How I treat mantle cell lymphoma

Clinical Management of Mantle Cell Lymphoma With Concurrent Vascular Complications: A Case Report

This is a case of a 70-year-old patient with no past medical history but a significant family history of cancer, who was admitted with acute pulmonary embolism and left lower extremity deep vein thrombosis concerning malignancy. Further investigations revealed mantle cell lymphoma. This case highlights the complex clinical management of patients presenting with concurrent hematological malignancy and vascular complications.

Epidemiological, clinical and therapeutic profiles of mantle cell lymphoma cared for in a Moroccan center: a review of 14 cases

Mantle cell lymphoma (MCL) accounts for 3-10% of non-Hodgkin's lymphomas (NHL). We identified 14 patients with mantle cell lymphoma, with an average number of 3.5 new cases/year. A male predominance was observed with a sex ratio equal to 6. The average age of our patients was 64.4±14.1 years, with an average diagnostic delay of 6.57 months. Regarding the clinical presentation, adenopathy was the most reported physical sign (78.6%) followed by B symptoms (57.1%). Disseminated stages were the most frequent in our series: stages IV (78.5%) and III (7.1%) versus stages I (0%) and II (7.1%). The extra-ganglionic localizations observed were hepatic 5 cases (31.1%), pulmonary 04 cases (25%), medullary 4 cases (25%), pleural 2 cases (12.5%) and prostate 1 case (6.2%). All diagnosed cases are mantle cell lymphomas, of which 12 cases (85.7%) are classical and 2 cases (14.3%) indolent. The high-risk group is, according to international prognostic index (MIPI) MCL prognostic score, the most represented in our series: 0-3 = 6 cases (42.9%), 6-11 = 8 cases (57.1%). The therapeutic protocol chosen 1st line: 9 patients treated with R-DHAP, three with R-CHOP, one with DHAOX and one with R-CVP. Second line: two patients treated with R-DHAP, one after R-CHOP and the other after R-CVP. Two patients received autologous hematopoietic stem cell transplant at the end of the treatment. The evolution was marked by the death of 7 patients, 3 lost to follow-up and 4 still followed. Additionally, the study highlights characteristics and treatment patterns of mantle cell lymphoma, emphasizing its predominance in males, delayed diagnosis, frequent dissemination, and high-risk classification, with chemotherapy as the primary treatment modality and a challenging prognosis contributing to a comprehensive understanding of mantle cell lymphoma presentation and management.

Survival Outcomes of Patients with Mantle Cell Lymphoma: A Retrospective, 15-Year, Real-Life Study

Mantle cell lymphoma (MCL) prognosis has significantly improved in recent years; however, the possible survival benefit of new treatment options should be evaluated outside of clinical trials. We investigated 73 consecutive MCL patients managed from 2006 to 2020. For younger patients <65 years old, the median PFS was 72 months and we reported a 2-year, 5-year, and 10-year PFS of 73%, 62%, and 41%; median OS was not reached and we reported a 2-year, 5-year, and 10-year OS of 88%, 82%, and 66%. For patients aged 75 years or older, the median PFS was 36 months and we reported a 2-year, 5-year, and 10-year PFS of 52%, 37%, and 37%; median OS was not reached and we reported a 2-year, 5-year, and 10-year OS of 72%, 55%, and 55%. The median PFS was significantly reduced for patients treated between 2006 and 2010 compared to patients treated between 2011 and 2015 (p = 0.04). Interestingly, there was a trend towards improved OS for patients treated between 2016 and 2020 compared to between 2006 and 2010 and between 2011 and 2015 (5-year OS was 91%, 44%, and 33%). These findings could be due to the introduction of BR as a first-line regimen for elderly patients and to the introduction of ibrutinib as a second-line regimen.

Up-Front ASCT Overcomes the Survival Benefit Provided by HDAC-Based Induction Regimens in Mantle Cell Lymphoma: Data from a Real-Life and Long-Term Cohort

BACKGROUND

Mantle cell lymphoma (MCL) is a rare malignancy with heterogeneous behavior. Despite the therapeutic advances recently achieved, MCL remains incurable. Currently, the standard of care for young and fit patients involves induction immunochemotherapy followed by up-front autologous stem cell transplantation (ASCT). However, the role of more intensive induction regimens, such as those based on high doses of cytarabine (HDAC), remains controversial in the management of ASCT-eligible patients.

METHODS

This retrospective, observational, and single-center study involved 165 MCL patients treated at the largest oncology center in Latin America from 2010 to 2022. We aimed to assess outcomes, determine survival predictors, and compare responses between different primary therapeutic strategies, with a focus on assessing the impact of HDAC-based regimens on outcomes in ASCT-eligible patients.

RESULTS

The median age at diagnosis was 65 years (38-89 years), and 73.9% were male. More than 90% of the cases had a classic nodal form (cnMCL), 76.4% had BM infiltration, and 56.4% presented splenomegaly. Bulky ≥ 7 cm, B-symptoms, ECOG ≥ 2, and advanced-stage III/IV were observed in 32.7%, 64.8%, 32.1%, and 95.8%, respectively. Sixty-four percent of patients were categorized as having high-risk MIPI. With a median follow-up of 71.1 months, the estimated 2-year OS and EFS were 64.1% and 31.8%, respectively. Patients treated with (R)-HDAC-based regimens had a higher ORR (85.9% vs. 65.7%, p = 0.007) compared to those receiving (R)-CHOP, as well as lower POD-24 rates (61.9% vs. 80.4%, p = 0.043) and lower mortality (43.9% vs. 68.6%, p = 0.004). However, intensified induction regimens with (R)-HDAC were not associated with a real OS benefit in MCL patients undergoing up-front consolidation with ASCT (2-year OS: 88.7% vs. 78.8%, p = 0.289). Up-front ASCT was independently associated with increased OS (p < 0.001), EFS (p = 0.005), and lower POD-24 rates (p < 0.001) in MCL. Additionally, CNS infiltration, TLS, hypoalbuminemia, and the absence of remission after induction were predictors of poor OS.

CONCLUSIONS

In the largest Latin American cohort of MCL patients, we confirmed the OS benefit promoted by up-front consolidation with ASCT in young and fit patients, regardless of the intensity of the immunochemotherapy regimen used in the pre-ASCT induction. Although HDAC-based regimens were not associated with an unequivocal increase in OS for ASCT-eligible patients, it was associated with higher ORR and lower rates of early relapses for the whole cohort.

Evaluation of Bortezomib-BeEAM (2BeEAM) as Chemotherapy Regimen Prior to ASCT in Patients with Mantle Cell Lymphoma

(1) Background: First-line therapy in fit MCL patients may comprise high-dose chemotherapy (HDCT) with autologous transplantation to consolidate remission before maintenance treatment. However, optimization of HDCT is an unmet clinical need given the substantial relapse rate of first-line treatment, while the use of bortezomib is a promising candidate to be added to standard HDCT. (2) Methods: We analyzed 11 consecutive patients with MCL who received bortezomib added to standard BeEAM (2BeEAM) HDCT at a single academic institution. We assessed safety, feasibility, toxicities, and survival rates. (3) Results: All patients had stage III or IV disease. We found that six patients (55%) developed new or worsening of preexisting peripheral neuropathy following administration of 2BeEAM HDCT. One patient relapsed within the first six months after HDCT, whereas three patients never reached complete remission. After a median follow-up of 22 months, the PFS was 64% and the OS 64% at the last follow-up assessment. At this time, 55% of patients were in CR. (4) Conclusions: The use of bortezomib added to standard BeEAM HDCT is associated with relevant toxicities, particularly with regards to additional neuropathy. Moreover, the anti-lymphoma efficacy of 2BeEAM HDCT appears to be modest; therefore, other therapeutic options should be evaluated for consolidation in this patient group.

Unusual Presentation of Leukemic-Phase Mantle Cell Lymphoma: A Case Report

Mantle cell lymphoma (MCL) is a rare subtype of B-cell lymphoma that can present in a variety of ways, including the leukemic phase, where it can occasionally be mistaken for acute leukemia due to the unusually high or rapidly growing number of leukocytes and the presence of circulating cancer cells that are morphologically similar to leukemic blasts in myeloid or acute lymphoblastic leukemia. We present the case of an 83-year-old Yemeni woman with multiple comorbidities who presented with abdominal pain and constitutional symptoms. She was found to have diffuse lymphadenopathy on clinical and radiological assessments. Her white blood cell count at presentation was 221 × 10⁹/L with marked monocytosis (72.8%). Lymph node biopsy and bone marrow studies, including CCND1/IGH molecular studies, confirmed MCL, the pleomorphic subtype. The patient was deemed unfit for standard-of-care chemotherapy and was started on single-agent rituximab with a slow introduction to ibrutinib but succumbed to death after two weeks of ibrutinib 280 mg daily. This case serves as a reminder to keep an open mind and take into account atypical disease presentations when formulating differential diagnoses to prevent late diagnosis and any unnecessary intervention that can postpone appropriate therapy.

A FOXO1-dependent transcription network is a targetable vulnerability of mantle cell lymphomas

Targeting lineage-defined transcriptional dependencies has emerged as an effective therapeutic strategy in cancer treatment. Through screening for molecular vulnerabilities of mantle cell lymphoma (MCL), we identified a set of transcription factors (TFs) including FOXO1, EBF1, PAX5, and IRF4 that are essential for MCL propagation. Integrated chromatin immunoprecipitation and sequencing (ChIP-Seq) with transcriptional network reconstruction analysis revealed FOXO1 as a master regulator that acts upstream in the regulatory TF hierarchy. FOXO1 is both necessary and sufficient to drive MCL lineage commitment through supporting the lineage-specific transcription programs. We further show that FOXO1, but not its close paralog FOXO3, can reprogram myeloid leukemia cells and induce B-lineage gene expression. Finally, we demonstrate that cpd10, a small molecule identified from an enriched FOXO1 inhibitor library, induces a robust cytotoxic response in MCL cells in vitro and suppresses MCL progression in vivo. Our findings establish FOXO1 inhibition as a therapeutic strategy targeting lineage-driven transcriptional addiction in MCL.

The Serum- and Glucocorticoid-Inducible Kinase 1 (SGK1) as a Novel Therapeutic Target in Mantle Cell Lymphoma

INTRODUCTION

Mantle cell lymphoma (MCL) is an aggressive and incurable B-cell-derived malignant disease. MCL is treated using general chemotherapy; however, disease progression and relapse are common; thus, the development of novel therapeutic targets for treatment of MCL is urgently required. Serum- and glucocorticoid-inducible kinase 1 (SGK1) is involved in various cellular activities, and its dysregulation contributes to the pathogenesis of multiple types of cancer. However, little is known regarding its functional roles and associated molecular mechanisms in MCL.

METHODS

SGK1 inhibition mediated by either shRNA or treatment with SGK1 inhibitor (GSK650394) was conducted in MCL cell lines. Western blotting analysis was performed to figure out the expression of related proteins. MCL-cell-derived xenograft models were constructed to evaluate the anti-tumor effects of SGK1 inhibition or/and Bruton's tyrosine kinase (BTK) inhibition in vivo.

RESULTS

In this study, it was shown that inhibition of SGK1 significantly reduced cell proliferation, invasion and migration, increased apoptosis and blocked cell cycle progression in MCL cells. Furthermore, SGK1 inhibition significantly reduced the activation of ERK, AKT/mTOR, JAK2/STAT3 and the NF-κB signaling pathways. Using MCL-cell-derived xenograft mice models, SGK1 inhibition decreased tumor cell proliferation and tumor growth. Importantly, SGK1 overexpression significantly promoted xenograft tumor growth. Moreover, simultaneous inhibition of SGK1 and Bruton tyrosine kinase (BTK) resulted in synergistic anti-tumor effects on MCL both in vitro and in vivo.

CONCLUSION

SGK1 may be a novel candidate therapeutic target and simultaneous inhibition of SGK1 and BTK may be a promising therapeutic strategy for MCL patients. Further pre-clinical and even clinical studies of SGK1 inhibitor or combination with BTK inhibitor are essential.

Whole Transcriptome Sequencing Reveals Cancer-Related, Prognostically Significant Transcripts and Tumor-Infiltrating Immunocytes in Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is an aggressive B-cell non-Hodgkin lymphoma (NHL) subtype characterized by overexpression of CCND1 and SOX11 genes. It is generally associated with clinically poor outcomes despite recent improvements in therapeutic approaches. The genes associated with the development and prognosis of MCL are still largely unknown. Through whole transcriptome sequencing (WTS), we identified mRNAs, lncRNAs, and alternative transcripts differentially expressed in MCL cases compared with reactive tonsil B-cell subsets. CCND1, VCAM1, and VWF mRNAs, as well as MIR100HG and ROR1-AS1 lncRNAs, were among the top 10 most significantly overexpressed, oncogenesis-related transcripts. Survival analyses with each of the top upregulated transcripts showed that MCL cases with high expression of VWF mRNA and low expression of FTX lncRNA were associated with poor overall survival. Similarly, high expression of MSTRG.153013.3, an overexpressed alternative transcript, was associated with shortened MCL survival. Known tumor suppressor candidates (e.g., PI3KIP1, UBXN) were significantly downregulated in MCL cases. Top differentially expressed protein-coding genes were enriched in signaling pathways related to invasion and metastasis. Survival analyses based on the abundance of tumor-infiltrating immunocytes estimated with CIBERSORTx showed that high ratios of CD8⁺ T-cells or resting NK cells and low ratios of eosinophils are associated with poor overall survival in diagnostic MCL cases. Integrative analysis of tumor-infiltrating CD8⁺ T-cell abundance and overexpressed oncogene candidates showed that MCL cases with high ratio CD8⁺ T-cells and low expression of FTX or PCA3 can potentially predict high-risk MCL patients. WTS results were cross-validated with qRT-PCR of selected transcripts as well as linear correlation analyses. In conclusion, expression levels of oncogenesis-associated transcripts and/or the ratios of microenvironmental immunocytes in MCL tumors may be used to improve prognostication, thereby leading to better patient management and outcomes.

Clinicopathologic Features and Treatment of CD10-Positive Mantle Cell Lymphoma: A Case Report and Review of Literature

Mantle cell lymphoma (MCL) is a rare and aggressive non-Hodgkin’s B cell lymphoma characterized by the translocation t(11;14) (q13;32) and overexpression of CCND1. MCL is immunophenotypically identified as CD20⁺, CD5⁺, CyclinD1+, CD43⁺, CD10⁻, BCL6⁻, and CD23⁻. It is often distinguished from B cell lymphomas of germinal center cell origin by the absence of CD10 expression. Here we report the unique clinicopathologic features of a patient with CD10⁺ MCL with gastrointestinal involvement and review current literature identifying this unique immunophenotype.

Combined epigenetic and immunotherapy for blastic and classical mantle cell lymphoma

Classical MCL (cMCL) constitutes 6-8% of all B cell NHL. Despite recent advances, MCL is incurable except with allogeneic stem cell transplant. Blastic mantle cell lymphoma (bMCL) is a rarer subtype of cMCL associated with an aggressive clinical course and poor treatment response, frequent relapse and poor outcomes. We treated 13 bMCL patients with combined epigenetic and immunotherapy treatment consisting of vorinostat, cladribine and rituximab (SCR). We report an increased OS greater than 40 months with several patients maintaining durable remissions without relapse for longer than 5 years. This is remarkably better then current treatment regimens which in bMCL range from 14.5-24 months with conventional chemotherapy regimens. We demonstrate that the G/A870 CCND1 polymorphism is predictive of blastic disease, nuclear localization of cyclinD1 and response to SCR therapy. The major resistance mechanisms to SCR therapy are loss of CD20 expression and evasion of treatment by sanctuary in the CNS. These data indicate that administration of epigenetic agents improves efficacy of anti-CD20 immunotherapies. This approach is promising in the treatment of MCL and potentially other previously treatment refractory cancers.

Mantle cell lymphoma negative for t(11,14) involving the kidneys: a case report

Background

Mantle cell lymphoma is the rarest subtype of non-Hodgkin’s lymphoma. It can exhibit diverse extranodal manifestations. However, renal involvement is uncommon, and if it occurs, it usually only gets detected postmortem. There are several mechanisms by which mantle cell lymphoma can damage the kidneys. Renal failure is a potential complication, and prompt evaluation and diagnosis are critical steps to prevent long-term complications.

Case presentation

We present the case of a 75-year-old non-Hispanic White male with past medical history significant for hypertension and dyslipidemia, presenting with fever, weight loss, and night sweats. Work-up showed markedly elevated white blood cells, multiple enlarged lymph nodes, and a kidney mass. The patient was diagnosed with mantle cell lymphoma with kidney involvement confirmed with a kidney biopsy. His disease was positive for cyclin D1 overexpression despite t(11; 14) absence. The patient received six cycles of alternating vincristine, rituximab, cyclophosphamide, doxorubicin, and prednisone then dexamethasone, high-dose cytarabine, and oxaliplatin, after which he was maintained on ibrutinib and rituximab, with resolution of symptoms and disease regression.

Conclusion

We present a case of a rare presentation of Mantle cell lymphoma while describing the clinical presentation and diagnostic and treatment approaches. This case report can assist physicians in the clinical work-up and treatment of patients with similar diagnosis or presentation.

Mantle cell lymphoma with endobronchial involvement: A case report

BACKGROUND

Mantle cell lymphoma (MCL) is a subtype of Non-Hodgkin's lymphoma (NHL). MCL frequently affects extranodal sites while endobronchial involvement is uncommon. Only 5 cases of MCL with endobronchial involvement have been previously reported.

CASE SUMMARY

A 56-year-old male patient arrived at the hospital complaining of a dry cough. A mass in the right upper lobe of the lung was revealed in Chest computed tomography (CT). Right lung hilar and mediastinal lymphadenopathies were also found by CT scan. The patient was diagnosed with central-type lung cancer with multiple lymph node metastases after positron emission tomography (PET) CT scan examination. The fiber optic bronchoscope examination revealed diffuse neoplasm infiltration in the inlet of the right up lobar bronchus. The patient was finally diagnosed with MCL based on the bronchoscopy and mediastinoscopy biopsy results.

CONCLUSION

MCL could masquerade as central type lung cancer. An endobronchial biopsy examination is necessary for the early diagnosis of MCL.

P300/CBP inhibition sensitizes mantle cell lymphoma to PI3Kδ inhibitor idelalisib

Mantle cell lymphoma (MCL) is a lymphoproliferative disorder lacking reliable therapies. PI3K pathway contributes to the pathogenesis of MCL, serving as a potential target. However, idelalisib, an FDA-approved drug targeting PI3Kδ, has shown intrinsic resistance in MCL treatment. Here we report that a p300/CBP inhibitor, A-485, could overcome resistance to idelalisib in MCL cells in vitro and in vivo. A-485 was discovered in a combinational drug screening from an epigenetic compound library containing 45 small molecule modulators. We found that A-485, the highly selective catalytic inhibitor of p300 and CBP, was the most potent compound that enhanced the sensitivity of MCL cell line Z-138 to idelalisib. Combination of A-485 and idelalisib remarkably decreased the viability of three MCL cell lines tested. Co-treatment with A-485 and idelalisib in Maver-1 and Z-138 MCL cell xenograft mice for 3 weeks dramatically suppressed the tumor growth by reversing the unsustained inhibition in PI3K downstream signaling. We further demonstrated that p300/CBP inhibition decreased histone acetylation at RTKs gene promoters and reduced transcriptional upregulation of RTKs, thereby inhibiting the downstream persistent activation of MAPK/ERK signaling, which also contributed to the pathogenesis of MCL. Therefore, additional inhibition of p300/CBP blocked MAPK/ERK signaling, which rendered maintaining activation to PI3K-mTOR downstream signals p-S6 and p-4E-BP1, thus leading to suppression of cell growth and tumor progression and eliminating the intrinsic resistance to idelalisib ultimately. Our results provide a promising combination therapy for MCL and highlight the potential use of epigenetic inhibitors targeting p300/CBP to reverse drug resistance in tumor.

Longitudinal CT Imaging to Explore the Predictive Power of 3D Radiomic Tumour Heterogeneity in Precise Imaging of Mantle Cell Lymphoma (MCL)

The study's primary aim is to evaluate the predictive performance of CT-derived 3D radiomics for MCL risk stratification. The secondary objective is to search for radiomic features associated with sustained remission. Included were 70 patients: 31 MCL patients and 39 control subjects with normal axillary lymph nodes followed over five years. Radiomic analysis of all targets (n = 745) was performed and features selected using the Mann Whitney U test; the discriminative power of identifying "high-risk MCL" was evaluated by receiver operating characteristics (ROC). The four radiomic features, "Uniformity", "Entropy", "Skewness" and "Difference Entropy" showed predictive significance for relapse (p < 0.05)-in contrast to the routine size measurements, which showed no relevant difference. The best prognostication for relapse achieved the feature "Uniformity" (AUC-ROC-curve 0.87; optimal cut-off ≤0.0159 to predict relapse with 87% sensitivity, 65% specificity, 69% accuracy). Several radiomic features, including the parameter "Short Axis," were associated with sustained remission. CT-derived 3D radiomics improves the predictive estimation of MCL patients; in combination with the ability to identify potential radiomic features that are characteristic for sustained remission, it may assist physicians in the clinical management of MCL.

Targeting Wee1 kinase as a therapeutic approach in Hematological Malignancies

Hematologic malignancies include various diseases that develop from hematopoietic stem cells of bone marrow or lymphatic organs. Currently, conventional DNA-damage-based chemotherapy drugs are approved as standard therapeutic regimens for these malignancies. Although many improvements have been made, patients with relapsed or refractory hematological malignancies have a poor prognosis. Therefore, novel and practical therapeutic approaches are required for the treatment of these diseases. Interestingly several studies have shown that targeting Wee1 kinase in the Hematological malignancies, including AML, ALL, CML, CLL, DLBCL, BL, MCL, etc., can be an effective therapeutic strategy. It plays an essential role in regulating the cell cycle process by abrogating the G2-M cell-cycle checkpoint, which provides time for DNA damage repair before mitotic entry. Consistently, Wee1 overexpression is observed in various Hematological malignancies. Also, in healthy normal cells, repairing DNA damages occurs due to G1-S checkpoint function; however, in the cancer cells, which have an impaired G1-S checkpoint, the damaged DNA repair process depends on the G2-M checkpoint function. Thus, Wee1 inhibition could be a promising target in the presence of DNA damage in order to potentiate multiple therapeutic drugs. This review summarized the potentials and challenges of Wee1 inhibition combined with other therapies as a novel effective therapeutic strategy in Hematological malignancies.

Relapsed/Refractory Non-Hodgkin Lymphoma: Engineering T-Cells to Express Chimeric Antigen Receptors (CARs), a Salvage?

For years, patients with B-cell non-Hodgkin lymphoma (NHL) have been treated with traditional first-line therapies with a fairly acceptable outcome. However, some individuals with relapsed or resistant lymphoma do not respond to those treatments, including chemotherapy, immunotherapy, radiotherapy, and (or) autologous stem cell transplantation. Based on the acquired immunotherapy knowledge, T-cells genetically engineered with chimeric antigen receptors (CARs) seem to offer complete, enduring clinical responses to patients with refractory or relapsed lymphomas. Currently, four autologous CD19-directed CAR T-cell therapies have gained approval by the U.S. Food and Drug Administration (FDA) for the treatment of relapsed or refractory diffuse large B-cell lymphoma (DLBCL), primary mediastinal B-cell lymphoma, high-grade B-cell lymphoma, and transformed follicular lymphoma, while further CAR T-cell immunotherapies have entered the clinical trials pipeline. This review aims to summarize the efficacy and safety of the FDA-approved CAR T-cell treatments for the relapsed or refractory lymphomas.

Migration and Adhesion of B-Lymphocytes to Specific Microenvironments in Mantle Cell Lymphoma: Interplay between Signaling Pathways and the Epigenetic Landscape

Lymphocyte migration to and sequestration in specific microenvironments plays a crucial role in their differentiation and survival. Lymphocyte trafficking and homing are tightly regulated by signaling pathways and is mediated by cytokines, chemokines, cytokine/chemokine receptors and adhesion molecules. The production of cytokines and chemokines is largely controlled by transcription factors in the context of a specific epigenetic landscape. These regulatory factors are strongly interconnected, and they influence the gene expression pattern in lymphocytes, promoting processes such as cell survival. The epigenetic status of the genome plays a key role in regulating gene expression during many key biological processes, and it is becoming more evident that dysregulation of epigenetic mechanisms contributes to cancer initiation, progression and drug resistance. Here, we review the signaling pathways that regulate lymphoma cell migration and adhesion with a focus on Mantle cell lymphoma and highlight the fundamental role of epigenetic mechanisms in integrating signals at the level of gene expression throughout the genome.

Is Limited-Stage Mantle Cell Lymphoma Curable and How Is It Best Managed?

Limited-stage (stage I-II) mantle cell lymphoma (MCL) is rarely encountered. There is no standard approach to treatment and available data to guide management decisions mainly are retrospective studies. A thorough staging evaluation, including positron emission tomography/computed tomography, bone marrow biopsy, and gastrointestinal evaluation, should be completed because disseminated disease is common. Radiation therapy is effective for local control, and, although prolonged remission can be achieved, distant relapses are common and there are insufficient data to say that patients can be cured using this treatment. This article reviews literature pertaining to management of patients with limited-stage MCL and discusses approach to treatment.

Exosome complex genes mediate RNA degradation and predict survival in mantle cell lymphoma

Exosome complex (EXOSC) genes, which encode a multi-protein intracellular complex, mediate the degradation of various types of RNA molecules. EXOSCs, also known as polymyositis/scleroderma complexes, exist in eukaryotic cells and archaea, and primarily mediate 3′ to 5′mRNA degradation. However, how EXOSC genes are implicated in processes of B-cell immune-associated pathways and B-cell tumorigenesis remains unclear. The present bioinformatics study indicated that 6 of 10 EXOSC genes, particularly the EXO.index, were able to predict the survival of patients with mantle cell lymphoma (MCL), by analyzing gene expression profiles of 123 patients with MCL from the Gene Expression Omnibus database. The results suggested that EXOSC gene expression may be a molecular marker for MCL. Compared with the whole transcript profile, patients with MCL with a high EXO.index exhibited poorer survival and decreased RNA levels, which was also verified in a second dataset. The EXOSC genes may be associated with DNA repair and B-cell activation pathways, which may be the cause of poorer survival of patients with MCL.

Venetoclax: evidence to date and clinical potential

The emergence of targeted therapy for patients with hematological diseases has permanently altered the therapeutic landscape. Immunochemotherapy regimes are now more and more being replaced by targeted therapies due to superior efficacy and better safety profiles. However, evolution and selection of subclones with continuous treatment leads to disease relapse and resistance toward these novel drugs. Venetoclax, the highly selective BCL-2 inhibitor (ABT-199), has an acceptable safety profile. To date, it has been approved for the treatment of first-line and relapsed/refractory chronic lymphocytic leukemia (CLL) and acute myeloid leukemia (AML). However, extension of indications can be expected in monotherapy and in combination regimens with promising outcomes in other hematological diseases. In this article, we describe the mechanism of action that stands behind the efficacy of venetoclax and provide a summary of available results from clinical trials.

A Rare Manifestation of a Rare Disease: Mantle Cell Lymphoma Presenting With Aseptic Meningitis

Mantle cell lymphoma (MCL) is a rare form of non-Hodgkin lymphoma characterized by clonal proliferation of follicular mantle zone B lymphocytes. It is caused by abnormal chromosomal translocation t(11;14) resulting in aberrant expression of cyclin D1. This leads to activation of anti-apoptotic pathways and abnormal proliferation of MCL cells. Patients can present with an indolent course or a fulminant disease with short overall survival. The disease frequently involves extranodal organs, but rarely manifests with neurological symptoms. We report a rare case of aberrant CD5-negative MCL presenting with aseptic meningitis.

Gastrointestinal Perforation after Rituximab Therapy in Mantle Cell Lymphoma: A Case Report

Mantle cell lymphoma (MCL) is a rare form of non-Hodgkin lymphoma (NHL), responsible for 2.8% of all NHL cases within the United States. The majority of patients with MCL present with advanced disease, 10–20% of which have extra-nodal involvement at diagnosis. The gastrointestinal presence of lymphoma can lead to gastrointestinal perforation, resulting in significant morbidity from peritonitis and sepsis while prolonging hospitalizations and delaying treatment. In this case we discuss a 55-year-old male with newly diagnosed MCL who developed peritonitis 9 days after initiation of dose reduced rituximab due to gastrointestinal perforation. Although prognostication factors for MCL such as the mantle cell lymphoma international prognostic index (MIPI) score exist, further research is needed to stratify risk factors for morbid treatment complications such as gastrointestinal perforation.

Frontline Treatment for Older Patients with Mantle Cell Lymphoma

The natural history of mantle cell lymphoma (MCL) undergoing chemotherapy is a cyclical pattern of remission followed by recurrence of disease due to acquired chemotherapy resistance. The median age of the occurrence of MCL is 65 years, so half of the newly diagnosed MCL patients are considered "elderly." The tolerance to long-term chemotherapy in elderly patients is decreased; hence, the response to frontline therapy used is of paramount importance. We hope that our review may guide clinicians in treating such populations in a more personalized and evidence-based manner.In the older patients with risk variables, frontline treatment is determined according to different body status of fit, unfit or compromised, and frail. In the fit patients, the pursuit of remission and prolongation of survival might currently justify the use of more intense and toxic therapies. For unfit or compromised older patients, disease control needs to be prioritized, maintaining a balance between the benefits and toxicities of the treatment. For frail patients, tolerance of treatment and minimizing myelotoxicity should be the primary focus. "Chemotherapy-free" regimens are likely to be considered as the first-line strategy for this population. On the other hand, in the older MCL population without risk variables, observation or "watch and wait" can prevent overtreatment. Furthermore, more clinical trials and research studies on novel agents and targeted therapies need to be translated into the general population to provide optimal treatment and to guide personalized treatment. IMPLICATIONS FOR PRACTICE: This review emphasizes the importance of frontline therapies for older MCL patients. MCL patients commonly experience a cyclical pattern of remission followed by recurrence of disease due to acquired chemotherapy resistance. As a special population, elderly patients have various comorbidities and decreased organ function, which may reduce the chances of undergoing treatment for recurrent disease. Thus, this older population of patients with MCL should be treated separately and exceptionally. So far, systematic reviews with regard to frontline treatment for older patients with MCL have not been encountered, but the hope is that this review may guide clinicians in treating such populations in a more personalized and evidence-based manner.

Toward a Risk-Tailored Therapeutic Policy in Mantle Cell Lymphoma

PURPOSE OF REVIEW

Mantle cell lymphoma (MCL) prognosis is strictly related to the characteristics of the disease, which can range from very indolent cases to highly aggressive and refractory ones. Here we will review the current knowledge on MCL biomarkers.

RECENT FINDINGS

Biomarker-informed diagnosis is essential for differentiating MCL from other mature B cell tumors. Diagnosis of MCL relies on the identification of the t(11;14) translocation by FISH or the consequently aberrant expression of cyclin D1 by immunohistochemistry. For the few cases staining negative for cyclin D1, SOX11 may help to define the diagnosis. Prognostic biomarkers have been proposed to stratify MCL patients, including baseline clinical aspects (leukemic non-nodal presentation, in situ presentation, Mantle cell International Prognostic Index-MIPI), pathological aspects (blastoid morphology, Ki-67 proliferation index, SOX11 expression), genetic aspects (immunoglobulin gene mutation status, TP53 deletion or mutation, CDKN2A deletion), and depth of response after treatment (PET imaging, molecular minimal residual disease). Such tools are increasingly used as a guide for therapeutic decisions. Watchful waiting approach is recommended for patients harboring favorable clinico-biological features, such as leukemic non-nodal presentation, low MIPI score, non-blastoid disease, low Ki-67 proliferation rate, mutated immunoglobulin genes, and the lack of SOX11 expression. For patients in need of frontline therapy, the decision of whether to undertake intensive regimens is based upon patient's age and comorbidities. Central nervous system prophylaxis is recommended for cases showing blastoid morphology. The duration of remission is tightly correlated to the depth of response. With the aim of achieving a longer duration of remission and survival, younger patients may pursue more intensive regimens incorporating high-dose cytarabine, followed by myeloablative consolidation chemotherapy, autologous stem cell transplantation, and rituximab maintenance. Older patients could, on the other hand, benefit from lower intensity immunochemotherapy followed or not by a maintenance therapy depending on which frontline regimen is used. Despite the identification of several potential useful biomarkers that may inform the treatment decisions and the design of clinical trials, the treatment choice remains nowadays determined by the patient age and fitness rather than by the individual patient characteristics. Tailoring therapy toward a risk-adapted strategy to accommodate the wide spectrum of disease is an urgent challenge, and clinical trials may explore the feasibility of a biomarker-defined therapeutic policy.

Targeting the PI3K/Akt/mTOR signaling pathway by pterostilbene attenuates mantle cell lymphoma progression

Mantle cell lymphoma (MCL) is an aggressive and mostly incurable B-cell malignancy with frequent relapses after an initial response to standard chemotherapy. Therefore, novel therapies are urgently required to improve MCL clinical outcomes. In this study, MCL cell lines were treated with pterostilbene (PTE), a non-toxic natural phenolic compound primarily found in blueberries. The antitumor activity of PTE was examined by using the Cell Counting Kit-8, apoptosis assays, cell cycle analysis, JC-1 mitochondrial membrane potential assay, western blot analysis, and tumor xenograft models. PTE treatment induced a dose-dependent inhibition of cell proliferation, including the induction of cell apoptosis and cell cycle arrest at the G0/G1 phase. Moreover, the PI3K/Akt/mTOR pathway was downregulated after PTE treatment, which might account for the anti-MCL effects of PTE. Synergistic cytotoxicity was also observed, both in MCL cells and in xenograft mouse models, when PTE was administered in combination with bortezomib (BTZ). The antitumor effects of PTE shown in our study provide an innovative option for MCL patients with poor responses to standardized therapy. It is noteworthy that the treatment combining PTE with BTZ warrants clinical investigation, which may offer an alternative and effective MCL treatment in the future.

Chimeric antigen receptor T cell therapy for non-Hodgkin lymphoma

Non-Hodgkin Lymphoma (NHL) is the most common hematologic malignancy. More than 20,000 people in United States, more than 37,000 people in Europe and more than 199,000 people worldwide die of NHL every year. Recent advances in immunotherapeutic approaches for cancer have resulted in development of new classes of very effective immunotherapeutic approaches including chimeric antigen receptor T (CAR-T) cell therapy that are designed to bypass cancer immune evasion. Here, we review recent advances in CAR-T cell therapy for NHL. US food and drug administration (FDA) recently approved axicabtagene ciloleucel (Yescarta) a CD19 CAR T cell therapy for treatment of relapsed refractory diffuse large B cell lymphoma (DLBCL), high grade lymphoma, and primary mediastinal B cell lymphoma (PMBCL). Approval of Yescarta and rapid development of other CAR T cell therapies at various stages of development are opening up the door for a new wave of CAR T cell therapies that will dramatically change the way we treat NHL and hopefully other malignancies in the near future.

Venetoclax: A new wave in hematooncology

Inhibitors of antiapoptotic proteins of the BCL2 family can successfully restart the deregulated process of apoptosis in malignant cells. Whereas nonselective agents have been limited by their affinity to different BCL2 members, thus inducing excessive toxicity, the highly selective BCL2 inhibitor venetoclax (ABT-199, Venclexta™) has an acceptable safety profile. To date, it has been approved in monotherapy for the treatment of relapsed or refractory chronic lymphocytic leukemia (CLL) with 17p deletion. Extension of indications can be expected in monotherapy and in combination regimens. Sensitivity to venetoclax is not common in lymphomas, but promising outcomes have been achieved in the mantle cell lymphoma group. Venetoclax is also active in multiple myeloma patients, especially in those with translocation t(11;14), even if high-risk features such as del17p are also present. Surprisingly, positive results are being obtained in elderly acute myeloid leukemia patients, in whom inhibition of BCL2 is able to substantially increase the efficacy of low-dose cytarabine or hypomethylating agents. Here, we provide a summary of available results from clinical trials and describe a specific mechanism of action that stands behind the efficacy of venetoclax in hematological malignancies.

A B-cell receptor-related gene signature predicts survival in mantle cell lymphoma: results from the Fondazione Italiana Linfomi MCL-0208 trial

Mantle cell lymphoma patients have variable clinical courses, ranging from indolent cases that do not require immediate treatment to aggressive, rapidly progressing diseases. Thus, diagnostic tools capable of stratifying patients according to their risk of relapse and death are needed. This study included 83 samples from the Fondazione Italiana Linfomi MCL-0208 clinical trial. Through gene expression profiling and quantitative real-time PCR we analyzed 46 peripheral blood and 43 formalin-fixed paraffin-embedded lymph node samples. A prediction model to classify patients was developed. By analyzing the transcriptome of 27 peripheral blood samples, two subgroups characterized by a differential expression of genes from the B-cell receptor pathway (B-cell receptor^low and B-cell receptor^high) were identified. The prediction model based on the quantitative real-time PCR values of six representative genes (AKT3, BCL2, BTK, CD79B, PIK3CD, and SYK), was used to classify the 83 cases (43 B-cell receptor^low and 40 B-cell receptor^high). The B-cell receptor^high signature associated with shorter progression-free survival (P=0.0074), selected the mantle cell lymphoma subgroup with the shortest progression-free survival and overall survival (P=0.0014 and P=0.029, respectively) in combination with high (>30%) Ki-67 staining, and was an independent predictor of short progression- free survival along with the Mantle Cell Lymphoma International Prognostic Index-combined score. Moreover, the clinical impact of the 6- gene signature related to the B-cell receptor pathway identified a mantle cell lymphoma subset with shorter progression-free survival intervals also in an external independent mantle cell lymphoma cohort homogenously treated with different schedules. In conclusion, this 6-gene signature associates with a poor clinical response in the context of the MCL- 0208 clinical trial. (clinicaltrials.gov identifier: 02354313).

Long-term analysis of phase II studies of single-agent lenalidomide in relapsed/refractory mantle cell lymphoma

Mantle cell lymphoma (MCL) is a type of non-Hodgkin lymphoma (NHL) with aggressive disease characteristics resulting in multiple relapses after initial treatment. Lenalidomide is an immunomodulatory agent approved in the US for patients with relapsed/refractory MCL following bortezomib based on results from 3 multicenter phase II studies (2 including relapsed/refractory aggressive NHL and 1 focusing on MCL post-bortezomib). The purpose of this report is to provide longer follow-up on the MCL-001 study (follow-ups were 6.8 [NHL-002], 7.6 [NHL-003], and 52.2 [MCL-001] months). The 206 relapsed MCL patients treated with single-agent lenalidomide (25 mg/day PO, days 1 to 21 every 28-days) had a median age of 67 years (63% ≥65 years), 91% with stage III/IV disease, and 50% with ≥4 previous treatment regimens. With a median follow-up of X, the combined best overall response rate (ORR) was 33% (including 11% with complete remission [CR]/CR unconfirmed CRu). Lenalidomide produced rapid and durable responses with a median time to response of 2.2 months and median duration of response (DOR) of 16.6 months (95% CI: 11.1%-29.8%). The safety profile was consistent and manageable; myelosuppression was the most common adverse event (AE). Overall, single-agent lenalidomide showed consistent efficacy and safety in multiple phase II studies of heavily pretreated patients with relapsed/refractory MCL, including those previously treated with bortezomib.

Mantle cell lymphoma: 2017 update on diagnosis, risk-stratification, and clinical management

DISEASE OVERVIEW

Mantle cell lymphoma (MCL) is a non-Hodgkin lymphoma characterized by involvement of the lymph nodes, spleen, blood and bone marrow with a short remission duration to standard therapies and a median overall survival (OS) of 4-5 years.

DIAGNOSIS

Diagnosis is based on lymph node, bone marrow, or tissue morphology of centrocytic lymphocytes, small cell type, or blastoid variant cells. A chromosomal translocation t (11:14) is the molecular hallmark of MCL, resulting in the overexpression of cyclin D1. Cyclin D1 is detected by immunohistochemistry in 98% of cases. The absence of SOX-11 or a low Ki-67 may correlate with a more indolent form of MCL. The differential diagnosis of MCL includes small lymphocytic lymphoma, marginal zone lymphoma, and follicular lymphoma.

RISK STRATIFICATION

The MCL International Prognostic Index (MIPI) is the prognostic model most often used and incorporates ECOG performance status, age, leukocyte count, and lactic dehydrogenase. A modification of the MIPI also adds the Ki-67 proliferative index if available. The median OS for the low-risk group was not reached (5-year OS of 60%). The median OS for the intermediate risk group was 51 months and 29 months for the high risk group.

RISK-ADAPTED THERAPY

For selected indolent, low MIPI MCL patients, initial observation may be appropriate therapy. For younger patients with intermediate or high risk MIPI MCL, aggressive therapy with a cytotoxic Regimen followed by autologous stem cell transplantation should be considered. Rituximab maintenance after autologous stem cell transplantation has also improved the progression-free and overall survival. For older symptomatic MCL patients with intermediate or high risk MIPI, combination chemotherapy with R-CHOP, R-Bendamustine, or a clinical trial should be considered. In addition, rituximab maintenance therapy may prolong the progression-free survival. At the time of relapse, agents directed at activated pathways in MCL cells such as bortezomib (NFkB inhibitor), lenalidamide (anti-angiogenesis) and Ibruitinib (Bruton's Tyrosine Kinase [BTK] inhibitor) have demonstrated excellent clinical activity in MCL patients. Autologous or allogeneic stem cell transplantation can also be considered in young patients. Clinical trials with novel agents are always a consideration for MCL patients.

What is the optimal initial management of the older MCL patient?

The current first line treatment of a patient with mantle cell lymphoma (MCL) is often considered as too toxic for elderly patients. The elderly, however, comprise the majority of the patients with MCL. The results of several recent studies have shown that the outcome of this patient group is not as dismal as in the past. Indeed, if patients are not considered frail, and can tolerate rituximab and moderate intensive chemotherapy such as R-CHOP followed by rituximab maintenance or R-bendamustine, a 4-year overall survival of >80% can be achieved. In this chapter the developments of the regimens, resulting in the standard treatment options for these patients, are discussed.

Extensive colorectal lymphomatous polyposis complicated by acute intestinal obstruction: a case report

Background

Multiple lymphomatous polyposis is a rare type of gastrointestinal lymphoma that extensively infiltrates the intestine. Multiple lymphomatous polyposis originates from the mantle zone of the lymphoma follicle and is considered to be a mantle cell lymphoma, which is a relatively aggressive type of B-cell non-Hodgkin’s lymphoma. We report an unusual case of a patient with multiple lymphomatous polyposis with extensive colorectal involvement and acute intestinal obstruction, an atypical complication of this rare disease. On the basis of this case study, the pitfalls in gastrointestinal tract lymphomatous polyposis diagnosis and prognosis, as well as the treatment options, are discussed.

Case presentation

Our patient was a 76-year-old white woman with asthenia, cramps, and swelling in the lower left quadrant of the abdomen, as well as weight loss within the previous 5 months. A colonoscopy revealed polyps in the rectum, sigmoid colon, descending colon, and right and left colic flexures. A biopsy revealed lymphomatous infiltration of the intestinal wall. Because of the large size of the polypoid masses, which narrowed the colonic lumen in multiple locations, the patient developed acute intestinal obstruction and was referred for laparotomy. She underwent a total proctocolectomy with a permanent ileostomy and a left salpingo-oophorectomy. Microscopic examination showed the presence of a multicentric, low-grade, small lymphocytic lymphoma. Immunohistochemical analysis revealed positive immunostaining for CD79a, CD20, and CD45. These results were consistent with the diagnosis of mantle cell lymphoma. Two weeks after surgery and prior to discharge, but before the beginning of chemotherapy, the patient’s general condition worsened as she experienced a severe and progressive respiratory tract infection, advanced respiratory insufficiency, and septic shock, and she ultimately died.

Conclusions

Mantle cell lymphoma develops as a progressive and aggressive disease with widespread polyposis of the gastrointestinal tract. The intensive chemotherapeutic regimens usually result in the regression of macroscopic and microscopic lesions; however, remissions are short in duration, and the median length of patient survival is 3–4 years. Mantle cell lymphoma is a rare disease that should be part of the differential diagnosis of polypoid diseases of the large intestine.

Results from the Belgian mantle cell lymphoma registry

INTRODUCTION

Mantle cell lymphoma is a B-cell non-Hodgkin's lymphoma characterized by a t(11;14), resulting in overexpression of cyclin D1. Conventional chemotherapy obtains frequent (but short) remissions, leading to a poor median overall survival (OS) of 3-5 years. To obtain more information about the prevalence and current treatment of Mantle cell lymphoma (MCL) in Belgium, we collected data in a Belgian registry of MCL.

MATERIALS AND METHODS

All Belgian MCL patients, t(11;14) and/or cyclin D1 positive, seen in hematology departments over a one-year period (April 2013-March 2014) were included. Data about patient characteristics, histology, treatment lines, and response were compiled and retrospectively analyzed.

RESULTS

Four hundred and four patients were included with a median age at diagnosis of 64 years (range 23-96 years) and a male predominance (72%). For 2013, we calculated a prevalence of at least 36.2 per million and an incidence of at least 7.0 per million in the Belgian population. Characteristics at diagnosis involved lymphadenopathy (82%), splenomegaly (44%), B-symptoms (39%), and hepatomegaly (10%). Bone marrow invasion was present at diagnosis in 77%. Stage at diagnosis was advanced in the majority of cases. The median number of treatment lines was 1. Type of first line treatment included a combination of anthracyclin and cytarabine-based regimen (34%), anthracyclin (39%), and other. Rituximab was used in 88% of first line treatments. In 44% first line treatment was followed by autologous stem cell transplantation.

CONCLUSION

The analysis of this Belgian MCL registry provides insight in the epidemiology, demographics, and current treatment of our Belgian MCL population.

Hyperfractionated Cyclophosphamide, Vincristine, Doxorubicin, and Dexamethasone Chemotherapy in Mantle Cell Lymphoma Patients Is Associated with Higher Rates of Hematopoietic Progenitor Cell Mobilization Failure despite Plerixafor Rescue

Induction regimens for mantle cell lymphoma (MCL) can be categorized into highly intensive regimens containing cytarabine and less intense regimens, such as rituximab, cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone (R-CHOP) or rituximab with bendamustine (R-bendamustine). Prior publications have shown rituximab and hyperfractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone (R-hyperCVAD) can be associated with stem cell mobilization failures. However, those studies did not include the use of plerixafor as rescue for stem cell mobilization failure. We examined our database of 181 consecutive MCL patients who received upfront therapy from 2005 to 2015 with either R-hyperCVAD or less intense chemotherapy (R-bendamustine and R-CHOP only) regimens to assess impact of frontline chemotherapy on collection of hematopoietic cell progenitors before autologous stem cell transplantation (ASCT). In the preplerixafor era (before August 16, 2009), a significant difference in peripheral blood stem cell (PBSC) collection failure between the R-hyperCVAD (12%) and other chemotherapy (11%) groups was not established. However, in the postplerixafor era, use of R-hyperCVAD chemotherapy was associated with significantly higher rates of hematopoietic progenitor cell collection failures (17%) compared with that observed in the other chemotherapy group (4%; P = .04). The rates of mobilization failure declined to 4% in the postplerixafor era from 11% in the preplerixafor era for patients receiving less intensive chemotherapy. Conversely, the rate of mobilization failure increased in the R-hyperCVAD group from 12% in the preplerixafor era to 17% in the postplerixafor era. Plerixafor does not overcome the negative impact of R-hyperCVAD on PBSC mobilization, and caution is warranted in using R-hyperCVAD in patients with newly diagnosed MCL who are candidates for ASCT.

Primary bone mantle cell lymphomas with multiple vertebral compression fractures: A case report

Mantle cell lymphoma (MCL) is a mature B-cell non-Hodgkin lymphoma. Patients with MCL generally present with extensive lymphadenopathy and extranodal involvement. To the best of our knowledge, no cases of primary bone MCL with multiple vertebral compression fractures have been reported in the literature thus far. The current study reports the case of a 75-year-old Chinese male patient presenting with lower back pain for 1 year. B symptoms were not observed in the patient's medical history. X-ray revealed osteoporosis, and mixed osteolytic and osteosclerotic lesions in the T10 and L1 vertebrae with decreased height. Computed tomography of the spine showed multiple vertebral compression fractures, particularly at T10 and L1. Furthermore, magnetic resonance imaging demonstrated a diffuse homogeneous abnormal signal with multiple vertebral compression fractures. The patient underwent vertebral biopsy and percutaneous balloon kyphoplasty. Histopathological examination of the biopsy revealed abnormal, diffuse, atypical, small-sized, slightly irregular lymphocytes with condensed chromatin. Immunohistochemical staining showed CD5⁺, CD20⁺ and cyclin D1⁺. Thus, the patient was diagnosed with primary bone MCLs and chemotherapy was administered. During the 2-month follow-up, the patient remained in a good clinical condition. The present study reports a rare case of primary osseous MCL and a review of the literature.

The molecular pathogenesis of mantle cell lymphoma

Mantle cell lymphoma (MCL) is characterized by the translocation t(11;14) leading to constitutive cyclin D1 overexpression. However, overexpression of cyclin D1 alone is insufficient to cause malignant transformation. Secondary genetic alterations and deregulated signaling pathways involved in DNA damage response, cell proliferation, and apoptosis are indispensable for MCL lymphomagenesis. Recent studies investigating the biology of MCL have revealed crucial importance of B-cell receptor (BCR), nuclear factor-kappa B (NF-κB), phosphoinositide 3-kinase (PI3K), and BCL2 signaling for the molecular pathogenesis of MCL. In addition, activation of the Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3), NOTCH and WNT pathway can be observed in subsets of MCLs. These addictions can potentially be utilized therapeutically by implementing small molecule inhibitors into current treatment regimens.

Efficacy and safety of ibrutinib in Japanese patients with relapsed or refractory mantle cell lymphoma

In this multicenter, single‐arm, phase II study, the efficacy and safety of ibrutinib were examined in Japanese patients with relapsed or refractory mantle cell lymphoma (MCL). Patients (age ≥20 years) with relapsed or refractory MCL who had progressed after receiving at least one prior treatment regimen, were enrolled. Patients were treated with oral ibrutinib (560 mg once daily; 28‐day cycle) until disease progression (or relapse), unacceptable toxicity, or study end. The primary end‐point was overall response rate. Secondary end‐points included duration of response (DOR), time to response, progression‐free survival (PFS), overall survival, and safety. Of the 16 patients who received treatment, 5 patients discontinued the study (progressive disease, 4; sepsis, 1). Median duration of ibrutinib exposure was 6.5 months (range, 2.8–8.3 months). The overall response rate was 87.5% (90% confidence interval, 65.6–97.7; complete response = 2 [12.5%]; partial response = 12 [75.0%]). Median time to response for all responders (n = 14) was 1.8 months (range, 0.7–5.3 months). The median DOR and PFS were not estimable due to censoring (range: DOR, 1.1–6.4+ months; PFS, 2.8–8.0+ months). Overall survival data were immature due to the limited observation period. A total of 8/16 patients (50%) had at least one grade 3 adverse event (AE), and 5 (31.3%) patients reported serious AEs. The most commonly reported AEs were diarrhea and stomatitis (37.5% each), platelet count decrease (31.3%), and anemia (25%). Overall, orally administered single agent ibrutinib was efficacious with an acceptable safety profile in Japanese patients with relapsed or refractory MCL. Clinical trial registration NCT02169180 (ClinicalTrials.gov).

Is there a role for a maintenance rituximab in indolent lymphoproliferative diseases other than follicular lymphoma?

Rituximab (R) is an anti-CD20 monoclonal antibody which has become an essential component for the treatment of B-cell lymphomas. When associated to chemotherapy it improves the outcome of the patients with diffuse large B-cell lymphoma, follicular lymphoma, and other lymphoproliferative diseases in comparison to chemotherapy alone. For patients with newly diagnosed follicular lymphoma achieving at least a partial response to initial immuno-chemotherapy, maintenance R was associated with an improvement in progression-free survival and a meta-analysis of randomized maintenance trials suggests an overall survival advantage. The role of maintenance R in other indolent diseases is less well-defined. In this article, we summarize the data available for this strategy in less frequent subtypes of indolent B-cell lymphomas.

Cutaneous mantle cell lymphoma: a clinicopathologic review of 10 cases

Cutaneous mantle cell lymphoma (MCL) is exceedingly rare, almost always occurring as a dissemination of systemic MCL. To date, only 32 cases have been described. We report a series of 10 cases of MCL in the skin, and provide a comprehensive clinicopathologic review with clinical follow-up. Our cases occurred in older individuals (mean age = 70) and were more frequently in men (90%). Half of them presented in the head and neck region as a mass/nodule, and the remainder in the trunk and extremities as nodules. All patients have stage IV disease. In two of the 10 cases (20%) the cutaneous lesions preceded the diagnosis of disseminated disease. In two of the seven cases with available clinical follow-up information (33%) the skin was immediately involved after the diagnosis of MCL, and in three of the seven the skin was the first site of recurrence (mean interval = 57 months). The mean time to recurrence of the disease was 45.4 months and the overall survival was 66.3 months. Histologically six out of 10 cases (60%) had either pleomorphic or blastoid morphology (four out of 10 and two out of 10, respectively). The mean number of mitoses per 10 high-power fields was 18.44. While nine out of 10 cases expressed cyclin-D1, one case was not positive for cyclin-D1 but did label with SOX-11. Limited cytogenetic data showed trisomy 14 in one case, in addition to the t(11;14) translocation.

Characterization of a mantle cell lymphoma cell line resistant to the Chk1 inhibitor PF-00477736

Mantle cell lymphoma (MCL) is an aggressive B-cell lymphoma characterized by the chromosomal translocation t(11;14) that leads to constitutive expression of cyclin D1, a master regulator of the G1-S phase. Chk1 inhibitors have been recently shown to be strongly effective as single agents in MCL. To investigate molecular mechanisms at the basis of Chk1 inhibitor activity, a MCL cell line resistant to the Chk1 inhibitor PF-00477736 (JEKO-1 R) was obtained and characterized. The JEKO-1 R cell line was cross resistant to another Chk1 inhibitor (AZD-7762) and to the Wee1 inhibitor MK-1775. It displayed a shorter doubling time than parental cell line, likely due to a faster S phase. Cyclin D1 expression levels were decreased in resistant cell line and its re-overexpression partially re-established PF-00477736 sensitivity. Gene expression profiling showed an enrichment in gene sets involved in pro-survival pathways in JEKO-1 R. Dasatinib treatment partly restored PF-00477736 sensitivity in resistant cells suggesting that the pharmacological interference of pro-survival pathways can overcome the resistance to Chk1 inhibitors. These data further corroborate the involvement of the t(11;14) in cellular sensitivity to Chk1 inhibitors, fostering the clinical testing of Chk1 inhibitors as single agents in MCL.

Endobronchial involvement of mantle cell lymphoma: A case report

Mantle cell lymphoma (MCL) is a subtype of B-cell non-Hodgkin's lymphoma. Most cases of MCL have extranodal involvement at the time of the initial diagnosis; however, endobronchial involvement is rare. An 87-year-old man was referred to our hospital because of dyspnea on exertion. A chest CT revealed diffuse irregular wall thickening of the trachea and bilateral bronchi. A bronchoscopy revealed a diffuse irregular surface of the tracheal and bilateral bronchial mucosa and polyposis-like lesions. He was diagnosed as having MCL based on an endobronchial biopsy, and the diagnosis was confirmed using immunohistochemical staining.