Amyloid arthropathy in smoldering myeloma: Do not take it lightly

We report a case of smoldering multiple myeloma patient who developed signs and symptoms consistent with polyarthritis. A PET-CT demonstrated marked FDG activity in multiple joints, concerning for inflammatory arthritis. Arthrocentesis from the glenohumeral joint was consistent with inflammatory synovial fluid with no evidence for infection or crystals. Congo-red stain of the synovial fluid was positive, and mass-spectrometry based amyloid typing was consistent with wild-type transthyretin type. The patient responded instantly to glucocorticoids. This case reports highlights the feasibility of non-tissue diagnosis of amyloidosis using body fluids and underscores the importance of accurate typing to avoid erroneous treatment

MASS-FIX for the detection of monoclonal proteins and light chain N-glycosylation in routine clinical practice: a cross-sectional study of 6315 patients

Immunoenrichment-based matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), termed MASS-FIX, offers several advantages over immunofixation for the detection and isotyping of serum monoclonal protein, including superior sensitivity and specificity, the ability to differentiate therapeutic monoclonal antibodies, and the rapid identification of light chain (LC) N-glycosylation. We identified 6315 patients with MASS-FIX performed at our institution since 2018. Of these, 4118 patients (65%) with a wide array of plasma cell disorders (PCD), including rare monoclonal gammopathies of clinical significance, had a positive MASS-FIX. Two-hundred twenty-one (5%) of the MASS-FIX positive patients had evidence of LC N-glycosylation, which was more commonly identified in IgM heavy chain isotype, kappa LC isotype, and in diagnoses of immunoglobulin light chain (AL) amyloidosis and cold agglutinin disease (CAD) compared to other PCD. This cross-sectional study describes the largest cohort of patients to undergo MASS-FIX in routine clinical practice. Our findings demonstrate the widespread utility of this assay, and confirm that LC N-glycosylation should prompt suspicion for AL amyloidosis and CAD in the appropriate clinical context.

Outcomes with different administration schedules of bortezomib in bortezomib, lenalidomide and dexamethasone (VRd) as first-line therapy in multiple myeloma

Induction therapy for multiple myeloma with bortezomib (Velcade), lenalidomide (Revlimid), and dexamethasone (d) (VRd) was traditionally administered as bortezomib given twice weekly on a 3 week cycle. A modified schedule of weekly bortezomib has been adopted over time to decrease treatment burden for patients and reduce treatment-emergent neuropathy. This study evaluates the response rates and outcomes with different schedules of bortezomib in VRd administered for first-line treatment for patients with newly diagnosed MM (NDMM). We retrospectively analyzed patients treated with upfront VRd from June 30th 2008 to December 31st 2018, for variations of bortezomib administration. Five hundred and fifty-five (555) NDMM patients met inclusion criteria; median age 63 years and 61% men. Bortezomib was administered twice weekly every 21 days in 43%, once weekly every 21 days in 41% and once weekly every 28 days in 16%. Though peripheral sensory neuropathy was more frequent with twice weekly dosing (P = .002), this group achieved shorter time to best response (P = .01). Weekly every 21-day treatment saw higher VGPR or better rates (P = .02). However, with median follow up time of 37 months (IQR 22-56), we found no difference in PFS or OS among the groups. While small differences in response rates were found among the varying administration schedules of bortezomib administration, there was no significant effect on PFS or OS. Given that VRd remains a first line standard of care option for newly diagnosed MM, in the absence of a large trial comparing bortezomib dosing schedule modifications, these results are helpful in supporting current practices of once weekly administration.

Characterization and prognostic implication of delayed complete response in AL amyloidosis

INTRODUCTION

Little is known on continued response following completion of therapy in light chain (AL) amyloidosis.

METHODS

We studied 373 AL amyloidosis patients who achieved complete response (CR) or very good partial response (VGPR) to first-line therapy.

RESULTS

By end of therapy (EOT), 46% of patients achieved a CR and 54% a VGPR. With no further therapy, 17.5% of patients were upstaged from VGPR to CR (delayed CR), with a median of 9 months. Compared with CR and VGPR at EOT, patients with a delayed CR were characterized by higher proportion of t(11;14) and lower rate of trisomies. Autologous stem cell transplant was more frequent in the delayed CR group. Patients with a delayed CR were characterized by minimal residual disease negativity and organ response rates similar to patients with CR at EOT and higher than patients achieving VGPR at EOT. Patients with a delayed CR had a longer PFS/OS compared to patients with CR or VGPR by EOT (median PFS 149 vs 92 vs 52 months, P < .001; 10-year OS 87% vs 71% vs 56%, P < .001).

CONCLUSIONS

This study characterizes delayed CR in AL amyloidosis, highlights its prognostic impact which is at least similar to those who achieved CR at EOT, and underlines another aspect of response monitoring.

Disease monitoring with quantitative serum IgA levels provides a more reliable response assessment in multiple myeloma patients

Unlike IgG monoclonal proteins (MCPs), IgA MCP quantification is unreliable due to beta-migration of IgA MCPs on serum protein electrophoresis (SPEP). The utility of nephelometric quantitative IgA (qIgA) to monitor IgA multiple myeloma (MM) is unclear. We retrospectively studied disease response kinetics using qIgA versus MCPs by SPEP, and developed and validated novel qIgA disease assessment criteria in 491 IgA MM patients. The SPEP MCP nadir occurred a median of 41 (IQR 0-102) days before the qIgA. The median time to achieve a partial response (PR) was shorter using standard IMWG versus qIgA response criteria (32 vs 58 days, p < 0.001). Stratification by qIgA criteria, unlike IMWG criteria, led to clear separation of the progression-free survival curves of patients achieving a PR or very good PR. There was a consistent trend toward earlier detection of disease progression using qIgA versus IMWG progression criteria. In conclusion, monitoring IgA MM using MCP-based IMWG criteria may be falsely reassuring, given that MCP levels on SPEP decrease faster than qIgA levels. The qIgA response criteria more accurately stratify patients based on the progression risk and may detect disease progression earlier, which may lead to more consistent measurement of trial endpoints and improved patient outcomes.

Coagulation Abnormalities in Light Chain Amyloidosis

OBJECTIVE

To assess the prevalence of coagulation abnormalities in patients with systemic light chain (AL) amyloidosis and their association with disease-related characteristics, disease progression, and survival.

PATIENTS AND METHODS

This is a retrospective study of patients with AL amyloidosis seen at Mayo Clinic, Rochester, Minnesota, from January 1, 2006, to December 31, 2015. We studied the association between abnormal coagulation parameters and baseline characteristics and their association with survival outcomes.

RESULTS

The study included 411 patients. Abnormalities at diagnosis included prolonged clotting times and coagulation factor deficiencies; prolonged prothrombin time (PT) and factor X (FX) deficiency were found in 19% (73 of 390) and 43% (177 of 411) of patients, respectively. The FX deficiency was associated with higher Mayo stage, involvement of more than 1 organ, liver and cardiac involvement, and greater than 10% bone marrow plasma cells. On univariate analysis, the risk for disease progression or death was higher in patients with abnormal values for PT and factor V, factor VII (FVII), FX, and factor XII compared with those with normal values. Prolonged PT and FVII and FX deficiencies were independent predictors of death after adjusting for Mayo stage and more than 1 organ involvement. Only 106 patients had repeat testing after treatment; no clear relationship was found between treatment response and changes in coagulation parameters.

CONCLUSION

Coagulation abnormalities occur in a significant proportion of patients with AL amyloidosis and are associated with advanced disease and inferior outcomes. Larger studies are needed to establish whether a relationship exists between treatment response and improvement in individual parameters.

Autologous stem cell transplantation for multiple myeloma patients aged ≥ 75 treated with novel agents

Autologous stem cell transplantation (ASCT) has been used for treating multiple myeloma (MM) for over three decades and is generally reserved for patients younger than 65. Herein we report on outcomes of outpatient ASCT in a cohort of patients with MM aged ≥75 years. Between October 2005 and August 2020, 50 patients aged ≥75 years, received an ASCT at Mayo Clinic, Rochester. Median time from diagnosis to ASCT was 6.85 months (IQR 5.2-10.52) and 50%. received reduced intensity conditioning with melphalan 140 mg/m². 48% of patients completed the ASCT without requiring hospitalization and 52% (n = 26) of patients required hospitalization with a median duration of hospital admission of 9 days (IQR 5-13). Reasons for hospitalization included fever or infection (32%), cardiac arrhythmia (36%), and dehydration (32%). Overall response rate was 100% with a complete response seen in 57% of patients. Median overall survival and progression free survival for the cohort were 82 months and 33 months, respectively. One patient died within 100 days of transplant representing a 2% 100-day mortality rate. ASCT is safe and efficacious in carefully selected MM patients aged 75 or above and we believe that age should not be an exclusion factor for ASCT in MM.

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.

Refining amyloid complete hematological response: Quantitative serum free light chains superior to ratio

Response assessment in light chain (AL) amyloidosis is based on serum and urine monoclonal protein studies. Newly diagnosed patients (n = 373) who achieved very good partial response or complete response (CR) to first line therapy were assessed for the survival impact of each of the monoclonal protein studies. At end of therapy (EOT), negative serum/urine immunofixation (IFE) was achieved in 61% of patients, 72% achieved normal serum free light chain ratio (sFLCR), and the median involved free light chain (iFLC) and difference between involved to uninvolved light chain (dFLC) were 17 mg/L and 5 mg/L, respectively. Overall, 46% of patients achieved a CR at EOT. At EOT, iFLC ≤20 mg/L and dFLC ≤10 mg/L were additive in survival discrimination to negative serum/urine IFE and were independent predictors of overall survival. In contrast, normalization of sFLCR did not add survival discrimination to serum/urine IFE and was not independent predictor of survival. We propose a new definition for hematological CR to include serum/urine IFE negativity plus iFLC ≤20 mg/L or dFLC ≤10 mg/L, instead of the current definition of serum/urine IFE negativity and normal sFLCR. Complete response using dFLC ≤10 mg/L had the best performance in those with significant renal dysfunction and by light chain isotype, making it the preferred partner to IFE. Validation of these results in a multicenter cohort is warranted.

Colon perforation in multiple myeloma patients - A complication of high-dose steroid treatment

Gastrointestinal complications of multiple myeloma (MM) treatment are common and include nausea, constipation, and diarrhea. However, acute gastrointestinal events like perforations are rare. We aimed to describe the characteristics and outcomes of patients with MM that had colonic perforations during their treatment. This is a retrospective study that included patients from all three Mayo Clinic sites who had MM and developed a colonic perforation. All patients were diagnosed with colonic perforations based on CT scans and were surgically treated. Patients diagnosed with AL amyloidosis, a perforated colon complicating neutropenic colitis during ASCT and those with perforation due to colonic cancer were excluded. A high dose of dexamethasone was defined as ≥40 mg dexamethasone once a week. Thirty patients met inclusion criteria. All patients received steroids at doses ≥10 mg once weekly prior to the perforation, while four (11%) were on high-dose dexamethasone without chemotherapy. Fourteen patients were given high doses of dexamethasone. Twenty-five patients required ostomies with all surviving surgery. Twenty-four perforations (80%) were associated with diverticulitis. Treatment with steroids was resumed in 23 patients with no further gastrointestinal complications. The median OS was 20 months following perforation (IQR 8-59). Within the same timeframe 5854 patients were treated at Mayo Clinic for MM, making the risk of bowel perforation 0.5%. Intestinal perforations in MM are rare and, in our series, always occurred with dexamethasone ≥10 mg per week. Urgent surgery is lifesaving and resumption of anti-myeloma treatment appears to be safe.

Correction: Bone marrow plasma cells 20% or greater discriminate presentation, response, and survival in AL amyloidosis

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Outcomes with early vs. deferred stem cell transplantation in light chain amyloidosis

In the presence of effective treatment options for systemic light chain (AL) amyloidosis, autologous stem cell transplantation (ASCT) is sometimes deferred after stem cell collection. We designed this retrospective study to compare overall survival (OS) between patients who proceed directly to ASCT after stem cell collection and those who defer ASCT. We included patients with AL amyloidosis who had stem cell collection at Mayo Clinic, Minnesota, from 2004 to 2018. ASCT was considered "early" if performed within 90 days of collection, and "deferred" if performed after 90 days, or not done by last follow up. We included 651 patients; 527 underwent early ASCT and 124 deferred ASCT. There was no difference in OS with early vs. deferred ASCT (median OS: 13.0 vs. 11.4 years, respectively, P = 0.28). There was no difference in OS between the 2 groups among patients with early or advanced Mayo Stage. Among patients who achieved ≥very good partial response at the time of collection, OS in the early and deferred groups was 14.2 and 13.4 years, respectively (P = 0.06). Survival outcomes are similar with early and deferred ASCT. Further studies are needed to identify patients who would benefit from each approach.

Impact of minimal residual negativity using next generation flow cytometry on outcomes in light chain amyloidosis

We evaluated bone marrow minimal residual disease (MRD) negativity in 44 patients with light chain (AL) amyloidosis using next generation flow cytometry (sensitivity ≥1 × 10-5 ; median events analyzed: 8.7 million, range: 4.8 to 9.7 million). All patients underwent MRD testing in 2 years from start of therapy (median: 7 months). The overall MRD negative rate was 64% (n = 28). The MRD-negative rate after one-line of therapy was 71% (20/28). And, MRD negative rates were higher with stem-cell transplant as first-line therapy (86%, 18/21) vs chemotherapy alone as first-line treatment (29%, 2/7), P = .005. The MRD negative rate amongst patients in complete response was 75% (15/20), and in very good partial response, 50% (11/22). There were two patients in partial response/rising light chains (with renal dysfunction) who were MRD negative. There were no differences in baseline characteristics of MRD negative vs MRD positive patients, except younger age amongst MRD-negative patients. Patients with MRD negativity were more likely to have achieved cardiac response at the time of MRD assessment, 67% (8/12) vs 22% (2/7), P = .04. Renal response rates were similar in both groups. Progression free survival was assessed in the 42 patients achieving CR or VGPR. After median follow-up of 14 months, the estimated 1-year progression free survival in MRD negative vs MRD positive patients was 100% (26 patients, 0 events) vs 64% (16 patients, five events), P = .006, respectively. MRD assessment should be explored as a surrogate endpoint in clinical trials and MRD risk-adapted trials may help optimize treatment in AL amyloidosis.

Impact of MYD88L265P mutation status on histological transformation of Waldenström Macroglobulinemia

Histological transformation in Waldenström macroglobulinemia (WM) is an uncommon complication, with limited data, particularly regarding the impact of MYD88 ^L265P mutation on transformation. We examined risk factors and outcomes associated with transformation in WM, highlighting the role of MYD88 ^L265P mutation. Patients with WM seen at Mayo Clinic, Rochester, USA and University Hospital of Reims, France, between 01/01/1996 and December 31, 2017 were included; 50 (4.3%) of 1147 patients transformed to a high-grade lymphoma, with median time-to-transformation of 4.5 (range 0-21) years in the transformed cohort. The MYD88 ^L265P mutation status was known in 435/1147 (38%) patients (406 with non-transformed WM and 29 patients in transformed cohort). On multivariate analysis, MYD88 ^WT status alone was an independent predictor of transformation (odds ratio, 7[95%CI: 2.1-23]; P = .003). Additionally, the MYD88 ^WT status was independently associated with shorter time-to-transformation (HR 7.9 [95%CI: 2.3-27; P = .001]), with a 5-year transformation rate of 16% for MYD88 ^WT vs 2.8% with MYD88 ^L265P mutated patients. Patients with transformation demonstrated a significant increase in risk of death compared to patients who did not transform (HR 5.075; 95%CI: 3.8-6.8; P < .001). In conclusion, the MYD88 ^WT status is an independent predictor of transformation and associated with a shorter time-to-transformation. Additionally, transformation conferred an inferior overall survival in patients with WM.

Survival impact of achieving minimal residual negativity by multi-parametric flow cytometry in AL amyloidosis

Response assessment in light chain (AL) amyloidosis is challenging given the low level of circulating free light chains usually seen. Multi-parametric flow cytometry (MFC) from a marrow aspirate was demonstrated to retain a prognostic significance in several recent studies. In this work, 82 AL patients who had MFC study at end of therapy were analysed based on whether clonal plasma cells were detected or not. Among patients who achieved deep response (i.e. very good partial response or complete response) to first-line therapy, lack of clonal marrow plasma cells as measured by MFC was associated with improved progression-free survival (PFS) compared to patients with residual clonal plasma cells (3-year PFS 88% vs. 46%, p = .003), particularly among patients who achieved a complete response (3-year PFS 100% vs. 33%, p = .001). Absence of clonal plasma cells by MFC compared with patients with detectable clonal plasma cells among deep responders was associated with lower level of involved light chain (involved free light chain (iFLC), median 1.1 vs. 1.7 mg/dL; p = .02) and higher frequency of renal response (100% vs. 68%; p = .005). Further studies are needed to determine if MFC should be incorporated into response criteria in AL amyloidosis.