Phase 1b study of lenalidomide in combination with rituximab-CHOP (R2-CHOP) in patients with B-cell lymphoma

Subcutaneous Rituximab-MiniCHOP Compared With Subcutaneous Rituximab-MiniCHOP Plus Lenalidomide in Diffuse Large B-Cell Lymphoma for Patients Age 80 Years or Older

PURPOSE

The prognosis of elderly patients with diffuse large B-cell lymphoma (DLBCL) is worse than that of young patients. An attenuated dose of chemotherapy-cyclophosphamide, doxorubicin, vincristine, and prednisone plus rituximab (R-miniCHOP)-is a good compromise between efficacy and safety in very elderly patients. In combination with R-CHOP (R2-CHOP), lenalidomide has an acceptable level of toxicity and may mitigate the negative prognosis of the non-germinal center B-cell-like phenotype. The Lymphoma Study association conducted a multicentric, phase III, open-label, randomized trial to compare R-miniCHOP and R2-miniCHOP.

PATIENTS AND METHODS

Patients of age 80 years or older with untreated DLBCL were randomly assigned into the R-miniCHOP21 group or the R2-miniCHOP21 group for six cycles and stratified according to CD10 expression and age. The first cycle of rituximab was delivered by IV on D1 after a prephase and then delivered subcutaneously on D1 of cycles 2-6. Lenalidomide was delivered at a dose of 10 mg once daily on D1-D14 of each cycle. The primary end point was overall survival (OS).

RESULTS

A total of 249 patients with new DLBCL were randomly assigned (127 R-miniCHOP and 122 R2-miniCHOP). The median age was 83 years (range, 80-96), and 55% of the patients were classified as non-GCB. The delivered dose for each R-miniCHOP compound was similar in both arms. Over a median follow-up of 25.1 months, the intention-to-treat analysis revealed that R2-miniCHOP did not improve OS (2-year OS 66% in R-miniCHOP and 65.7% in R2-miniCHOP arm, P = .98) in the overall population or in the non-GCB population. Grade 3-4 adverse events occurred in 53% of patients with R-miniCHOP and in 81% of patients with R2-miniCHOP.

CONCLUSION

The addition of lenalidomide to R-miniCHOP does not improve OS. Rituximab delivered subcutaneously was safe in this population.

IMiDs New and Old

PURPOSE OF REVIEW

IMiDs are a class of biologic agents with immunomodulatory, anti-angiogenic, and direct anti-cancer activities. This review summarizes current data on clinical development and application of IMiDs in non-Hodgkin lymphoma (NHL) subtypes, focusing primarily on lenalidomide, with additional discussion on managing common side effects.

RECENT FINDINGS

Improved upon the prototype thalidomide, the second-generation compound lenalidomide has enhanced immunological and anti-cancer properties with fewer side effects, while next-generation small molecule cereblon/E3 ubiquitin ligase modulator CC-122 is in early clinical studies. Lenalidomide is FDA-approved for treatment of relapsed/refractory mantle cell lymphoma as a single agent, as well as in combination with rituximab for R/R follicular lymphoma and marginal zone lymphoma. In addition, numerous clinical trials of lenalidomide, as single agent, in combination with anti-CD20 antibodies, or in combination with chemoimmunotherapy regimens, have shown promise in aggressive and indolent NHL in both the upfront and relapsed/refractory setting. As clinical trials with lenalidomide continue to find success in both indolent and aggressive lymphomas, IMiDs are poised to be important building blocks for combinatorial strategies with antibodies, chemotherapy, novel target agents, and emerging immunotherapy involving immune checkpoint inhibitors and chimeric antigen receptor T cell (CAR-T) therapy. Delineation of treatment-specific and disease-specific biomarkers is an important research objective to gain insight into potential mechanisms of action, and to guide future clinical development.

Venous thromboembolism in patients with B-cell non-Hodgkin lymphoma treated with lenalidomide: a systematic review and meta-analysis

Lenalidomide is associated with increased risk of thromboembolism (VTE) in patients with multiple myeloma. This risk has not previously been defined in B-cell non-Hodgkin lymphoma (NHL), for which lenalidomide is also an active agent. We conducted a systematic literature search in Ovid MEDLINE (1946 to February 2017), Ovid EMBASE (1974 to February 2017), The Cochrane Library (Wiley), and Web of Science Core Collection for prospective studies evaluating lenalidomide-containing regimens in B-cell NHL with adequate reporting of patient characteristics, total cycles received, and safety data including VTE rates. The primary outcome was VTE events per 100 patient-cycles by meta-analysis using random-effects models. Our literature search identified 1719 citations; 28 articles were included. For all patients with B-cell NHL receiving lenalidomide, the rate of VTE per 100 patient-cycles was 0.77 (95% confidence interval [CI], 0.48-1.12; I², 67%). The rate for single-agent lenalidomide was 1.09 events per 100 patient-cycles (95% CI, 0.49-1.94; I², 76%), the rate for lenalidomide plus biologics was 0.49 (95% CI, 0.17-0.97; I², 59%), and the rate for lenalidomide plus chemotherapy was 0.89 (95% CI, 0.39-1.60; I², 57%). Rate of VTE events in B-cell NHL patients treated with lenalidomide in clinical trials is similar to the rate in multiple myeloma. The VTE rate appears to be lowest for lenalidomide combined with a biologic compared with single-agent lenalidomide or its combination with chemotherapy. This protocol was registered at www.crd.york.ac.uk/prospero/ as #CRD42017056042.

Total metabolic tumor volume, circulating tumor cells, cell-free DNA: distinct prognostic value in follicular lymphoma

Outcomes for follicular lymphoma (FL) have greatly improved, but most patients will ultimately relapse. High total metabolic tumor volume (TMTV), computed from baseline ¹⁸F-fluorodeoxyglucose-positron emission tomography (PET), is associated with shorter progression-free survival (PFS), but circulating tumor cells (CTCs) and cell-free DNA (cfDNA) may also reflect tumor burden and be of prognostic value. The aim of our study was to correlate CTCs and cfDNA with TMTV in FL at diagnosis and to determine their prognostic values. We retrospectively analyzed 133 patients (with previously untreated FL and a baseline PET) from 2 cohorts with either a baseline plasma sample (n = 61) or a bcl2-JH-informative peripheral blood (PB) sample (n = 68). Quantification of circulating bcl2-JH⁺ cells and cfDNA was performed by droplet digital polymerase chain reaction. A significant correlation was found between TMTV and both CTCs (P < .0001) and cfDNA (P < .0001). With a median 48-month follow-up, 4-year PFS was lower in patients with TMTV > 510 cm³ (P = .0004), CTCs >0.0018 PB cells (P = .03), or cfDNA >2550 equivalent-genome/mL (P = .04). In comparison with TMTV alone, no additional prognostic information was obtained by measuring CTCs. In contrast, Cox multivariate analysis, including cfDNA and TMTV, showed that both cfDNA and TMTV remained predictive of outcome. In conclusion, CTCs and cfDNA correlate with TMTV in FL, and all 3 influence patient outcome. PFS was shorter for patients with high cfDNA and TMTV, suggesting that these parameters provide relevant information for tumor-tailored therapy.

Venous thromboembolism in patients with non-Hodgkin lymphoma or chronic lymphocytic leukemia treated with lenalidomide: a systematic review

Lenalidomide has been associated with an increased risk of venous thromboembolism (VTE) in multiple myeloma. It is unclear whether patients with non-Hodgkin lymphoma (NHL) and chronic lymphocytic leukemia (CLL) are also at such risk. We conducted a systematic review of the incidence of VTE in prospective trials of lenalidomide-treated patients with NHL or CLL. Sixty-eight unique reports were assessed for inclusion. For grade ≥3 VTE, 98 events were reported in 3043 patients (60 studies) (crude incidence: 3.22% [95% confidence interval: 2.6-3.9%]). For any grade VTE, 97 events were reported in 2244 patients (46 studies) (crude incidence: 4.32% [3.5-5.2%]). Subgroup analysis showed no difference based on histological subtype or use of prophylaxis. The study is at risk of bias, largely due to insufficient data from the individual studies. Within the limitations of this systematic review, we found a low risk of VTE in patients with NHL treated with lenalidomide.

Diffuse large B-cell lymphoma: can genomics improve treatment options for a curable cancer?

Gene-expression profiling and next-generation sequencing have defined diffuse large B-cell lymphoma (DLBCL), the most common lymphoma diagnosis, as a heterogeneous group of subentities. Despite ongoing explosions of data illuminating disparate pathogenic mechanisms, however, the five-drug chemoimmunotherapy combination R-CHOP remains the frontline standard treatment. This has not changed in 15 years, since the anti-CD20 monoclonal antibody rituximab was added to the CHOP backbone, which first entered use in the 1970s. At least a third of patients are not cured by R-CHOP, and relapsed or refractory DLBCL is fatal in ∼90%. Targeted small-molecule inhibitors against distinct molecular pathways activated in different subgroups of DLBCL have so far translated poorly into the clinic, justifying the ongoing reliance on R-CHOP and other long-established chemotherapy-driven combinations. New drugs and improved identification of biomarkers in real time, however, show potential to change the situation eventually, despite some recent setbacks. Here, we review established and putative molecular drivers of DLBCL identified through large-scale genomics, highlighting among other things the care that must be taken when differentiating drivers from passengers, which is influenced by the promiscuity of activation-induced cytidine deaminase. Furthermore, we discuss why, despite having so much genomic data available, it has been difficult to move toward personalized medicine for this umbrella disorder and some steps that may be taken to hasten the process.

Diffuse Large B-cell Lymphoma in the elderly: standard treatment and new perspectives

INTRODUCTION

Diffuse large B-cell lymphoma (DLBCL) is the most common histotype in non Hodgkin lymphoma, with a peak incidence in the sixth decade. The standard treatment for elderly FIT DLBCL patients is Rituximab-CHOP; in unfit and frail patients, chemotherapy at reduced intensity should be considered. Areas covered: In this article, we will review use of standard therapies and new drugs investigated such as immonomudulating agents (IMiDs), Bruton Tyrosine Kinase (BTK), in fit, unfit, frail and very elderly DLCBL patients. Expert commentary: R-CHOP21 in fit DLBCL patients is still the standard of care, while in elderly unfit patients a reduction of doses of cytotoxic drugs or schemes that avoid antracycline should be considered. The Comprensive Geriatric Assesment based in age, comorbidities and functional abilities of daily living is an important tool in elderly, in order to discriminate between fit, unfit or frail patients. Novel drugs represent valid therapeutic options in relapsed/refractory setting so continued participation in clinical trials should be encouraged.

Follicular Lymphoma: The Role of the Tumor Microenvironment in Prognosis

The microenvironment of follicular lymphoma (FL) is composed of tumor-infiltrating CD8(+) T cells, follicular regulatory T cells, lymphoma-associated macrophages and mast cells, follicular helper T cells, follicular dendritic cells, and follicular reticular cells, all of which have been reported to have relevance in the prognosis of FL patients. In addition, some of these cells play a role in the histologic transformation of FL. Macrophages contribute to a poor prognosis in FL patients treated in the pre-rituximab era, but are associated with good prognosis in those treated in the rituximab era. T-cell immunoglobulin and mucin domain protein (TIM) 3 are markers of T-cell exhaustion, and T cells co-expressing programed death 1 (PD1) in peripheral blood and lymph nodes secrete interleukin (IL)-12 in the serum. Serum CXCL9, IL-2 receptor, and IL-1 receptor agonist are associated with shorter survival of FL patients. Agents for manipulation of the microenvironment surrounding FL cells include the immunomodulatory drug lenalidomide, immune check-point inhibitors, and cyclophosphamide prior to rituximab. To battle FL and to improve the outcomes of FL patients, understanding the relationship between neoplastic cells and the various microenvironmental cellular components is crucial for developing therapeutics against the microenvironment.

A comprehensive review of lenalidomide in B-cell non-Hodgkin lymphoma

Lenalidomide, an immunomodulatory drug that the US Food and Drug Administration (FDA) approved for the treatment of multiple myeloma, 5q- myelodysplasia and mantle-cell lymphoma (MCL), has encouraging efficacy in other B-cell malignancies. Its unique mechanism of action is in part due to altering the tumor microenvironment and potentiating the activity of T and natural-killer (NK) cells. Impressive clinical activity and excellent tolerability allows broad applicability. Lenalidomide has been used in a wide range of B-cell malignancies for years, but in 2013, the FDA marked its approval as a single agent only in relapsed/refractory mantle-cell lymphoma. Perhaps most impressive is the efficacy of lenalidomide when combined with monoclonal antibodies. Impressive efficacy and toxicity profiles with the combination of lenalidomide and rituximab in B-cell lymphomas in both the upfront and relapsed/refractory setting may allow a shift in our current treatment paradigm in both indolent and aggressive non-Hodgkin lymphoma (NHL). This review will summarize the current data in the relapsed/refractory and front-line setting of NHL with single-agent lenalidomide as well as its use in combination with other agents.

Lenalidomide for the treatment of B-cell lymphoma

INTRODUCTION

Although the combination of an anti-CD20 monoclonal antibody and chemotherapy has widely improved survival of patients with B-cell lymphoma, the disease still relapses. A better understanding of the biology of lymphomas has highlighted the role of the cell of origin in response to treatment and outcome. Lenalidomide represents an attractive therapeutic option due to its original mechanism of action.

AREAS COVERED

In this review, the authors describe the pharmacological properties of lenalidomide, and the rational for its use in B-cell lymphomas; focusing on diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), and mantle cell lymphoma (MCL). They discuss the mechanism of action of the drug and its current and future clinical development. They also review the current data in relapsed/refractory situations as well as in first-line treatment.

EXPERT OPINION

Lenalidomide is an oral non-chemotherapy immunomodulatory agent with an acceptable toxicity profile and manageable side-effects. Efficacy has widely been demonstrated, especially in MCL, FL and non-Germinal Center DLBCL patients. Further studies are now warranted to better define the strategy for the use of lenalidomide in B-NHL patients, and clarify which subgroup of patients will really benefit of lenalidomide as part of first-line treatment or in a relapsed/refractory setting.

Clinical experience with lenalidomide alone or in combination with rituximab in indolent B-cell and mantle cell lymphomas

Lenalidomide is an oral immunomodulatory drug with significant activity in indolent B-cell and mantle cell lymphomas. Lenalidomide has a manageable safety profile whether administered as a single agent or in combination with rituximab. The combination of lenalidomide with rituximab, known as the 'R(2)' regimen, enhances efficacy over what has been shown with monotherapy and has demonstrated activity in patients considered resistant to rituximab. Tolerability of these regimens has been consistent among studies. Asymptomatic neutropenia is the most common grade 3/4 adverse event, typically managed by dose interruption, followed by dose reduction once neutrophils have recovered. Nonhematologic toxicities (e.g. fatigue) are generally low-grade, manageable with concomitant treatment, and/or lenalidomide dose modification. More frequent with R(2), immune-related symptoms such as rash and tumor flare are important to recognize as lenalidomide-associated treatment effects in patients with lymphoma who require supportive care and potential dose modifications. Severe tumor flare reactions with painful lymphadenopathy are not typically observed outside of chronic lymphocytic leukemia/small lymphocytic lymphoma. Venous thromboembolism is uncommon in lymphomas, though prophylaxis is recommended. The general safety profile, differences between lenalidomide monotherapy and R(2) treatment, and optimal strategies for managing adverse events are discussed here.

Follicular Lymphoma: The Role of the Tumor Microenvironment in Prognosis

The microenvironment of follicular lymphoma (FL) is composed of tumor-infiltrating CD8(+) T cells, follicular regulatory T cells, lymphoma-associated macrophages and mast cells, follicular helper T cells, follicular dendritic cells, and follicular reticular cells, all of which have been reported to have relevance in the prognosis of FL patients. In addition, some of these cells play a role in the histologic transformation of FL. Macrophages contribute to a poor prognosis in FL patients treated in the pre-rituximab era, but are associated with good prognosis in those treated in the rituximab era. T-cell immunoglobulin and mucin domain protein (TIM) 3 are markers of T-cell exhaustion, and T cells co-expressing programed death 1 (PD1) in peripheral blood and lymph nodes secrete interleukin (IL)-12 in the serum. Serum CXCL9, IL-2 receptor, and IL-1 receptor agonist are associated with shorter survival of FL patients. Agents for manipulation of the microenvironment surrounding FL cells include the immunomodulatory drug lenalidomide, immune check-point inhibitors, and cyclophosphamide prior to rituximab. To battle FL and to improve the outcomes of FL patients, understanding the relationship between neoplastic cells and the various microenvironmental cellular components is crucial for developing therapeutics against the microenvironment.

Novel drug targets for personalized precision medicine in relapsed/refractory diffuse large B-cell lymphoma: a comprehensive review

Diffuse large B-cell lymphoma (DLBCL) is a clinically heterogeneous lymphoid malignancy and the most common subtype of non-Hodgkin's lymphoma in adults, with one of the highest mortality rates in most developed areas of the world. More than half of DLBLC patients can be cured with standard R-CHOP regimens, however approximately 30 to 40 % of patients will develop relapsed/refractory disease that remains a major cause of morbidity and mortality due to the limited therapeutic options.Recent advances in gene expression profiling have led to the identification of at least three distinct molecular subtypes of DLBCL: a germinal center B cell-like subtype, an activated B cell-like subtype, and a primary mediastinal B-cell lymphoma subtype. Moreover, recent findings have not only increased our understanding of the molecular basis of chemotherapy resistance but have also helped identify molecular subsets of DLBCL and rational targets for drug interventions that may allow for subtype/subset-specific molecularly targeted precision medicine and personalized combinations to both prevent and treat relapsed/refractory DLBCL. Novel agents such as lenalidomide, ibrutinib, bortezomib, CC-122, epratuzumab or pidilizumab used as single-agent or in combination with (rituximab-based) chemotherapy have already demonstrated promising activity in patients with relapsed/refractory DLBCL. Several novel potential drug targets have been recently identified such as the BET bromodomain protein (BRD)-4, phosphoribosyl-pyrophosphate synthetase (PRPS)-2, macrodomain-containing mono-ADP-ribosyltransferase (ARTD)-9 (also known as PARP9), deltex-3-like E3 ubiquitin ligase (DTX3L) (also known as BBAP), NF-kappaB inducing kinase (NIK) and transforming growth factor beta receptor (TGFβR).This review highlights the new insights into the molecular basis of relapsed/refractory DLBCL and summarizes the most promising drug targets and experimental treatments for relapsed/refractory DLBCL, including the use of novel agents such as lenalidomide, ibrutinib, bortezomib, pidilizumab, epratuzumab, brentuximab-vedotin or CAR T cells, dual inhibitors, as well as mechanism-based combinatorial experimental therapies. We also provide a comprehensive and updated list of current drugs, drug targets and preclinical and clinical experimental studies in DLBCL. A special focus is given on STAT1, ARTD9, DTX3L and ARTD8 (also known as PARP14) as novel potential drug targets in distinct molecular subsets of DLBCL.

Novelties in the management of B-cell malignancies: B-cell receptor signaling inhibitors and lenalidomide

B-cell lymphoproliferative disorders comprise 85% of Non-Hodgkin's lymphomas. Despite successful chemoimmunotherapy regimens, responses are not durable and the outcome is fatal in a considerable portion of patients. There is an inevitable need for less toxic and more potent therapeutic agents. Over the recent years, a plethora of agents including monoclonal antibodies, Bcl-2 antagonists, tyrosine kinase inhibitors, cyclin-dependent kinase inhibitors, mTOR inhibitors and immunomodulatory drugs have been developed in B-cell malignancies. The aim of this paper is to focus on B-cell receptor signaling inhibitors and lenalidomide as an immunomodulatory drug and to provide insight on how and when to incorporate these agents into the treatment algorithms.

Lymphoma: immune evasion strategies

While the cellular origin of lymphoma is often characterized by chromosomal translocations and other genetic aberrations, its growth and development into a malignant neoplasm is highly dependent upon its ability to escape natural host defenses. Neoplastic cells interact with a variety of non-malignant cells in the tumor milieu to create an immunosuppressive microenvironment. The resulting functional impairment and dysregulation of tumor-associated immune cells not only allows for passive growth of the malignancy but may even provide active growth signals upon which the tumor subsequently becomes dependent. In the past decade, the success of immune checkpoint blockade and adoptive cell transfer for relapsed or refractory lymphomas has validated immunotherapy as a possible treatment cornerstone. Here, we review the mechanisms by which lymphomas have been found to evade and even reprogram the immune system, including alterations in surface molecules, recruitment of immunosuppressive subpopulations, and secretion of anti-inflammatory factors. A fundamental understanding of the immune evasion strategies utilized by lymphomas may lead to better prognostic markers and guide the development of targeted interventions that are both safer and more effective than current standards of care.

Lenalidomide Combined With R-CHOP Overcomes Negative Prognostic Impact of Non–Germinal Center B-Cell Phenotype in Newly Diagnosed Diffuse Large B-Cell Lymphoma: A Phase II Study

Purpose

Lenalidomide has significant single-agent activity in relapsed diffuse large B-cell lymphoma (DLBCL). We demonstrated that lenalidomide can be safely combined with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone); this new combination is known as R2CHOP. The goal of this phase II study was to evaluate the efficacy of this combination in newly diagnosed DLBCL.

Patients and Methods

Eligible patients were adults with newly diagnosed untreated stages II to IV CD20+ DLBCL. Patients received lenalidomide 25 mg orally per day on days 1 through 10 with standard-dose R-CHOP every 21 days for six cycles. All patients received pegfilgrastim on day 2 of each cycle and aspirin prophylaxis throughout. DLBCL molecular subtype was determined by tumor immunohistochemistry and classified as germinal center B-cell (GCB) versus non-GCB in the R2CHOP patients and 87 control patients with DLBCL from the Lymphoma Database who were treated with conventional R-CHOP.

Results

In all, 64 patients with DLBCL were enrolled, and 60 were evaluable for response. The overall response rate was 98% (59 of 60) with 80% (48 of 60) achieving complete response. Event-free survival and overall survival (OS) rates at 24 months were 59% (95% CI, 48% to 74%) and 78% (95% CI, 68% to 90%), respectively. In R-CHOP patients, 24-month progression-free survival (PFS) and OS were 28% versus 64% (P < .001) and 46% versus 78% (P < .001) in non-GCB DLBCL versus GCB DLBCL, respectively. In contrast, there was no difference in 24-month PFS or OS for R2CHOP patients on the basis of non-GCB and GCB subtype (60% v 59% [P = .83] and 83% v 75% [P = .61] at 2 years, respectively).

Conclusion

R2CHOP shows promising efficacy in DLBCL. The addition of lenalidomide appears to mitigate a negative impact of non-GCB phenotype on patient outcome.

Novel targeted therapies in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common aggressive non-Hodgkin's lymphoma. Next-generation sequencing techniques have improved our understanding of the molecular pathways that may drive oncogenesis. Many novel classes of drugs are in development that may improve the treatment of DLBCL, either as single agents or in combination, that exploit their synergy to overcome resistance. We review the key novel targets and therapeutics in the treatment of DLBCL, including immunomodulatory agents and immunotherapy.

Indolent lymphoma: follicular lymphoma and the microenvironment-insights from gene expression profiling

As shown with gene expression profiling (GEP), the development and progression of follicular lymphoma (FL) involves complex interactions between neoplastic B cells and the surrounding microenvironment. GEP further reveals that the tumor microenvironment may predict survival in patients with FL and influence the response to therapy and the risk of transformation. Here, we briefly review GEP technology and summarize the role of the tumor microenvironment in FL diagnosis, prognosis, and transformation. Genes expressed by infiltrating T cells and macrophages appear to be the most important predictors of survival, clinical behavior, and outcome. These findings provide a basis for future studies into the pathogenesis and pathophysiology of FL and may ultimately provide guidance in the choice of therapy and the identification of potential therapeutic targets.

Therapeutic targeting of microenvironment in follicular lymphoma

Immune and nonimmune microenvironmental factors play a critical role in the progression, transformation, and resistance to therapy in follicular lymphoma (FL). A recent increase in our understanding of the role of microenvironment in FL biology has led to the development of novel therapeutic strategies targeting the nonimmune and immune microenvironment. These include immunomodulatory drugs, immune checkpoint inhibitors, immnunoconjugates, and small-molecule inhibitors with an impact on the microenvironment in addition to direct antitumor activity. These agents are now at different stages of clinical development, ranging from early clinical trials in relapsed disease to phase 3 studies in the upfront setting, including combinations with other agents such as monoclonal antibodies and chemotherapy. It is important to recognize that, although the current upfront therapy of FL is associated with favorable outcomes in the majority of patients, a significant proportion experience early disease progression and develop treatment resistance and transformation to aggressive lymphoma. Although the development of "chemo-free" combinations using drugs targeting the microenvironment offers a promising approach to minimize toxicity, the identification of patients at risk of relapse and the use of biomarkers allowing the personalization of therapy will likely play a major role in the development of maintenance strategies. Against this landscape of currently available therapy options, this chapter discusses the clinical status of therapies targeting the microenvironment in FL.

Lenalidomide in heavily pretreated refractory diffuse large B-cell lymphoma: a case report

INTRODUCTION

In diffuse large B-cell lymphoma, first-line treatment with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone; salvage with cisplatin-based regimens for relapsing patients; and autologous stem cell therapy are standards of care. Treatment approaches are less clear for patients who are refractory or who are not candidates for autologous stem cell therapy. Options may include palliative regimens or clinical trial enrollment. One therapy under investigation in diffuse large B-cell lymphoma is lenalidomide, an immunomodulatory agent with antiangiogenic activity.

CASE PRESENTATION

We present the case of a 55-year-old Caucasian male patient diagnosed with diffuse large B-cell lymphoma who had an early relapse after treatment with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone. He then had a subsequent early relapse after cisplatin-based salvage consolidated with autologous stem cell therapy. The efficacy of gemcitabine-cisplatin-rituximab was limited to five months, followed by systemic and central nervous system progression. Fourth-line treatment with lenalidomide plus rituximab and involved-field radiotherapy followed by lenalidomide monotherapy greatly improved this patient's quality of life and performance status, allowing over two years of progression-free survival to date (excluding a brief relapse due to treatment interruption).

CONCLUSION

A lenalidomide-based regimen was highly effective in this patient with diffuse large B-cell lymphoma.

The tumour microenvironment in B cell lymphomas

B cell lymphomas are cancers that arise from cells that depend on numerous highly orchestrated interactions with immune and stromal cells in the course of normal development. Despite the recent focus on dissecting the genetic aberrations within cancer cells, it has been increasingly recognized that tumour cells retain a range of dependence on interactions with the non-malignant cells and stromal elements that constitute the tumour microenvironment. A fundamental understanding of these interactions gives insight into the pathogenesis of most B cell lymphomas and, moreover, identifies novel therapeutic opportunities for targeting oncogenic pathways, both now and in the future.

Accelerated therapeutic progress in diffuse large B cell lymphoma

Diffuse large B cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma in the world. Clinically, biologically, and pathologically, DLBCL is a heterogeneous entity with a range of potential outcomes. Immunochemotherapy regimens, consisting of the chimeric monoclonal anti-CD20 antibody rituximab in combination with chemotherapy, have improved the outcomes. Relapsed DLBCL is generally treated with salvage immunochemotherapy followed by high-dose therapy and autologous stem cell transplantation; however, DLBCL is not yet curable in up to a third of patients. The real promise for cure lies in novel agents and their rational combinations. The improved understanding of DLBCL subtypes and gene expression profiling has led to the identification of targeted drugs that may allow for subtype specific therapy. We have summarized the existing data on the prognostic factors and the treatment of DLBCL, including the use of novel agents such as lenalidomide, carfilzomib, and ibrutinib. We also share our thoughts on the direction of future clinical trials.

Primary testicular lymphoma

Primary testicular lymphoma (PTL) is a rare, clinically aggressive form of extranodal lymphoma. The vast majority of cases are histologically diffuse large B-cell lymphoma, but rarer subtypes are clinically important and must be recognized. In this review, we discuss the incidence, clinical presentation, and prognostic factors of PTL and present a summary of the recent advances in our understanding of its pathophysiology, which may account for the characteristic clinical features. Although outcomes for patients with PTL have historically been poor, significant gains have been made with the successive addition of radiotherapy (RT), full-course anthracycline-based chemotherapy, rituximab and central nervous system–directed prophylaxis. We describe the larger retrospective series and prospective clinical trials and critically examine the role of RT. Although rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone given every 21 days with intrathecal methotrexate and locoregional RT is the current international standard of care, a substantial minority of patients progress, representing an unmet medical need. Finally, we discuss new treatment approaches and recent discoveries that may translate into improved outcomes for patients with PTL.

Lenalidomide plus cyclophosphamide, doxorubicin, vincristine, prednisone and rituximab is safe and effective in untreated, elderly patients with diffuse large B-cell lymphoma: a phase I study by the Fondazione Italiana Linfomi

Despite improvements in standard therapy with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone for patients with untreated, diffuse large B-cell lymphoma, up to 40% of these patients relapse. Lenalidomide alone or in combination with rituximab has been shown to be active in relapsed/refractory aggressive lymphomas. In this phase I study we determined the maximum tolerated dose of lenalidomide plus rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone in untreated, elderly (median age 68 years) patients with diffuse large B-cell lymphoma. Four lenalidomide doses (5, 10, 15, and 20 mg/day on days 1-14) allocated using the continual reassessment method were planned to be administered for 14 days in combination with each course of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone for a total of six courses. Seven cohorts of patients (n=3 in each cohort) were treated (total n=21) at 10, 20, 15, 15, 15, 10, and 10 mg of lenalidomide. Dose-limiting toxicities occurred in seven patients during the first three courses of treatment. The third dose-level of lenalidomide (15 mg/day) was selected as the maximum tolerated dose, with an estimated probability of dose-limiting toxicities of 0.345 (95% credibility interval 0.164-0.553). Grade 3-4 hematologic adverse events were: neutropenia in 28% of the courses, thrombocytopenia in 9%, and anemia in 3%. Non-hematologic toxicities were moderate: grade 4 increase of creatinine phosphokinase (n=1), grade 3 cardiac (n=2), grade 3 neurological (n=3), and grade 3 gastrointestinal (n=1). In this phase I study, the overall response rate was 90%, with 81% achieving complete remission. This combination regimen appears safe in elderly patients with diffuse large B-cell lymphoma and its efficacy will be assessed in the ongoing phase II trial. This trial was registered at www.clinicaltrials.gov as NCT00907348.

Novel CD20 monoclonal antibodies for lymphoma therapy

Rituximab (RTX), a monoclonal antibody (mAb) against CD20, has been widely used for lymphoma therapy. RTX in combination with cyclophosphamide /doxorubicin /vincristine /prednisone (R-CHOP) remains the standard frontline regimen for diffuse large B-cell lymphoma. However, suboptimal response and /or resistance to rituximab have remained a challenge in the therapy of B-cell non-Hodgkin's lymphoma (NHL). Novel agents are under active clinical trials. This review will summarize the latest development in new mAbs against CD20, which include second-generation mAbs, ofatumumab, veltuzumab (IMMU-106), ocrelizumab (PRO70769), and third-generation mAbs, AME-133v (ocaratuzumab), PRO131921 and GA101 (obinutumumab).

Rituximab and new regimens for indolent lymphoma: a brief update from 2012 ASCO Annual Meeting

Indolent lymphoma (IL), the second most common lymphoma, remains incurable with chemotherapy alone. While R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) remains the standard frontline regimen for diffuse Large B -cell lymphoma, the optimal chemotherapy regimen for frontline therapy of advanced IL remains uncertain. FCR (fludarabine, cyclophosphamide, rituximab) has been shown to be better than fludarabine alone and fludarabine plus cyclophosphamide for IL. In FOLL05 trial, R-CHOP was compared with R-CVP (cyclophosphamide, vincristine, prednisone) and R-FM (fludarabine, mitoxantrone). The study showed that R-CHOP appears to have the best risk-benefit ratio for IL. The StiL NHL1 trial showed that BR (bendamustine, rituximab) has longer progression free survival and is better tolerated than R-CHOP. Long-term complications with secondary malignancies between the two regimens appear to be comparable. In this review, new combination regimens reported at 2012 ASCO annual meeting were evaluated for frontline and salvage therapy of indolent lymphoma.