Italian Society of Hematology, Italian Society of Experimental Hematology, and Italian Group for Bone Marrow Transplantation Guidelines for the Management of Indolent, Nonfollicular B-Cell Lymphoma (Marginal Zone, Lymphoplasmacytic, and Small Lymphocytic Lymphoma)

Optimal Rituximab Monotherapy in Splenic Marginal Zone Lymphoma (SMZL): A Case Report and Brief Review

INTRODUCTION

Splenic marginal zone Lymphoma (SMZL) is a rare, chronic B lymphocyte proliferative disease. Generally, SMZL is accompanied by circulating atypical villous lymphocytes, known as SMZL with villous lymphocytes. Rituximab is a chimeric monoclonal antibody to CD20; recent but limited studies have confirmed its effectiveness in treating SMZL. Given the low incidence and selection of treatment, statistical comparisons of rituximab monotherapy with other available treatment options with the full range of data from previous clinical studies remain sparse. Here, we report a case of SMZL with villous lymphocytes treated by rituximab monotherapy, which is especially infrequently reported.

CASE REPORT

A 63-year-old Chinese female was presented to the hospital with complaints of splenomegaly and pain in the spleen area. Immunohistochemistry analysis was positive for IGH, IGK, and IGL clonal rearrangement. Villous lymphocytes were found in peripheral blood and bone marrow, along with further immunotyping results. The case was considered as SMZL with villous lymphocytes. Based on the SMZLSG prognosis assessment, we applied rituximab monotherapy. After eight cycles of rituximab treatment, the patient's condition improved markedly, with blood constituent and size of the spleen returning to normal levels, achieving complete response, with no significant side effect observed.

DISCUSSION

The patient provides a typical SMZL with villous lymphocytes case treated with rituximab monotherapy. Currently, the main treatment options include splenectomy and rituximab. After synthesizing a series of current views, we put forward our opinion about the selection of therapy for SMZL patients in order to gain maximum benefits for patients in need of treatment.

CONCLUSION

Our analysis found no statistically significant difference between rituximab monotherapy and rituximab combined with chemotherapy, while rituximab treatments resulted in better therapeutic effects than chemotherapy. Rituximab monotherapy has favorable therapeutic effects and minor adverse effects (AEs) in treating SMZL.

Splenic Marginal Zone Lymphoma in a Patient With Antiphospholipid Syndrome Treated With Rituximab: A Case Report

Splenic marginal zone lymphoma (SMZL) usually presents with splenomegaly or symptoms related to cytopenia. We report a case of a 56-year-old female with previously diagnosed antiphospholipid syndrome (APS) on warfarin therapy who initially presented with abdominal pain and was found to have massive splenomegaly and splenic infarction on CT imaging. Initial clinical presentations and imaging findings were attributed to the subtherapeutic coagulation profile. The patient was later diagnosed with SMZL following workup for pancytopenia including bone marrow biopsy, flow cytometry, and PET scan. Cytopenias, splenomegaly, and abnormal metabolic activity in the spleen on the PET scan improved after treatment with four cycles of weekly rituximab. Our report presents a case of a patient with longstanding APS presenting with splenic infarction and pancytopenia who was subsequently diagnosed with SMZL and successfully treated with rituximab.

Time Trend Analysis of Splenectomy for Splenic Marginal Zone Lymphoma: Declining Surgery, Promising Survival

BACKGROUND

The purpose of current study was to examine the incidence, characteristics, treatment, and survival of splenic marginal zone lymphoma (SMZL).

METHODS

Using SEER-18 database, patients diagnosed with SMZL between 2000 and 2018 were included. Effect of splenectomy on survival was evaluated after balancing the confounding factors by propensity score matching. Rates of splenectomy and 1-year relative survival were calculated for each year. A logistic regression model identified factors related to splenectomy, and a Cox regression model assessed factors linked to overall survival (OS).

RESULTS

A total of 2790 patients with SMZL were analyzed. The majority were older than 60 years, female, and white. The age-adjusted incidence of SMZL was 0.17/100,000 person-years, with higher incidence in males. Incidence increased by 0.68%/year and peaked at 80-84 years for both genders. The SMZL-specific survival rates at 3 and 5 years were 89.6% and 85.3%, respectively. Meanwhile, the relative survival rates for the same periods were 88.6% and 85.9%, respectively. Splenectomy patients were more likely to be younger, male, and diagnosed with early-stage disease. Despite the decreasing utilization rate of splenectomy from 59.4% in 2000 to 16.2% in 2018, the 1-year relative survival rate remained relatively stable with minor fluctuations over time. Whether or not the patient underwent splenectomy was not found to be a significant prognostic indicator for OS.

CONCLUSIONS

Our study demonstrated a decreasing use of splenectomy but a relatively stable survival in patients with SMZL, highlighting the urgency to better understand the role of splenectomy and its associated outcomes.

Identification of Six Diagnostic Biomarkers for Chronic Lymphocytic Leukemia Based on Machine Learning Algorithms

BACKGROUND

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in adults. Thus, novel reliable biomarkers need to be further explored to increase diagnostic, therapeutic, and prognostic effectiveness.

METHODS

Six datasets containing CLL and control samples were downloaded from the Gene Expression Omnibus database. Differential gene expression analysis, weighted gene coexpression network analysis (WGCNA), and the least absolute shrinkage and selection operator (LASSO) regression were applied to identify potential diagnostic biomarkers for CLL using R software. The diagnostic performance of the hub genes was then measured by the receiver operating characteristic (ROC) curve analysis. Functional analysis was implemented to uncover the underlying mechanisms. Additionally, correlation analysis was performed to assess the relationship between the hub genes and immunity characteristics.

RESULTS

A total number of 47 differentially expressed genes (DEGs) and 25 candidate hub genes were extracted through differential gene expression analysis and WGCNA, respectively. Based on the 14 overlapped genes between the DEGs and the candidate hub genes, LASSO regression analysis was used, which identified a final number of six hub genes as potential biomarkers for CLL: ABCA6, CCDC88A, PMEPA1, EBF1, FILIP1L, and TEAD2. The ROC curves of the six genes showed reliable predictive ability in the training and validation cohorts, with all area under the curve (AUC) values over 0.80. Functional analysis revealed an abnormal immune status in the CLL patients. A significant correlation was found between the hub genes and the immune-related pathways, indicating a possible tight connection between the hub genes and tumor immunity in CLL.

CONCLUSION

This study was based on machine learning algorithms, and we identified six genes that could be possible CLL markers, which may be involved in CLL pathogenesis and progression through immune-related signal pathways.

The Diagnostic Dilemma of Splenic Non-Hodgkin's Lymphoma and Splenic Abscess: A Narrative Review

Non-Hodgkin's lymphoma (NHL) is a lymphoproliferative disorder that principally displays lymph node involvement but can also spread to extranodal sites such as the spleen. Primary splenic NHL arises in the spleen and, due to its atypical presentation, can sometimes present similarly to other splenic conditions. This review aims to highlight how primary splenic NHL can be effectively differentiated from other splenic conditions, such as splenic abscesses. PubMed, MEDLINE, Scopus, Google, and Google Scholar were used to identify articles mainly focused on splenic non-Hodgkin's lymphoma and splenic abscess. The search was limited to articles published from January 2005 to November 2022. Of the 229 total articles amassed, only 34 were selected and narratively reviewed. From a thorough review of the current literature, it is evident that splenic NHL displays a similar clinical picture to other splenic conditions, namely splenic abscesses. One cannot easily differentiate between the two conditions, both clinically and via diagnostic imaging. Lymphadenopathy, a hallmark sign of nodal NHL, may or may not be present in splenic NHL. Ultimately, splenectomy with biopsy and immunohistochemical staining (IHC) may be required to confirm the diagnosis. In cases of suspected splenic NHL or splenic abscess with little-to-no symptomatic improvement after medication administration, splenectomy followed by histopathological examination may be required for a definitive diagnosis and proper treatment.

Refractory Splenic Marginal Zone Lymphoma Responsive to Combination Venetoclax and Bortezomib (Velcade) (V2) Therapy

Standard treatment regimens for the management of patients with refractory splenic marginal zone lymphoma (SMZL) are currently unavailable. Here, we report a case of SMZL, which, after failing multiple therapeutics, demonstrated an impressive clinical response to combined Venetoclax and Velcade (V²), a treatment combination currently being investigated in the setting of refractory multiple myeloma. We also report a unique histopathology and mutational profile that may have important implications for the characterization and prognosis of SMZL.

Sulfur Exafluoride Contrast-Enhanced Ultrasound Showing Early Wash-Out of Marked Degree Identifies Lymphoma Invasion of Spleen with Excellent Diagnostic Accuracy: A Monocentric Study of 260 Splenic Nodules

Contrast-enhanced ultrasonography (CEUS) use for detecting lymphoma in the spleen was questioned because of the risk of its inadequate diagnostic accuracy. The aim of the present study was to validate CEUS exam for the identification of spleen involvement by lymphoma in patients at risk. A total of 260 nodules from the spleens of 77 patients with lymph node biopsy-proven non-Hodgkin lymphoma (NHL; n = 44) or Hodgkin lymphoma (HL; n = 33) at staging (n = 56) or follow-up (n = 21) were collected in a hematology Italian center and retrospectively analyzed. Nodules were classified as malignant lymphoma if ≥0.5 cm (long axis) with arterial phase isoen-hancement and early (onset <60 s after contrast agent injection) wash-out of marked (≤120 s after contrast agent injection) degree. Other perfusional combinations at CEUS scans qualified lesions as benign or inconclusive. Diagnostic reference standard was clinical laboratory imaging monitoring for 230 nodules, and/or histology for 30 nodules. The median nodule size was 1.5 cm (range 0.5−7 cm). According to the reference standard, 204 (78%) nodules were lymphomas (aggressive-NHL (a-NHL), 122; classic-HL (c-HL), 65; indolent (i)-NHL, 17) and 56 (22%) were benign (inflammation, infection, and/or mesenchymal) lesions. Sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy of CEUS for detecting lymphoma in the spleen were 95%, 100%, 100%, 85%, and 96%, respectively. Marked wash-out range of 55−90 s (median, 74 s), 92−120 s (median, 100 s), and 101−120 s (median, 114.5 s) was 100%, 96.6%, and 77% predictive of a-NHL, c-HL, and i-NHL splenic nodular infiltration, respectively. The CEUS perfusional pattern of arterial phase isoenhancement with early wash-out of marked degree was highly accurate for the detection of lymphomatous invasion of spleen in patients at risk, enabling its use for a confident non-invasive diagnosis.

Clinical Characteristics, Treatment and Evolution of Splenic and Nodal Marginal Zone Lymphomas-Retrospective and Multicentric Analysis of Portuguese Centers

INTRODUCTION

Treatment of Splenic (SMZL) and Nodal (NMZL) Marginal Zone Lymphoma is not consensual. Histologic transformation (HT) to aggressive lymphoma is a poorly understood event, with an unfavorable outcome.

OBJECTIVES

Describe the clinical characteristics, treatment, outcomes and incidence of HT.

METHODS

Characteristics of patients with SMZL and NMZL consecutively diagnosed in 8 Portuguese centers were retrospectively reviewed. Endpoints were overall survival (OS), time to first systemic treatment (TTFST), frequency of HT and time to transformation (TTT).

RESULTS

This study included 122 SMZL and 68 NMZL, most of them received systemic treatment: 55.4% and 76.5%, respectively. Splenectomy was performed in 58.7% of patients with SMZL. Different treatment protocols were used. OS or TTFST did not differ significantly according to treatments. Given the small sample size, no conclusion can be made concerning the role of Rituximab in the treatment of NMZL and SMZL based in these results. HT was documented in 18 patients, mainly in SMZL, with a cumulative incidence at 5 years of 4.2%. We confirmed that age is a prognostic factor.

CONCLUSION

Randomized prospective trials are needed to standardize treatment in MZL. Patients with HT did appear to have shorter OS in comparison with those who did not experience HT (OS 5 years of 68.4% vs. 80.4%), but the number of HT was too small to reach statistical significance.

Rituximab Monotherapy or in Combination with Bendamustine Is Not Inferior to Rituximab-CHOP Regimen in the Treatment of Patients with Splenic Marginal Zone Lymphoma in the Real Life

Splenic marginal zone lymphoma (SMZL) is a rare lymphoma belonging to the marginal zone lymphoproliferative disorders. Usually, SMZL occurs with indolent presentation and, when required, the standard of care is represented by rituximab-based regimens. No direct comparison of different rituximab-based combinations and polychemotherapy regimens has been conducted to date. In a monocentric cohort of 68 SMLZ patients, we showed that rituximab in monotherapy or in combination with bendamustine, compared with rituximab associated with the polychemotherapy cycle cyclophosphamide, hydroxydaunorubicin, vincristine and prednisolone (CHOP), resulted in a higher 5-year progression-free survival (91.3 ± 9% and 75 ± 15.7% vs. 30.8 ± 12.1%, p < 0.001). Platelets at diagnosis <100 ×109/L (p = 0.034, HR = 4.3) and transformation into diffuse large B-cell lymphoma (p = 0.031, HR = 4.3) were associated with a lower overall survival.

EULAR recommendations for the management of Sjögren's syndrome with topical and systemic therapies

The therapeutic management of Sjögren syndrome (SjS) has not changed substantially in recent decades: treatment decisions remain challenging in clinical practice, without a specific therapeutic target beyond the relief of symptoms as the most important goal. In view of this scenario, the European League Against Rheumatism (EULAR) promoted and supported an international collaborative study (EULAR SS Task Force) aimed at developing the first EULAR evidence and consensus-based recommendations for the management of patients with SjS with topical and systemic medications. The aim was to develop a rational therapeutic approach to SjS patients useful for healthcare professionals, physicians undergoing specialist training, medical students, the pharmaceutical industry and drug regulatory organisations following the 2014 EULAR standardised operating procedures. The Task Force (TF) included specialists in rheumatology, internal medicine, oral health, ophthalmology, gynaecology, dermatology and epidemiology, statisticians, general practitioners, nurses and patient representatives from 30 countries of the 5 continents. Evidence was collected from studies including primary SjS patients fulfilling the 2002/2016 criteria; when no evidence was available, evidence from studies including associated SjS or patients fulfilling previous sets of criteria was considered and extrapolated. The TF endorsed the presentation of general principles for the management of patients with SjS as three overarching, general consensus-based recommendations and 12 specific recommendations that form a logical sequence, starting with the management of the central triplet of symptoms (dryness, fatigue and pain) followed by the management of systemic disease. The recommendations address the use of topical oral (saliva substitutes) and ocular (artificial tear drops, topical non-steroidal anti-inflammatory drugs, topical corticosteroids, topical CyA, serum tear drops) therapies, oral muscarinic agonists (pilocarpine, cevimeline), hydroxychloroquine, oral glucocorticoids, synthetic immunosuppressive agents (cyclophosphamide, azathioprine, methotrexate, leflunomide and mycophenolate), and biological therapies (rituximab, abatacept and belimumab). For each recommendation, levels of evidence (mostly modest) and TF agreement (mostly very high) are provided. The 2019 EULAR recommendations are based on the evidence collected in the last 16 years in the management of primary 2002 SjS patients and on discussions between a large and broadly international TF. The recommendations synthesise current thinking on SjS treatment in a set of overarching principles and recommendations. We hope that the current recommendations will be broadly applied in clinical practice and/or serve as a template for national societies to develop local recommendations.

Splenic marginal zone lymphoma treated with laparoscopic splenectomy: A case report

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The authors present a case of splenic marginal zone lymphoma (SMZL), which was successfully treated with laparoscopic splenectomy.

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SMZL is a rare subtype of indolent B cell lymphoma, and good prognosis is expected by splenectomy alone.

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Laparoscopic splenectomy is safe and feasible with splenic artery embolization preoperatively, especially in cases with large splenomegaly as seen in our case.

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Careful postoperative follow-up is required since some patients develop aggressive transformation, and result in worse prognosis.

Introduction

Splenic marginal zone lymphoma (SMZL) is rare subtype of malignant lymphoma that is classified as a low-grade B cell lymphoma. Splenectomy is usually chosen for both diagnosis and treatment, which often leads to the resolution of abdominal symptoms and cytopenia.

Case presentation

We presented the case of a 73-year-old woman who complained of spontaneous perspiration and fatigue. She was referred to our hospital for further treatment of enlarged intraabdominal lymph nodes and splenomegaly. The level of soluble Interleukin-2 receptor was elevated, and malignant lymphoma was suspected. Endoscopic ultrasound fine-needle biopsy of intraabdominal lymph node revealed B cell lymphoma. For a definitive diagnosis, as well as treatment, laparoscopic splenectomy was successfully performed. The histopathological finding was compatible with SMZL. The patient was discharged without any complications and observed to have no recurrence at eight months postoperatively.

Conclusion

Patients with SMZL is usually expected to have good prognosis with splenectomy. However, careful follow-up is required for aggressive transformation can occur and result in worse prognosis.

AISF position paper on HCV in immunocompromised patients

This report summarizes the clinical features and the indications for treating HCV infection in immunocompromised and transplanted patients in the Direct Acting Antiviral drugs era.

Study of gene polymorphisms as predictors of treatment efficacy and toxicity in patients with indolent non-hodgkin lymphomas and mantle cell lymphoma receiving bendamustine and rituximab

Bendamustine is used in combination with rituximab (BR) to treat indolent non-Hodgkin lymphomas (iNHL) and mantle cell lymphoma (MCL). The variability in treatment efficacy and toxicity could be related to single nucleotide polymorphisms (SNPs) in immune response genes. We would like to show a correlation between SNPs and treatment outcome in iNHL and MCL patients receiving BR. We investigated some SNPs that had already been associated with NHL outcome. Samples were genotyped for the IL2 (rs2069762), IL10 (rs1800890, rs10494879), VEGFA (rs3025039), IL8 (rs4073), CFH (rs1065489) and MTHFR (rs1801131) SNPs by allelic discrimination assays. We enrolled 70 patients that received rituximab 375 mg/m² and bendamustine 90 mg/m² every 28 days, both as first-line treatment and ≥ second-line regimens. Overall response rate was 97·1% (complete response [CR] rate 73·9%). Treatment toxicity included grade 3-4 neutropenia (24/70 patients), infections (21/70 patients; 1/70 grade 3), skin rash (26/70 patients; 2/70 grade 3). After a median follow-up of 24 months we did find any correlation between the analysed SNPs, CR rate and PFS. However, we demonstrated an association between the SNP in IL2 (rs2069762) and the onset of skin rash (P = 0·0001). Our study suggests a role for cytokine SNPs in bendamustine-related toxicity, which could represent a promising research field.

Management of relapsed/refractory marginal zone lymphoma: focus on ibrutinib

Marginal zone lymphomas (MZLs) consist of a diverse family of malignancies, which are derived from B-cells. The disease subtypes are recognized extranodal, nodal, and splenic MZLs. The disease characteristics, clinical course, and treatment vary considerably based on the site of involvement. In 2017, the US Food and Drug Administration approved ibrutinib, a first in class Bruton’s tyrosine kinase inhibitor that revolutionized the care of chronic lymphocytic leukemia patients; for, the treatment of relapsed/refractory MZL based on pivotal open-label Phase II trial demonstrated an overall response rate of 48%, with a complete response rate of 3%, median progression-free survival of 14.2 months, and median overall survival not yet reached at a median follow-up of 19.4 months. In this review, we aim to summarize the current conundrums in the management of MZL and the evolving role of ibrutinib in the treatment of MZL.

Long-term efficacy and toxicity of rituximab plus fludarabine and mitoxantrone (R-FM) for gastric marginal zone lymphoma: a single-center experience and literature review

There is no consensus about the best treatment option for patients with HP-negative gastric MALT lymphomas or persistent disease after HP eradication.We have investigated fludarabine and mitoxantrone with rituximab (R-FM) as first-line treatment. A cohort of 13 patients was analyzed. Induction treatment consisted of fludarabine (25 mg/m² i.v. on days 2 to 4), mitoxantrone (10 mg/m² i.v. on day 2), and rituximab (375 mg/m² i.v. on day 1), for up to six cycles every 28 days. All patients achieved a complete remission, a median of four cycles was given. Treatment-related toxicities were mainly hematologic, with grade 3-4 neutropenia observed in 11/13 patients (84.6%). One patient had grade 3 febrile neutropenia, two patients developed prolonged pancytopenia (15%), and one patient experienced CMV reactivation at 2 months. After a median follow-up of 84 months, 1/13 had disease relapse and received total gastrectomy; estimated 10-year progression-free survival and overall survival were 92.4 and 100%, respectively. Our study suggests R-FM regimen has a high long-term efficacy for untreated HP-negative gastric MALT lymphoma patients and HP-positive patients who failed HP eradication. The elevated incidence of grade 3-4 hematological toxicity, yet manageable, makes this treatment less safe compared to rituximab in combination with chlorambucil or bendamustine.

Overview on the management of non-gastric MALT lymphomas

Extranodal marginal zone B-cell lymphomas (EMZLs) of the mucosa-associated lymphoid tissue (MALT) are indolent lymphomas which can present at any extranodal site. The most frequent localizations (other than stomach) are ocular adnexa, salivary gland, skin, lung and thyroid. Chronic inflammation and antigenic stimulation are a potential risk for the development of MALT lymphomas. While Helicobacter Pylori (HP) is known to be associated with gastric MALT lymphoma and antibiotic therapy is effective in the setting of HP-positive, other microorganisms (such as Chlamydophila Psittaci, Campylobacter Jejiuni, Borrelia Burgdoferi) have been implicated in the pathogenesis of non-gastric MALT lymphomas. However, antibiotic therapy has not been extensively investigated for the non-gastric type, except for ocular adnexal MALT lymphoma, which could benefit from an upfront treatment with doxycycline. Surgery, radiotherapy, Rituximab alone or in combination with chemotherapy and "chemo-free" approaches, including lenalidomide, have shown efficacy in the treatment of non-gastric MALT lymphomas.

Whole body magnetic resonance in indolent lymphomas under watchful waiting: The time is now

ᅟ: The indolent non-Hodgkin lymphomas (i-NHLs) are characterised by 'indolent' clinical behaviour with slow growth and prolonged natural history. The watchful waiting (WW) strategy is a frequently employed treatment option in these patients. This implies a strict monitoring by imaging examinations, including 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) and CT. A major concern is radiation exposure due to regularly monitoring by conventional imaging procedures. Several studies have demonstrated the reliability of whole-body magnetic resonance imaging (WB-MRI) for lymphoma staging. WB-MRI could be useful for active surveillance in i-NHLs providing the suspect of disease progression that can be then confirmed by additional diagnostic procedures, including 18F-FDG-PET/CT. The directive 2013/59 by the European Union claims that if a radiation-free imaging technique allows obtaining the same diagnostic results, it should be invariably used. In this setting, WB-MRI may be considered a reasonable option in i-NHLs under WW, replacing imaging modalities that cause exposure to ionising radiations. This will help to reduce the cancer risk in i-NHL patients for whom chemo-/radiotherapy remain the usual treatment options following the usually long WW phase. The scientific community should raise the awareness of the risk of ionising radiations in i-NHLs and the emphasise the need for establishing the proper place of WB-MRI in lymphoma imaging.

KEY POINTS

• Watchful waiting is a reasonable option in patients with indolent non-Hodgkin lymphomas. • Imaging is crucial to monitor patients with indolent non-Hodgkin lymphomas. • CT and ¹⁸ F-FDG-PET/CT are commonly used, implying a substantial radiation exposure. • WB-MRI is highly reliable in lymphoma staging. • WB-MRI may be considered to monitor indolent non-Hodgkin lymphomas under watchful waiting.

The role of stem-cell transplantation in the treatment of marginal zone lymphoma

High-dose chemotherapy and autologous stem-cell transplantation (ASCT) is standard therapy in relapsed/refractory aggressive lymphoma. The optimal therapy of relapsed/refractory disseminated marginal-zone lymphoma (MZL) has not been defined. Limited data on ASCT in this setting suggests outcomes are similar to what is expected in follicular lymphoma. International guidelines suggest that ASCT should be considered in follicular lymphoma in second or subsequent remission, in particular in high-risk disease, or following disease transformation. These guidelines can be extrapolated to MZL. ASCT is not considered curative but a subset of patients achieve very long remissions. The major concern is the occurrence of secondary malignancies possibly related to total-body irradiation. Allogeneic SCT is usually considered after failure of ASCT, but can also be considered upfront in younger patients seeking curative approach. The introduction of novel/targeted therapies may change the role and timing SCT may have in the treatment algorithm of indolent lymphomas.

Splenic marginal zone lymphoma: a literature review of diagnostic and therapeutic challenges

Splenic marginal zone lymphoma (SMZL) is a low-grade B-cell non-Hodgkin's lymphoma characterized by massive splenomegaly, moderate lymphocytosis with or without villous lymphocytes, rare involvement of peripheral lymph nodes and indolent clinical course. As a rare disease, with no randomized prospective trials, there is no standard of care for SMZL so far. Splenectomy has been done for many years as an attempt to control disease, but nowadays it has not been encouraged as first line because of new advances in therapy as rituximab, that are as effective with minimal toxicity. Facing these controversies, this review highlights advances in the literature regarding diagnosis, prognostic factors, treatment indications and therapeutic options.

Interferon-free antiviral treatment in B-cell lymphoproliferative disorders associated with hepatitis C virus infection

Regression of hepatitis C virus (HCV)-associated lymphoma with interferon (IFN)-based antiviral treatment supports an etiological link between lymphoma and HCV infection. In addition, a favorable impact of antiviral treatment on overall survival of patients with HCV-related lymphoma has been reported. Data on IFN-free regimens combining direct-acting antivirals (DAAs) in HCV-associated lymphoproliferative disorders are scanty. We analyzed the virological and lymphoproliferative disease response (LDR) of 46 patients with indolent B-cell non-Hodgkin lymphomas (NHLs) or chronic lymphocytic leukemia (CLL) and chronic HCV infection treated with DAAs. The histological distribution was 37 marginal zone lymphomas (MZLs), 2 lymphoplasmacytic lymphomas, 2 follicular lymphomas, 4 CLL/small lymphocytic lymphomas (CLL/SLLs), and 1 low-grade NHL not otherwise specified. Thirty-nine patients received a sofosbuvir-based regimen and 7 patients received other DAAs. The median duration of DAA therapy was 12 weeks (range, 6-24 weeks). A sustained virological response at week 12 after finishing DAAs was obtained in 45 patients (98%); the overall LDR rate was 67%, including 12 patients (26%) who achieved a complete response. The LDR rate was 73% among patients with MZL, whereas no response was observed in CLL/SLL patients. Seven patients cleared cryoglobulins out of 15 who were initially positive. After a median follow-up of 8 months, 1-year progression-free and overall survival rates were 75% (95% confidence interval [CI], 51-88] and 98% [95% CI, 86-100], respectively. DAA therapy induces a high LDR rate in HCV-associated indolent lymphomas. These data provide a strong rationale for prospective trials with DAAs in this setting.

Clinicopathologic features and outcomes of lymphoplasmacytic lymphoma patients with monoclonal IgG or IgA paraprotein expression

Lymphoplasmacytic lymphoma secreting IgG or IgA (non-IgM LPL) is rarely seen. Systematic studies of the clinical features and treatment outcomes are lacking in these patients. This study evaluated 17 patients with non-IgM LPL. The paraprotein secreted by these tumors was IgA (n=8; 47%) and IgG (n=9; 53%). The median serum level of paraprotein was 2,475 mg/dl (range=747-5260) for IgA and 2580 mg/dl (range=1900-7100) for IgG. The IgA-LPL group was more likely to present with B symptoms, a high beta2-microglobulin level and extramedullary involvement. Compared with patients with Waldenström macroglobulinemia (WM), patients with non-IgM LPL showed similar clinical and pathologic features, but a higher mortality within the first year after diagnosis (p<0.001) and worse overall survival (p=0.024), with no difference in progression-free survival and disease-specific survival. Rituximab alone or rituximab-based therapy was used frequently and was effective as either first-line or salvage therapy.

Splenic marginal zone lymphoma: from genetics to management

Splenic marginal zone lymphoma (SMZL) is a rare B-cell malignancy involving the spleen, bone marrow, and frequently the blood. SMZL lymphomagenesis involves antigen and/or superantigen stimulation and molecular deregulation of genes (NOTCH2 and KLF2) involved in the physiological differentiation of spleen marginal zone B cells. Diagnosis requires either spleen histology or, alternatively, the documentation of a typical cell morphology and immunophenotype on blood cells coupled with the detection of intrasinusoidal infiltration by CD20+ cells in the bone marrow. Among B-cell tumors, deletion of 7q and NOTCH2 mutations are almost specific lesions of SMZL, thus representing promising diagnostic biomarkers of this lymphoma. Although the majority of SMZLs show an indolent course with a median survival of approximately 10 years, nearly 30% of patients experience a poor outcome. No randomized trials are reported for SMZL, and few prospective trials are available. A watch-and-wait approach is advisable for asymptomatic patients. Treatment options for symptomatic patients ranges from splenectomy to rituximab alone or combined with chemotherapy. In some geographic areas, a subset of patients with SMZL associates with hepatitis C virus infection, prompting virus eradication as an effective lymphoma treatment. It would be worthwhile to explore deregulated cellular programs of SMZL as therapeutic targets in the future; improved clinical and biological prognostication will be essential for identifying patients who may benefit from novel approaches.

Optimizing therapy for nodal marginal zone lymphoma

Nodal marginal zone lymphoma (NMZL) is a rare form of indolent small B-cell lymphoma which has only been clearly identified in the last 2 decades and which to date remains incurable. Progress in therapeutic management has been slow, largely due to the very small number of patients treated and the heterogeneity of treatments administered; thus, standard-of-care treatment is currently nonspecific for this lymphoma entity. In this review, treatments routinely used to manage adult NMZL patients are presented, principally based on immunochemotherapy (when treatment is needed). Biological research behind the key axes of agents currently under development is described; development of novel agents is heavily based on data from gene profiling and genome-wide sequencing research, uncovering a number of critical deregulated pathways specific to NMZL tumors. These include B-cell receptor, JAK/STAT, NF-κB, NOTCH, and Toll-like receptor signaling pathways, as well as intracellular processes such as the cell cycle, chromatin remodeling, and transcriptional regulation in terms of epigenetic modifiers, histones, or transcriptional co-repressors, along with immune escape via T-cell-mediated tumor surveillance. These pathways are examined in detail and a projection of how the field may evolve in the near future for an efficient personalized treatment approach for NMZL patients is presented.

Rituximab for indolent lymphomas before and after allogeneic hematopoietic stem cell transplantation

PURPOSE OF REVIEW

The most substantial advancement in the treatment of indolent B-cell non-Hodgkin lymphoma (NHL), since the advent of combination chemotherapy, has been the introduction of the monoclonal anti-CD20 antibody rituximab. However, the optimal schedule, timing, and duration of rituximab therapy remain controversial.

RECENT FINDINGS

Since its initially reported single-agent activity in 1997, the role of rituximab has greatly expanded and it is now ubiquitously integrated in all treatment phases of indolent NHL. Yet, several questions remain to be addressed: should asymptomatic patients be treated at diagnosis with single-agent rituximab or still kept in watchful waiting, what are the optimal first-line treatments to combine with rituximab, what is the role of maintenance therapy, and is there a benefit in incorporating rituximab in autologous and allogeneic stem cell transplantation schemes for these diseases? Recent and ongoing clinical trials tackling these relevant issues will be presented and critically discussed in this article.

SUMMARY

Excellent outcomes are reported with rituximab therapy in indolent NHL, both early and late in the disease course. Continued study of this most valuable therapeutic agent is warranted to set the optimal treatment approach leading to cure the majority of patients.