/m² or <200 mg/m², P = .38). On multivariate analysis, light chain type remained an independent predictor of survival. Light chain type predicts organ involvement and survival in patients with AL amyloidosis receiving stem cell transplant.