Citations

Abstract Waldenström macroglobulinemia (WM) is a distinct B-cell lymphoproliferative disorder for which clearly defined criteria for the diagnosis, initiation of therapy, and treatment strategy have been proposed as part of the consensus panels of the International Workshop on Waldenström’s Macroglobulinemia (IWWM). At IWWM-8, a task force for treatment recommendations was impanelled to review recently published and ongoing clinical trial data as well as the impact of new mutations (MYD88 and CXCR4) on treatment decisions, indications for B-cell receptor and proteasome inhibitors, and future clinical trial initiatives for WM patients. The panel concluded that therapeutic strategies in WM should be based on individual patient and disease characteristics. Chemoimmunotherapy combinations with rituximab and cyclophosphamide-dexamethasone, bendamustine, or bortezomib-dexamethasone provide durable responses and are still indicated in most patients. Approval of the BTK inhibitor ibrutinib in the United States and Europe represents a novel and effective treatment option for both treatment-naive and relapsing patients. Other B-cell receptor inhibitors, second-generation proteasome inhibitors (eg, carfilzomib), and mammalian target of rapamycin inhibitors are promising and may increase future treatment options. Active enrollment in clinical trials whenever possible was endorsed by the panel for most patients with WM.

ObjectiveTo systematically compare transthyretin with primary amyloid neuropathy to define their natural history and the underlying mechanisms for differences in phenotype and natural history.MethodsAll patients with defined amyloid subtype and peripheral neuropathy who completed autonomic testing and electromyography at Mayo Clinic Rochester between 1993 and 2013 were included. Medical records were reviewed for time of onset of defined clinical features. The degree of autonomic impairment was quantified using the composite autonomic severity scale. Comparisons were made between acquired and inherited forms of amyloidosis.ResultsOne hundred one cases of amyloidosis with peripheral neuropathy were identified, 60 primary and 41 transthyretin. Twenty transthyretin cases were found to have Val30Met mutations; 21 had other mutations. Compared to primary cases, transthyretin cases had longer survival, longer time to diagnosis, higher composite autonomic severity scale scores, greater reduction of upper limb nerve conduction study amplitudes, more frequent occurrence of weakness, and later non‐neuronal systemic involvement. Four systemic markers (cardiac involvement by echocardiogram, weight loss > 10 pounds, orthostatic intolerance, fatigue) in combination were highly predictive of poor survival in both groups.InterpretationThese findings suggest that transthyretin has earlier and greater predilection for neural involvement and more delayed systemic involvement. The degree and rate of systemic involvement is most closely related to prognosis. Ann Neurol 2016;80:401–411

There is no consensus on whether patients with immunoglobulin light chain amyloidosis (AL) should receive induction therapy prior to an autologous stem cell transplant (ASCT). This study investigated the relationships between baseline bone marrow plasmacytosis (BMPC), cardiac staging, and pre‐transplant induction in AL patients. All patients who received ASCT for AL within 12 months of diagnosis were included. Patient characteristics and outcomes were abstracted. Univariate and multivariate modeling was performed. Among 415 AL patients, 35% had induction prior to ASCT. Post‐ASCT hematologic CR plus VGPR rates were significantly higher in those with baseline BMPC ≤ 10% compared to BMPC >10% (58% versus 40%, P = 0.0013). Significant risk factors for lack of attainment of CR included attenuated dose melphalan conditioning, baseline BMPC > 10%, no induction, and male gender. The 5‐year OS for the entire group was 65%. On multivariate analysis, risk factors for inferior OS included no induction therapy, advanced AL amyloid staging, BMPC > 10%, attenuated conditioning melphalan dose, and male gender. Patients with Mayo 2012 stage I–II patients with BMPC ≤ 10%, who comprised 56% of the ASCT population fared exceedingly well regardless of whether or not they received induction therapy with a 5‐year OS of 81 to 83%. Induction therapy pre‐ASCT may improve outcomes among AL patients due to a rapid reduction of toxic light chains or alternatively by elimination of less fit patients by “testing” their ability to tolerate chemotherapy. Prospective studies will be required to sort out these and other questions. Am. J. Hematol. 91:984–988, 2016. © 2016 Wiley Periodicals, Inc.

Amyloidosis is characterized by extracellular deposition of misfolded proteins as insoluble fibrils. Most renal amyloidosis cases are Ig light chain, AA, or leukocyte chemotactic factor 2 amyloidosis, but rare hereditary forms can also involve the kidneys. Here, we describe the case of a 61-year-old woman who presented with nephrotic syndrome and renal impairment. Examination of the renal biopsy specimen revealed amyloidosis with predominant involvement of glomeruli and medullary interstitium. Proteomic analysis of Congo red–positive deposits detected large amounts of the Apo-CII protein. DNA sequencing of the APOC2 gene in the patient and one of her children detected a heterozygous c.206A→T transition, causing an E69V missense mutation. We also detected the mutant peptide in the proband’s renal amyloid deposits. Using proteomics, we identified seven additional elderly patients with Apo-CII–rich amyloid deposits, all of whom had kidney involvement and histologically exhibited nodular glomerular involvement. Although prior in vitro studies have shown that Apo-CII can form amyloid fibrils and that certain mutations in this protein promote amyloid fibrillogenesis, there are no reports of this type of amyloidosis in humans. We propose that this study reveals a new form of hereditary amyloidosis (AApoCII) that is derived from the Apo-CII protein and appears to manifest in the elderly and preferentially affect the kidneys.

BACKGROUNDAutologous stem cell transplantation (SCT) is a common management strategy for select patients with immunoglobulin light‐chain amyloidosis, but no trials have documented improved overall survival.METHODSEighty‐nine patients with biopsy‐proven immunoglobulin light‐chain amyloidosis were allowed to select treatment with melphalan plus dexamethasone (n = 34) or SCT (n = 55); all patients were transplant eligible. Treatment preference resulted in imbalanced study arms. Patients who selected SCT were younger, more frequently had an Eastern Cooperative Oncology Group performance status score less than 2, had lower‐stage amyloidosis, and had a lower incidence of cardiac amyloidosis.RESULTSPatients receiving melphalan plus dexamethasone had a 3‐year progression‐free survival rate of 29.1% and an overall survival rate of 58.8%. Patients undergoing SCT had a 3‐year progression‐free survival rate of 51.7% and an overall survival rate of 83.6%. An attempt to match patients between the 2 arms in terms of risk produced 24 matched triplet sets (2 SCT patients for each melphalan‐dexamethasone patient); there was no difference in hematologic response, but there was better survival after autologous SCT. A propensity score–matched analysis of the cohorts (melphalan plus dexamethasone vs SCT) showed an overall mortality hazard ratio of 2.56 (P < .01).CONCLUSIONSAlthough the study had limitations, similar hematologic responses and improved survival were observed after SCT versus melphalan plus dexamethasone. Cancer 2016;122:2197–205. © 2016 American Cancer Society.

Over the past decade, a number of changes have occurred in the diagnostic evaluation, management, and long‐term follow‐up of patients with POEMS syndrome at our institution. This study included 291 patients with POEMS syndrome diagnosed at the Mayo Clinic between 1974 and 2014. Patients diagnosed after 2003 had more features of the syndrome identified at diagnosis and were more likely to receive an autologous transplant (49% versus 8%, P < 0.0001) and to have achieved a hematologic complete response (CR) to treatment (41% vs 25%, P < 0.0001). With 2273 person‐years of follow‐up, 10‐year overall survival (OS) was 62% (95% C.I., 56%, 67%). On multivariate analysis, the three factors associated with superior OS were younger age (RR 0.98 [0.96–1.00]), albumin greater‐than 3.2 g/dL (RR 0.5 [0.32–0.89]) and attainment of complete hematologic response (RR 0.4 [0.2, 0.9]). This study confirms the very good long‐term outcomes of patients with POEMS syndrome and identifies two new prognostic risk factors: albumin at diagnosis and attainment of complete hematologic response. Am. J. Hematol. 91:585–589, 2016. © 2016 Wiley Periodicals, Inc.