Novel Therapies for Follicular Lymphoma and Other Indolent Non-Hodgkin Lymphomas.

OPINION STATEMENT: When selecting therapy for patients with indolent non-Hodgkin lymphoma (iNHL) including follicular (FL), marginal zone (MZL), small lymphocytic (SLL), and lymphoplasmacytic lymphoma (LPL)/Waldenström macroglobulinemia (WM), there are several factors to consider. With a median age around 70 at diagnosis, many patients have accumulated comorbid conditions that may limit treatment options. Although incurable for most, iNHL is a chronic disease with a median overall survival measured in years to decades. This long natural history changes the risk-to-benefit balance with a lower acceptance of toxicity early in the treatment course compared to that of aggressive lymphomas. Despite a recent rapid increase in available therapies, overall progress in iNHL has been slow for several reasons. Initial trials grouped iNHLs together making it challenging to appreciate the differential activity among subtypes. We have not been able to develop prognostic models that maintain validity in the era of chemotherapy-free options. Predictive markers have been elusive and without identified molecular signatures, it is challenging to select and sequence therapy. With these clinical factors in mind, in addition to the heterogeneity among and within iNHLs, I do not have a standard treatment algorithm and feel each patient should have an individualized treatment approach. This review focuses on recent updates and controversies in the management of iNHL with a focus on FL and MZL.

B cell/stromal cell crosstalk in health, disease, and treatment: Follicular lymphoma as a paradigm.

Stromal cells organize specific anatomic compartments within bone marrow (BM) and secondary lymphoid organs where they finely regulate the behavior of mature normal B cells. In particular, lymphoid stromal cells (LSCs) form a phenotypically heterogeneous compartment including various cell subsets variably supporting B-cell survival, activation, proliferation, and differentiation. In turn, activated B cells trigger in-depth remodeling of LSC networks within lymph nodes (LN) and BM. Follicular lymphoma (FL) is one of the best paradigms of a B-cell neoplasia depending on a specific tumor microenvironment (TME), including cancer-associated fibroblasts (CAFs) emerging from the reprogramming of LN LSCs or poorly characterized local BM precursors. FL-CAFs support directly malignant B-cell growth and orchestrate FL permissive cell niche by contributing, through a bidirectional crosstalk, to the recruitment and polarization of immune TME subsets. Recent studies have highlighted a previously unexpected level of heterogeneity of both FL B cells and FL TME, underlined by FL-CAF plasticity. A better understanding of the signaling pathways, molecular mechanisms, and kinetic of stromal cell remodeling in FL would be useful to delineate new predictive markers and new therapeutic approaches in this still fatal malignancy.

Rare non-Hodgkin lymphoma of childhood and adolescence: A consensus diagnostic and therapeutic approach to pediatric-type follicular lymphoma, marginal zone lymphoma, and nonanaplastic peripheral T-cell lymphoma.

Pediatric-type follicular (PTFL), marginal zone (MZL), and peripheral T-cell lymphoma (PTCL) account each for <2% of childhood non-Hodgkin lymphoma. We present clinical and histopathological features of PTFL, MZL, and few subtypes of PTCL and provide treatment recommendations. For localized PTFL and MZL, watchful waiting after complete resection is the therapy of choice. For PTCL, therapy is subtype-dependent and ranges from a block-like anaplastic large cell lymphoma (ALCL)-derived and, alternatively, leukemia-derived therapy in PTCL not otherwise specified and subcutaneous panniculitis-like T-cell lymphoma to a block-like mature B-NHL-derived or, preferentially, ALCL-derived treatment followed by hematopoietic stem cell transplantation in first remission in hepatosplenic and angioimmunoblastic T-cell lymphoma.

Follicular lymphoma.

Follicular lymphoma (FL) is a systemic neoplasm of the lymphoid tissue displaying germinal centre (GC) B cell differentiation. FL represents ~5% of all haematological neoplasms and ~20-25% of all new non-Hodgkin lymphoma diagnoses in western countries. Tumorigenesis starts in precursor B cells and becomes full-blown tumour when the cells reach the GC maturation step. FL is preceded by an asymptomatic preclinical phase in which premalignant B cells carrying a t(14;18) chromosomal translocation accumulate additional genetic alterations, although not all of these cells progress to the tumour phase. FL is an indolent lymphoma with largely favourable outcomes, although a fraction of patients is at risk of disease progression and adverse outcomes. Outcomes for FL in the rituximab era are encouraging, with ~80% of patients having an overall survival of >10 years. Patients with relapsed FL have a wide range of treatment options, including several chemoimmunotherapy regimens, phosphoinositide 3-kinase inhibitors, and lenalidomide plus rituximab. Promising new treatment approaches include epigenetic therapeutics and immune approaches such as chimeric antigen receptor T cell therapy. The identification of patients at high risk who require alternative therapies to the current standard of care is a growing need that will help direct clinical trial research. This Primer discusses the epidemiology of FL, its molecular and cellular pathogenesis and its diagnosis, classification and treatment.

90 Y-ibritumomab-tiuxetan as a therapeutic alternative for follicular lymphoma (FL): A single-center experience.

BACKGROUND: Follicular lymphoma (FL) is the most frequent indolent lymphoma subtype in adults. Maintenance therapy with rituximab is frequently applied to FL patients with complete or partial response following initial chemoimmunotherapy. However, radioimmunotherapy with 90 Y-ibritumomab-tiuxetan represents a therapeutic alternative. METHODS: To compare the clinical and the prognostic impact of both therapies, a study collective of n = 56 patients diagnosed with indolent B-cell lymphoma was retrospectively investigated. The study collective was subdivided into two groups: n = 36 patients treated with rituximab maintenance therapy vs n = 20 patients treated with 90 Y-ibritumomab-tiuxetan. RESULTS: No prognostic differences for performance status, FLIPI score, gender, or B-symptoms were found for 90 Y-ibritumomab-tiuxetan or rituximab maintenance therapy. Overall survival rates and progression-free survival did not differ between both maintenance therapies. CONCLUSION: Our retrospective single-center analysis of two patient groups without major differences in prognostic parameters revealed similar outcome with two different maintenance therapies. Hence, 90 Y-ibritumomab-tiuxetan therapy might offer a valuable alternative treatment option for FL patients with partial response. However, large prospective trials are needed to confirm the reported findings.

Autologous transplantation versus allogeneic transplantation in patients with follicular lymphoma experiencing early treatment failure.

BACKGROUND: Early treatment failure (ETF) in follicular lymphoma (FL), defined as relapse or progression within 2 years of frontline chemoimmunotherapy, is a newly recognized marker of poor survival and identifies a high-risk group of patients with an expected 5-year overall survival (OS) rate of approximately 50%. Transplantation is an established option for relapsed FL, but its efficacy in this specific ETF FL population has not been previously evaluated. METHODS: This study compared autologous hematopoietic stem cell transplantation (auto-HCT) with either matched sibling donor (MSD) or matched unrelated donor (MUD) allogeneic hematopoietic cell transplantation (allo-HCT) as the first transplantation approach for patients with ETF FL (age ≥ 18 years) undergoing auto-HCT or allo-HCT between 2002 and 2014. The primary endpoint was OS. The secondary endpoints were progression-free survival, relapse, and nonrelapse mortality (NRM). RESULTS: Four hundred forty FL patients had ETF (auto-HCT, 240; MSD hematopoietic stem cell transplantation [HCT], 105; and MUD HCT, 95). With a median follow-up of 69 to 73 months, the adjusted probability of 5-year OS was significantly higher after auto-HCT (70%) or MSD HCT (73%) versus MUD HCT (49%; P = .0008). The 5-year adjusted probability of NRM was significantly lower for auto-HCT (5%) versus MSD (17%) or MUD HCT (33%; P < .0001). The 5-year adjusted probability of disease relapse was lower with MSD (31%) or MUD HCT (23%) versus auto-HCT (58%; P < .0001). CONCLUSIONS: Patients with high-risk FL, as defined by ETF, undergoing auto-HCT for FL have low NRM and a promising 5-year OS rate (70%). MSD HCT has lower relapse rates than auto-HCT but similar OS. Cancer 2018;124:2541-51. © 2018 American Cancer Society.

[Treatment of indolent cutaneous B­cell lymphoma]. / Therapie indolenter kutaner B­Zell-Lymphome.

Primary cutaneous B­cell lymphomas are rarely encountered and represent 25% of all cutaneous lymphomas. Follicular B­cell lymphoma and marginal zone lymphoma belong to indolent subtypes which as a rule have no systemic dissemination and, thus, a mostly unchanged life expectancy. Therefore, skin-directed treatment options such as excision or radiotherapy are usually sufficient to control the disease. In contrast, cutaneous diffuse large B­cell lymphoma and EBV-associated B­cell lymphomas of the skin belong to more aggressive entities which demand a systemic first-line upfront therapy with R­CHOP. Nevertheless, mortality is still high and comparable to that of systemic/nodal large B­cell lymphomas so that the identification of pathogenetic driver mutations or novel therapeutic targets may pave the way to better target-oriented therapies.

Pathways towards indolent B-cell lymphoma - Etiology and therapeutic strategies.

Although patients with indolent B-cell lymphomas have a relatively good survival rate, conventional chemotherapy is not curative. Disease courses are typically characterized by multiple relapses and progressively shorter response duration with subsequent lines of therapy. There has been an explosion of innovative targeted agents in the past years. This review discusses current knowledge on the etiology of indolent B-cell lymphomas with respect to the role of micro-organisms, auto-immune diseases, and deregulated pathways caused by mutations. In particular, knowledge on the mutational landscape of indolent B-cell lymphomas has strongly increased in recent years and harbors great promise for more accurate decision making in the current wide range of therapeutic options. Despite this promise, only in chronic lymphocytic leukemia the detection of TP53 mutations and/or del17p currently have a direct effect on treatment decisions. Nevertheless, it is expected that in the near future the role of genetic testing will increase for prediction of response to targeted treatment as well as for more accurate prediction of prognosis in indolent B-cell lymphomas.

Systemic Rituximab Immunotherapy in the Management of Primary Ocular Adnexal Lymphoma: Single Institution Experience.

PURPOSE: To evaluate the efficacy of systemic rituximab immunotherapy in the management of primary ocular adnexal lymphomas (OAL). MATERIALS AND METHODS: Clinical records of 10 consecutive patients (11 eyes) with biopsy-proven OAL managed with systemic anti-CD20 monoclonal antibody (rituximab; 375 mg/m(2) intravenously once every three weeks for 6-8 cycles) between June 2008-March 2013 were evaluated retrospectively. Orbital magnetic resonance imaging and positron emission tomography were performed to evaluate any orbital and systemic involvement, respectively. Clinical response was classified as complete or partial. RESULTS: The age of patients ranged between 27-85 (median, 55) years. Nine patients (90%) presented with unilateral and one (10%) with bilateral conjunctival involvement. Orbit was affected in 4 patients (40%), one of which had also choroidal involvement (10%). None of the patients had systemic involvement at initial presentation. All patients received an average of 7 cycles (range, 6-8) of systemic immunotherapy. After a median follow-up of 31 months (range, 10-61 months), complete response without recurrence could be achieved in 4 eyes (36%) with rituximab monotherapy. No systemic or ocular side effects were observed in any patient. Additional radiotherapy was required in 6 patients (7 eyes; 64%) with partial response or recurrence. CONCLUSIONS: Complete regression of primary OALs without recurrence was observed in about one-third of eyes after systemic rituximab monotherapy. Adjunctive radiotherapy was required in remaining two-thirds of the cases to achieve complete response. Thus, considering the balance between high rate of local control and potential ocular complications of radiotherapy, systemic rituximab can be considered as a first-line therapeutic option in the management of primary OAL.

Yttrium 90-ibritumomab tiuxetan plus rituximab maintenance as initial therapy for patients with high-tumor-burden follicular lymphoma: a Wisconsin Oncology Network study.

INTRODUCTION: Yttrium 90-ibritumomab tiuxetan (90Y-IT) radioimmunotherapy has proved to be effective in relapsed follicular lymphoma (FL). We conducted a clinical trial in which 90Y-IT followed by maintenance rituximab (MR) was evaluated as initial therapy for high-tumor-burden FL. METHODS: Eligible patients had histologically confirmed FL and met the GELF (Groupe d'Etude des Lymphomes Folliculaires) criteria for high tumor burden. All patients received a single dose of 90Y-IT. Patients with platelet counts of 150,000/mm³ or higher received 0.4 mCi/kg, and patients with platelet counts between 100,000/mm³ and 149,000/mm³ received 0.3 mCi/kg. At 6 months, patients without progressive disease (PD) received rituximab weekly for 4 weeks at a dose of 375 mg/m² (consolidation therapy), followed by MR consisting of the same dose every 3 months for a planned 5 years. RESULTS: From January 2005 through November 2007, a total of 16 patients were enrolled. The median age was 52 years (range, 37-75). The major toxicity from 90Y-IT was myelosuppression, with 88% and 31% of the patients experiencing grade 3 and grade 4 hematologic toxicity, respectively. The responses to 90Y-IT induction therapy were as follows: 7 patients with complete response/unconfirmed complete response (CR/Cru), 4 with partial response (PR), 3 with stable disease (SD), and 2 with progressive disease (PD). We identified 6 patients with early PD (range, 4-16 months) and 10 patients with prolonged remission (range, 37-101+ months). Compared with the patients who had prolonged remission, the patients who had early PD tended to have larger baseline nodal masses. The median progression-free survival (PFS) has not been reached after a median follow-up period of 48 months. The 3-year PFS and overall survival (OS) rates were 56% (95% CI, 37%-87%) and 93% (95% CI, 80%-100%), respectively. CONCLUSION: The overall response rate (ORR) to 90Y-IT was 69% in patients who had previously untreated, high-tumor-burden FL, which is lower than what is observed with contemporary rituximab/chemotherapy combinations. MR after 90Y-IT did convert all PRs to CRs. Alternative therapies should be considered for patients who have FL with large nodal masses (>9 cm), whereas very durable responses are possible in patients who have intermediate-size masses (>9 cm).

Primary cutaneous B-cell lymphomas: part II. Therapy and future directions.

The choice of therapy for primary cutaneous B-cell lymphoma (PCBCL) relies on correct histopathologic classification and the exclusion of systemic disease. In part II of this continuing medical education article, we will review the available therapies for the different types of PCBCL. Primary cutaneous follicle center lymphoma (PCFCL) and primary cutaneous marginal zone lymphoma (PCMZL) are indolent tumors with an excellent prognosis. They are managed similarly with local therapy, such as radiotherapy or surgical excision, for isolated disease and observation for asymptomatic multifocal presentations. Relapses are common in both PCFCL and PCMZL, but overall survival remains excellent. Primary cutaneous diffuse large B-cell lymphoma (both leg type and other) has a much poorer prognosis than indolent PCBCL, and it often requires an aggressive approach with radiation therapy and/or multiagent chemotherapy. Investigational approaches hold promise for the treatment of these malignancies, particularly primary cutaneous diffuse large B-cell lymphoma.

Stem cell transplantation for follicular lymphoma relapsed/refractory after prior rituximab: a comprehensive analysis from the NCCN lymphoma outcomes project.

BACKGROUND: Stem cell transplant (SCT)-related outcomes and prognostication for relapsed/refractory follicular lymphoma (FL) are not well-defined in the post-rituximab era. METHODS: Through the National Comprehensive Cancer Network (NCCN) lymphoma outcomes study, 184 patients with relapsed/refractory FL who underwent autologous SCT (autoSCT) or allogenic SCT (alloSCT) following disease relapse after prior rituximab-based therapy were examined. RESULTS: Patients who underwent autoSCT (N=136) were older compared with patients who underwent alloSCT (N=48) (54 versus 51 years, respectively, P=.01) and more frequently had grade 3 FL (35% versus 8%, respectively, P=.006). Patients who underwent alloSCT received more prior therapies (4 versus 3, respectively, P<.0001) and more often had resistant disease at SCT (19% versus 6%, respectively, P=.008). Cumulative 100-day nonrelapse mortality (NRM) for autoSCT and alloSCT were 1% and 6%, respectively (P<.0001), whereas 3-year NRM rates were 3% versus 24%, respectively (P<.0001). For autoSCT and alloSCT, cumulative rates of relapse, progression, and/or transformation were 32% versus 16%, respectively (P=.03), whereas 3-year overall survival rates were 87% versus 61% (P<.0001); there were no differences in failure-free survival. AlloSCT was associated with increased risk of death on multivariate analysis (hazard ratio=2.77, 95% confidence interval=1.46-5.26, P=.002). This finding persisted on propensity scoring/matching. Multivariate analysis for autoSCT patients identified age>60 years and>3 prior therapies as adverse factors. Furthermore, a survival model was created for the autoSCT cohort based on number of factors present (0, 1, 2); 3-year failure-free survival was 72%, 47%, and 20%, respectively (P=.0003), and 3-year overall survival was 96%, 82%, and 62%, respectively (P<.0001). CONCLUSIONS: AutoSCT remains an effective therapy for patients with FL. For alloSCT, continued strategies to reduce NRM are needed.

Patterns of use of 18-fluoro-2-deoxy-D-glucose positron emission tomography for initial staging of grade 1-2 follicular lymphoma and its impact on initial treatment strategy in the National Comprehensive Cancer Network Non-Hodgkin Lymphoma Outcomes database.

We describe the patterns of use of 18-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) for the initial staging of patients with newly diagnosed grade 1-2 follicular lymphoma (FL) and its potential impact on treatment. Data were obtained from the National Comprehensive Cancer Network Non-Hodgkin Lymphoma Outcomes database. Patients who presented between 1 January 2001 and 30 September 2009 with newly diagnosed grade 1-2 FL, with at least 6 months of follow-up, were included. We identified 953 eligible patients and 532 (56%) underwent FDG-PET as part of initial staging. Among patients who underwent FDG-PET for initial staging, 438 (82%) received early treatment compared to 259 (61.5%) of those staged without FDG-PET (p < 0.0001). Of all patients with stage I FL (n = 100), 47% were treated with radiotherapy (RT) alone, and the choice of initial treatment strategy for stage I FL did not vary significantly by use of FDG-PET (p = 0.22). The use of FDG-PET for staging of FL is widespread and is associated with a greater proportion of patients receiving early therapy. Given the widespread use and high cost of FDG-PET, its clinical utility in stage I FL should be further evaluated.

Serum selenium concentration at diagnosis and outcome in patients with haematological malignancies.

We have previously reported presentation serum selenium level to be predictive of outcome in diffuse large B-cell lymphoma. This has now been studied in a further 430 patients, 163 with acute myeloid leukaemia (AML), 156 with Hodgkin Lymphoma (HL), and 111 with Follicular Lymphoma (FL). Serum selenium was below the UK normal reference range in 45% of patients, and correlated with serum albumin (r=0·24-0·46, P<0·001-0·003) in all tumour types. Independent predictors of presentation selenium were; French-American-British subtype and albumin (P<0·001 for both) in AML, haemoglobin (P=0·002) and B-symptoms (P=0·01) in HL, and albumin (P<0·001) in FL. In AML and HL, response to first line therapy was lower in patients with low serum selenium, but selenium was no longer predictive of response when other variables were entered into a multivariate model. Low selenium was also associated with a worse overall survival in FL [Hazard Ratio (HR) 2·3, 95% confidence interval (CI) 1·4, 4·0] and a trend to a worse overall survival in AML (HR 1·43, 95% CI 0·96, 2·13) by univariate Cox regression analysis, but not by multivariate analysis. In conclusion, low serum selenium is associated with a worse outcome in patients with haematological malignancies, but is not independently predictive, suggesting that it reflects other factors.

Radioimmunotherapy of relapsed indolent non-Hodgkin lymphoma with 131I-rituximab in routine clinical practice: 10-year single-institution experience of 142 consecutive patients.

Radioimmunotherapy of indolent non-Hodgkin lymphoma (NHL) has achieved objective response rates in clinical trials comparable with standard rituximab with cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy, but is relatively underused in routine practice. In this article, we report our clinical experience in 142 consecutive patients who received iodine-131 rituximab radioimmunotherapy for low-grade, predominantly follicular, relapsed NHL. Objective response rates of 67%, with complete response (CR) in 50% and median overall survival of 32 months, matched the response rates in a phase 2 clinical trial of (131)I-rituximab radioimmunotherapy and compares favorably with those reported for (131)I-tositumomab or (90)Y-ibritumomab tiuxetan. Progression-free survival was 18 months overall and 32 months in CR or CR-unconfirmed patients. Our patients comprised 107 (75%) follicular lymphoma, 21 (15%) small lymphocytic lymphoma, 6 (4%) mucosa-associated lymphoid tissue/marginal zone lymphoma, and 8 (6%) mantle-cell lymphoma, with median follow-up of 32 months and 8-year overall survival of 48%. Toxicity was limited to hematologic grade 4 neutropenia, occurring in 10% and thrombocytopenia in 6%. There were no episodes of bleeding or infection requiring hospital admission. Radioimmunotherapy with (131)I-rituximab in routine clinical outpatient practice provides cost-effective, safe treatment of relapsed/refractory indolent NHL, with half of patients achieving durable, complete remission with potential for repeat radioimmunotherapy on relapse.

Primary cutaneous B-cell lymphomas - clinicopathological, prognostic and therapeutic characterisation of 54 cases according to the WHO-EORTC classification and the ISCL/EORTC TNM classification system for primary cutaneous lymphomas other than mycosis fungoides and Sezary syndrome.

Clinical, prognostic and therapeutic features of 54 primary cutaneous marginal zone B-cell lymphoma (pcMZL), follicle centre lymphoma (pcFCL) and diffuse large B-cell lymphoma, leg type (pcDLBL) were analysed applying the WHO-EORTC classification for cutaneous lymphomas and the new TNM staging scheme of the International Society of Cutaneous Lymphomas. Solitary (T1) or regionally clustered (T2) tumors were observed in pcMZL and pcFCL. Disseminated tumors (T3 stage) were found in 26% of patients with pcMZL and in one patient with pcDLBL. A complete remission was achieved in 41% of the patients. Three of 7 patients (43%) with pcDLBL died due to lymphoma. The new TNM staging system is easily applicable for disease documentation, but our relatively small number of patients in each T stage does not allow the assessment of its prognostic value. Surgical excision or radiotherapy is highly effective in pcMZL and pcFCL.