Genomic evolution of ibrutinib-resistant clones in Waldenström macroglobulinaemia

Ibrutinib is highly active in Waldenström macroglobulinaemia (WM) patients, but disease progression can occur due to acquired mutations in BTK, the target of ibrutinib, or PLCG2, the protein downstream of BTK. However, not all resistant patients harbour these alterations. We have performed a whole-exome sequencing study to identify alternative molecular mechanisms that can drive ibrutinib resistance. Our findings include deletions on chromosomes 6q, including homozygous deletions, and 8p, which encompass key regulators of BTK, MYD88/NF-κB, and apoptotic signalling. Moreover, we have identified recurring mutations in ubiquitin ligases, innate immune signalling, and TLR/MYD88 pathway regulators in ibrutinib-resistant WM patients.

Genomic Landscape of Waldenström Macroglobulinemia and Its Impact on Treatment Strategies

Next-generation sequencing has revealed recurring somatic mutations in Waldenström macroglobulinemia (WM), including MYD88 (95%-97%), CXCR4 (30%-40%), ARID1A (17%), and CD79B (8%-15%). Deletions involving chromosome 6q are common in patients with mutated MYD88 and include genes that modulate NFKB, BCL2, Bruton tyrosine kinase (BTK), and apoptosis. Patients with wild-type MYD88 WM show an increased risk of transformation and death and exhibit many mutations found in diffuse large B-cell lymphoma. The discovery of MYD88 and CXCR4 mutations in WM has facilitated rational drug development, including the development of BTK and CXCR4 inhibitors. Responses to many agents commonly used to treat WM, including the BTK inhibitor ibrutinib, are affected by MYD88 and/or CXCR4 mutation status. The mutation status of both MYD88 and CXCR4 can be used for a precision-guided treatment approach to WM.

SYK is activated by mutated MYD88 and drives pro-survival signaling in MYD88 driven B-cell lymphomas

Activating MYD88 mutations promote pro-survival signaling through BTK and HCK, both targets of ibrutinib. Despite high response rates, complete responses to ibrutinib are lacking, and other MYD88 triggered pro-survival pathways may contribute to primary drug resistance. B-cell receptor (BCR) signaling has been observed in lymphomas driven by mutated MYD88, even without activating the BCR pathway mutations. We identified activated SYK (p-SYK), a component of BCR in complex with MYD88 in MYD88-mutated WM and ABC DLBCL lymphoma cells. Confocal microscopy confirmed co-localization of MYD88 with SYK in MYD88-mutated cells. Knockdown of MYD88 or use of a MYD88 signaling inhibitor abrogated SYK activation, while expression of mutated but not wild-type MYD88 amplified p-SYK in MYD88-mutated and wild-type lymphoma cells. Knockdown of SYK or use of inhibitors targeting SYK blocked p-STAT3 and p-AKT signaling in MYD88-mutated cells. Cell viability analysis showed that combining ibrutinib and SYK inhibitors triggered synthetic killing of MYD88-mutated lymphoma cells. Our findings extend the spectrum of mutated MYD88 pro-survival signaling to include SYK directed BCR cross talk in MYD88-mutated lymphomas. Targeting SYK in combination with ibrutinib produces synthetic lethality, providing a framework for the clinical investigation of ibrutinib with SYK inhibitors in MYD88-mutated lymphomas.

A matched case-control study comparing features, treatment and outcomes between patients with non-IgM lymphoplasmacytic lymphoma and Waldenström macroglobulinemia

Cases of non-IgM lymphoplasmacytic lymphoma (LPL) are rare. We performed a case-control study comparing features and outcomes of 31 non-IgM LPL cases and 93 Waldenström macroglobulinemia (WM) controls matched by age, sex, and year of diagnosis. Odds of MYD88 mutations were lower (odds ratio (OR) 0.22, p = .05), and median time to treatment was shorter in cases than in controls (4 vs. 32 months; p < .001). Odds of extramedullary disease were higher (OR 4.20, p = .01), while odds of neuropathy (OR 0.22, p = .25), and hyperviscosity (OR 0.26, p = .26) were lower in cases than in controls. Odds of using chemoimmunotherapy were higher (OR 2.62, p = .11) while odds of using proteasome inhibitors (OR 0.35, p = .15) and BTK inhibitors (OR 0.17, p = .21) were lower in cases than in controls. There were no differences in response and overall survival (OS) between cases and controls. Despite clinicopathological differences, response, and survival outcomes are similar between non-IgM LPL cases and WM controls.

Evolution of Therapy for Relapsed/Refractory Multiple Myeloma

With so many recent advances in relapsed/refractory multiple myeloma, keeping abreast with current treatment recommendations can be challenging. Novel immunomodulators, proteasome inhibitors, monoclonal antibodies, histone deacetylase inhibitors, and nuclear export inhibitors have all been added to the armamentarium, and the choice of which of these drugs or drug combinations to use depends on individual disease-related and patient-related factors, previous therapies, and treatment toxicities. At the NCCN 2019 Annual Congress: Hematologic Malignancies, Dr. Jorge J. Castillo provided an overview of the myriad treatments available for patients with relapsed/refractory multiple myeloma, as well as therapies on the horizon.

What is new in the treatment of Waldenstrom macroglobulinemia?

Waldenstrom macroglobulinemia (WM) is a rare type of non-Hodgkin lymphoma. The diagnosis of WM is established by the presence of lymphoplasmacytic lymphoma in the bone marrow or other organs, a monoclonal IgM paraproteinemia and the recurrent MYD88 L265P somatic mutation. Some patients with WM can be asymptomatic, in which case treatment is not indicated. However, most patients with WM will become symptomatic during the course of the disease, due to anemia, hyperviscosity, neuropathy, or other processes, necessitating therapy. Current treatment options for symptomatic WM patients include alkylating agents, proteasome inhibitors and anti-CD20 monoclonal antibodies. The approval of the oral Bruton tyrosine kinase (BTK) inhibitor ibrutinib alone and in combination with rituximab has expanded the treatment options for WM patients. The present Perspective would focus on exciting treatment strategies under development for WM patients, such as proteasome inhibitors (e.g., ixazomib), BTK inhibitors (e.g., acalabrutinib, zanubrutinib, vecabrutinib), BCL2 inhibitors (e.g., venetoclax), and anti-CXCR4 antibodies (e.g., ulocuplumab), among others. It is certainly an exciting time for WM therapy development with novel and promising treatment options in the horizon.

Hematogenous extramedullary relapse in multiple myeloma - a multicenter retrospective study in 127 patients

The current study assesses the characteristics and outcomes of multiple myeloma (MM) patients, treated with novel agents for hematogenous extramedullary (HEMM) relapse. Consecutive patients diagnosed with HEMM between 2010-2018 were included. Patients' characteristics at diagnosis and at HEMM presentation, response to treatment, survival and factors predicting survival were recorded and analyzed. A group of 127 patients, all diagnosed with HEMM by imaging (87.3%) and/or biopsy (79%), were included. Of those, 44% were initially diagnosed with ISS3, 57% presented with plasmacytomas, and 30% had high-risk cytogenetics. Median time to HEMM was 32 months. In multivariate analysis, ISS3 and bone plasmacytoma predicted shorter time to HEMM (P = .005 and P = .008, respectively). Upfront autograft was associated with longer time to HEMM (P = .002). At HEMM, 32% of patients had no BM plasmacytosis, 20% had non-secretory disease and 43% had light-chain disease. Multiple HEMM sites were reported in 52% of patients, mostly involving soft tissue, skin (29%), and pleura/lung (25%). First treatment for HEMM included proteasome inhibitors (50%), immunomodulatory drugs (IMiDs) (39%), monoclonal antibodies (10%), and chemotherapy (53%). Overall response rate (ORR) was 57%. IMiDs were associated with higher ORR (HR 2.2, 95% CI 1.02-4.7, P = .04). Median survival from HEMM was 6 months (CI 95% 4.8-7.2). Failure to achieve ≥VGPR was the only significant factor for worse OS in multivariate analyses (HR = 9.87, CI 95% 2.35 - 39, P = .001). In conclusion, HEMM occurs within 3 years of initial myeloma diagnosis and is associated with dismal outcome. The IMiDs might provide a higher response rate, and achievement of ≥VGPR predicts longer survival.

How we manage Bing-Neel syndrome

Bing-Neel syndrome (BNS) is an uncommon presentation of Waldenström macroglobulinaemia (WM), seen during the course of the disease in about 1% of patients. BNS occurs when WM cells gain access to the central nervous system (CNS) causing neurological deficits. The diagnosis of BNS is suggested by the presence of radiological abnormalities, such as leptomeningeal enhancement on magnetic resonance imaging and confirmed by the presence of clonal lymphoplasmacytic cells and MYD88 L265P in the cerebrospinal fluid. The treatment of BNS requires agents with good penetration into the CNS, such as fludarabine, methotrexate and cytarabine. The novel Bruton Tyrosine Kinase inhibitor ibrutinib has shown CNS-penetrating properties, and recent data suggest a therapeutic role in BNS. In this review, we will discuss the clinical and pathological features, diagnostic criteria, treatment options and outcomes of patients with BNS.

CXCR4 mutations affect presentation and outcomes in patients with Waldenström macroglobulinemia: A systematic review

Introduction: The genomic landscape of Waldenström macroglobulinemia (WM) is characterized by recurrent MYD88 (MYD88^L265P) and CXCR4 mutations (CXCR4^MUT), detected in 90% and 30% of cases, respectively. The role of CXCR4^MUT in clinical features and outcomes to therapy in WM patients is evolving. Areas covered: We performed a systematic review aimed at evaluating the prevalence of CXCR4^MUT in WM patients, and at assessing differences in clinical features and outcomes to therapy between WM patients with and without CXCR4^MUT. Seventeen studies were included in our analysis. The pooled prevalence of CXCR4^MUT in WM patients was 31%; 34% in MYD88^L265P and 5% in MYD88^WT patients. CXCR4^MUT were associated with higher serum IgM levels and higher risk of hyperviscosity than CXCR4^WT patients. Very good partial response (VGPR) and progression-free survival (PFS) rates to ibrutinib, with and without rituximab, appeared lower in CXCR4^MUT than in CXCR4^WT patients. Response and PFS rates were not affected by CXCR4^MUT status on patients treated with proteasome inhibitors. Expert opinion: Our systematic review shows that WM patients with CXCR4^MUT have specific clinical features and have lower response and PFS rates to BTK inhibitors. Our findings support standardization of CXCR4 testing and development of CXCR4-directed therapy.

High Red Cell Distribution Width is an Adverse Predictive and Prognostic Factor in Patients With Diffuse Large B-Cell Lymphoma Treated With Chemoimmunotherapy

INTRODUCTION

The red blood cell distribution width (RDW) is an easy-to-obtain laboratory value that has emerged as a potential prognostic factor in solid and hematologic malignancies.

PATIENTS AND METHODS

We evaluated 121 patients with de novo diffuse large B-cell lymphoma (DLBCL) treated with standard chemoimmunotherapy at our institution between 2010 and 2012. We categorized patients with high RDW (> 14.6%) and normal RDW (11.6%-14.6%). We fitted multivariate regression models for complete response (CR) and overall survival (OS).

RESULTS

Patients with high RDW were less likely to achieve CR to chemoimmunotherapy than patients with normal RDW (48% vs. 83%; P < .001). The 5-year OS rate for patients with high RDW was lower than in patients with normal RDW (51% vs. 79%; P = .001). In multivariate regression models, high RDW was independently associated with lower odds of achieving CR (odds ratio, 0.32; 95% confidence interval [CI], 0.12-0.83; P = .02) and with higher risk of death from any cause (hazard ratio [HR], 2.04; 95% CI, 1.03-4.02; P = .04) than normal RDW in patients with DLBCL treated with chemoimmunotherapy. High RDW remained an independent adverse factor for OS after adjustment for the International Prognostic Index and the National Comprehensive Cancer Network-International Prognostic Index scores with HR 2.20 (95% CI, 1.12-4.31; P = .02) and HR 2.67 (95% CI 1.28-5.59; P = .009), respectively.

CONCLUSION

High RDW appears to be an adverse predictive and prognostic factor in patients with de novo DLBCL treated with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone).

CXCR4 mutation subtypes impact response and survival outcomes in patients with Waldenström macroglobulinaemia treated with ibrutinib

Ibrutinib is associated with response rate of 90% and median progression-free survival (PFS) in excess of 5 years in Waldenström macroglobulinaemia (WM) patients. CXCR4 mutations are detected in 30-40% of patients with WM and associate with lower rates of response and shorter PFS to ibrutinib therapy. Both frameshift (CXCR4^FS ) and nonsense (CXCR4^NS ) CXCR4 mutations have been described. The impact of these mutations on outcomes to ibrutinib have not been evaluated in WM patients. We studied consecutive patients with a diagnosis of WM, on ibrutinib therapy, for the presence of CXCR4^FS and CXCR4^NS mutations and evaluated the differences in response and PFS between groups. Of 180 patients, 68 patients (38%) had CXCR4 mutations; 49 (27%) had CXCR4^NS and 19 (11%) had CXCR4^FS mutations. In multivariate models, patients with CXCR4^NS had lower odds of major response (Odds ratio 0·25, 95% confidence interval [CI] 0·12-0·53; P < 0·001) and worse PFS (Hazard ratio 4·02, 95% CI 1·95-8·26; P < 0·001) than patients without CXCR4 mutations. CXCR4^FS was not associated with worse major response or PFS rates than patients without CXCR4 mutations. Our results suggest different response and PFS rates to ibrutinib for WM patients with CXCR4^NS and CXCR4^FS , and advocate in favour of CXCR4 mutational testing as well as CXCR4-directed therapy.

Progression Risk Stratification of Asymptomatic Waldenström Macroglobulinemia

BACKGROUND

Waldenström macroglobulinemia (WM) is preceded by asymptomatic WM (AWM), for which the risk of progression to overt disease is not well defined.

METHODS

We studied 439 patients with AWM, who were diagnosed and observed at Dana-Farber Cancer Institute between 1992 and 2014.

RESULTS

During the 23-year study period, with a median follow-up of 7.8 years, 317 patients progressed to symptomatic WM (72%). Immunoglobulin M 4,500 mg/dL or greater, bone marrow lymphoplasmacytic infiltration 70% or greater, β2-microglobulin 4.0 mg/dL or greater, and albumin 3.5 g/dL or less were all identified as independent predictors of disease progression. To assess progression risk in patients with AWM, we trained and cross-validated a proportional hazards model using bone marrow infiltration, immunoglobulin M, albumin, and beta-2 microglobulin values as continuous measures. The model divided the cohort into three distinct risk groups: a high-risk group with a median time to progression (TTP) of 1.8 years, an intermediate-risk group with a median TTP of 4.8 years, and a low-risk group with a median TTP of 9.3 years. We validated this model in two external cohorts, demonstrating robustness and generalizability. For clinical applicability, we made the model available as a Web page application ( www.awmrisk.com ). By combining two cohorts, we were powered to identify wild type MYD88 as an independent predictor of progression (hazard ratio, 2.7).

CONCLUSION

This classification system is positioned to inform patient monitoring and care and, for the first time to our knowledge, to identify patients with high-risk AWM who may need closer follow-up or benefit from early intervention.

1130. Low Risk of Pneumocystis jiroveci Pneumonia in Patients With Waldenstrom’s Macroglobulinemia on Ibrutinib

Background

Ibrutinib is a Bruton’s tyrosine kinase inhibitor that is FDA approved for the treatment of chronic lymphocytic leukemia (CLL), mantle cell lymphoma, marginal zone lymphoma, and Waldenstrom’s macroglobulinemia (WM). Fungal infections including Pneumocystis jiroveci pneumonia (PCP) are increasingly reported in patients with CLL and lymphoma on ibrutinib possibly due to the off-target effect of ibrutinib on the adaptive immune system. Whether this increased risk is due to the effect of ibrutinib alone or in combination with immune dysregulation due to underlying malignancy is unknown. The purpose of this study was to assess the incidence of PCP in patients with WM on ibrutinib therapy.

Methods

A retrospective cohort study was performed of all patients with WM who initiated ibrutinib monotherapy at Dana-Farber Cancer Institute between July 1, 2015 and January 30, 2018. Baseline characteristics, laboratory parameters, previous and concomitant malignancy treatment regimens, and antimicrobial medications were collected by chart review. Patients were followed until April 1, 2018 for the development of PCP.

Results

There were a total of 106 patients with WM on ibrutinib during the study period. Sixty-one (58%) were male, and the median age at initiation of ibrutinib was 69 years (range 43 – 89). Forty-six patients (43%) received prior therapy for WM, with a median of two previous treatment courses (range 1–6). Fourteen patients (13%) were on PCP prophylaxis for a combined duration of 8 person-years. No cohort patient developed PCP during the study period, which included 146 person-years of ibrutinib exposure. Three patients (3%) died due to disease progression (n = 2) and E. coli sepsis (n = 1).

Conclusion

Patients with WM on ibrutinib monotherapy appear to have a different infectious risk profile than patients with CLL or lymphoma and do not have a high risk of developing PCP. These data suggest that PCP prophylaxis is likely not beneficial for patients with WM on ibrutinib.

Disclosures

M. P. Cheng, Royal College of Physicians and Surgeons of Canada: Member, Salary. S. P. Hammond, Merck: Investigator, Research support. J. J. Castillo, Pharmacyclics: Consultant and Grant Investigator, Consulting fee and Research grant. N. C. Issa, GSK: Investigator, Research grant. Merck: Investigator, Research grant. Akros Pharma: Consultant, Consulting fee.

Profiling of circulating exosomal miRNAs in patients with Waldenström Macroglobulinemia

Waldenström Macroglobulinemia (WM) is a low-grade B-cell lymphoma characterized by disease progression from IgM MGUS to asymptomatic and then symptomatic disease states. We profiled exosomes from the peripheral blood of patients with WM at different stages (30 smoldering/asymptomatic WM, 44 symptomatic WM samples and 10 healthy controls) to define their role as potential biomarkers of disease progression. In this study, we showed that circulating exosomes and their miRNA content represent unique markers of the tumor and its microenvironment. We observed similar levels of miRNAs in exosomes from patients with asymptomatic (smoldering) and symptomatic WM, suggesting that environmental and clonal changes occur in patients at early stages of disease progression before symptoms occur. Moreover, we identified a small group of miRNAs whose expression correlated directly or inversely with the disease status of patients, notably the known tumor suppressor miRNAs let-7d and the oncogene miR-21 as well as miR-192 and miR-320b. The study of these miRNAs’ specific effect in WM cells could help us gain further insights on the mechanisms underlying WM pathogenesis and reveal their potential as novel therapeutic targets for this disease.

Ibrutinib Monotherapy in Symptomatic, Treatment-Naïve Patients With Waldenström Macroglobulinemia

Purpose

Ibrutinib is active in previously treated Waldenström macroglobulinemia (WM). MYD88 mutations ( MYD88MUT) and CXCR4 mutations ( CXCR4MUT) affect ibrutinib response. We report on a prospective study of ibrutinib monotherapy in symptomatic, untreated patients with WM, and the effect of CXCR4MUT status on outcome.

Patients and Methods

Symptomatic, treatment-naïve patients with WM were eligible. Ibrutinib (420 mg) was administered daily until progression or unacceptable toxicity. All tumors were genotyped for MYD88MUT and CXCR4MUT.

Results

A total of 30 patients with WM received ibrutinib. All carried MYD88MUT, and 14 (47%) carried a CXCR4MUT. After ibrutinib treatment, median serum IgM levels declined from 4,370 to 1,513 mg/dL, bone marrow involvement declined from 65% to 20%, and hemoglobin level rose from 10.3 to 13.9 g/dL ( P < .001 for all comparisons). Overall (minor or more than minor) and major (partial or greater than partial) responses for all patients were 100% and 83%, respectively. Rates of major (94% v 71%) and very good partial (31 v 7%) responses were higher and time to major responses more rapid (1.8 v 7.3 months; P = 0.01) in patients with wild-type CXCR4 versus those with CXCR4MUT, respectively. With a median follow-up of 14.6 months, disease in two patients (both with CXCR4MUT) progressed. The 18-month, estimated progression-free survival is 92% (95% CI, 73% to 98%). All patients are alive. Grade 2/3 treatment-related toxicities in > 5% of patients included arthralgia (7%), bruising (7%), neutropenia (7%), upper respiratory tract infection (7%), urinary tract infection (7%), atrial fibrillation (10%), and hypertension (13%). There were no grade 4 or unexpected toxicities.

Conclusion

Ibrutinib is highly active, produces durable responses, and is safe as primary therapy in patients with symptomatic WM. CXCR4MUT status affects responses to ibrutinib.

Monoclonal Antibodies for Waldenström Macroglobulinemia

For the last 2 decades, anti-CD20 monoclonal antibodies have revolutionized the treatment of patients with B-cell lymphomas. These agents have shown efficacy when used as single agents and also have improved response and survival rates when added to chemotherapy. Monoclonal antibodies are safe and effective as well in patients with Waldenström macroglobulinemia (WM). The purpose of this article is to review the mechanism of action of monoclonal antibodies and to discuss current clinical data supporting their use in patients with WM. This review focuses on retrospective and prospective studies and clinical trials on anti-CD20 antibodies, anti-CD38 antibody, and anti-CXCR4 antibody.

TP53 mutations are associated with mutated MYD88 and CXCR4, and confer an adverse outcome in Waldenström macroglobulinaemia

Little is known about TP53 mutations in Waldenström Macroglobulinaemia (WM). We evaluated 265 WM patients for TP53 mutations by next-generation sequencing, and validated the findings by Sanger sequencing. TP53 mutations were identified and validated in 6 (2·6%) patients that impacted the DNA-binding domain. All six were MYD88- and CXCR4-mutated. Ibrutinib showed activity in patients carrying all three mutations. With a median follow-up of 18 months, 2 (33%) with biallelic TP53 inactivation died of progressive disease. TP53 mutations are rare in WM, and associate with MYD88 and CXCR4 mutations. WM patients with TP53 mutations show response to ibrutinib.

Ibrutinib discontinuation in Waldenström macroglobulinemia: Etiologies, outcomes, and IgM rebound

Ibrutinib is the first approved therapy for symptomatic patients with Waldenström macroglobulinemia (WM). The reasons for discontinuing ibrutinib and subsequent outcomes have not been previously evaluated in WM patients. We therefore conducted a retrospective review of 189 WM patients seen at our institution who received treatment with ibrutinib, of whom 51 (27%) have discontinued therapy. Reasons for discontinuation include: disease progression (n = 27; 14%), toxicity (n = 15; 8%), nonresponse (n = 5; 3%), and other unrelated reasons (n = 4; 2%). The cumulative incidence of ibrutinib discontinuation at 12, 24, 36, and 48 months from treatment initiation was 22%, 26%, 35%, and 43%, respectively. A baseline platelet count ≤100 K/µL and presence of tumor CXCR4 mutations were independently associated with 4-fold increased odds of ibrutinib discontinuation. An IgM rebound (≥25% increase in serum IgM) was observed in 37 patients (73%) following ibrutinib discontinuation and occurred within 4 weeks for nearly half of patients. The response rate to salvage therapy was 71%; responses were higher in patients without an IgM rebound and when salvage therapy was initiated within 2 weeks of stopping ibrutinib. Patients who discontinued ibrutinib due to disease progression versus nonprogression events had significantly shorter overall survival (21 versus 32 months; P = .046). Response to salvage therapy was associated with an 82% reduction in the risk of death following ibrutinib discontinuation. WM patients who discontinue ibrutinib require close monitoring, and continuation of ibrutinib until the next therapy should be considered to maintain disease control.

Initial Evaluation of the Patient with Waldenström Macroglobulinemia

The initial evaluation of the patient with Waldenström macroglobulinemia can be challenging. Not only is it a rare disease, but the clinical features can vary greatly from patient to patient. In this article, we aim at providing concise and practical recommendations for the initial evaluation of patients with Waldenström macroglobulinemia, specifically regarding history taking, physical examination, laboratory testing, bone marrow aspiration, and biopsy evaluation and imaging studies. We then review the most common special clinical situations seen in patients with Waldenström macroglobulinemia, especially anemia, hyperviscosity, cryoglobulinemia, peripheral neuropathy, extramedullary disease, Bing-Neel syndrome, and amyloidosis.

Multiple myeloma in patients up to 30 years of age: a multicenter retrospective study of 52 cases

A small proportion of patients with multiple myeloma (MM) are diagnosed at a very young age. The clinicopathological characteristics and prognosis of these patients are not well known. This analysis included 52 patients diagnosed with MM at the age of ≤30 years (range: 8-30 years). 68% of patients had International Scoring System (ISS) 1 MM; 22% presented with the light chain-only disease, and 48% with elevated serum lactate dehydrogenase (LDH). 85% of patients were treated with novel agents, and 62% received front-line autologous stem cell transplantation (ASCT). Overall response rate (ORR) to front-line treatment and ASCT were 71% and 90%, respectively. The group was followed-up for the median period of 86 months. The median overall survival (OS) was 166 months (95% CI: 53-222), with 5-year OS rate of 77% (95% CI: 61.0-87.9). This findings suggest that the prognosis in young MM patients may be as good if not better than in the general population of MM patients.

EBV-positive diffuse large B-cell lymphoma, not otherwise specified: 2018 update on diagnosis, risk-stratification and management

DISEASE OVERVIEW

Epstein Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) is an entity included in the 2016 WHO classification of lymphoid neoplasms. EBV+ DLBCL, NOS, is an aggressive B-cell lymphoma associated with chronic EBV infection, and a poor prognosis with standard chemotherapeutic approaches.

DIAGNOSIS

The diagnosis is made through a careful pathological evaluation. Detection of EBV-encoded RNA is considered standard for diagnosis; however, a clear cutoff for positivity has not been defined. The differential diagnosis includes plasmablastic lymphoma, DLBCL associated with chronic inflammation, primary effusion lymphoma, HHV8+ DLBCL, NOS, and EBV+ mucocutaneuos ulcer.

RISK-STRATIFICATION

The International prognostic index (IPI) and the Oyama score can be used for risk-stratification. The Oyama score includes age >70 years and presence of B symptoms. The expression of CD30 is emerging as a potential adverse, and targetable, prognostic factor.

MANAGEMENT

Patients with EBV+ DLBCL, NOS, should be staged and managed following similar guidelines than patients with EBV-negative DLBCL. EBV+ DLBCL, NOS, however, has a worse prognosis than EBV-negative DLBCL in the era of chemoimmunotherapy. There is an opportunity to study and develop targeted therapy in the management of patients with EBV+ DLBCL, NOS.

Prognostic indicators in primary plasma cell leukaemia: a multicentre retrospective study of 117 patients

We report a multicentre retrospective study that analysed clinical characteristics and outcomes in 117 patients with primary plasma cell leukaemia (pPCL) treated at the participating institutions between January 2006 and December 2016. The median age at the time of pPCL diagnosis was 61 years. Ninety-eight patients were treated with novel agents, with an overall response rate of 78%. Fifty-five patients (64%) patients underwent upfront autologous stem cell transplantation (ASCT). The median follow-up time was 50 months (95% confidence interval [CI] 33; 76), with a median overall survival (OS) for the entire group of 23 months (95% CI 15; 34). The median OS time in patients who underwent upfront ASCT was 35 months (95% CI 24·3; 46) as compared to 13 months (95% CI 6·3; 35·8) in patients who did not receive ASCT (P = 0·001). Multivariate analyses identified age ≥60 years, platelet count ≤100 × 10⁹ /l and peripheral blood plasma cell count ≥20 × 10⁹ /l as independent predictors of worse survival. The median OS in patients with 0, 1 or 2-3 of these risk factors was 46, 27 and 12 months, respectively (P < 0·001). Our findings support the use of novel agents and ASCT as frontline treatment in patients with pPCL. The constructed prognostic score should be independently validated.