Mantle cell lymphoma: 2013 Update on diagnosis, risk-stratification, and clinical management

Targeting CERS6-AS1/FGFR1 axis as synthetic vulnerability to constrain stromal cells supported proliferation in Mantle cell lymphoma

The interaction between stromal and tumor cells in tumor microenvironment is a crucial factor in Mantle cell lymphoma (MCL) progression and therapy resistance. We have identified a long non-coding RNA, CERS6-AS1, upregulated in MCL and associated with poor overall survival. CERS6-AS1 expression was elevated in primary MCL within stromal microenvironment and in a subset of MCL cells adhered to stromal layer. These stromal-adhered MCL-subsets exhibited cancer stem cell signatures than suspension counterparts. Mechanistically, we found that downregulating CERS6-AS1 in MCL reduced Fibroblast Growth Factor Receptor-1 (FGFR1), expression attributed to loss of its interaction with RNA-binding protein nucleolin. In addition, using in-silico approach, we have discovered a direct interaction between nucleolin and 5'UTR of FGFR1, thereby regulating FGFR1 transcript stability. We discovered a positive association of CERS6-AS1 with cancer stem cell signatures, and Wnt signaling. Building on these, we explored potential therapeutic strategies where combining nucleolin-targeting agent with FGFR1 inhibition significantly contributed to reversing cancer stem cell signatures and abrogated primary MCL cell growth on stromal layer. These findings provide mechanistic insights into regulatory network involving CERS6-AS1, nucleolin, and FGFR1 axis-associated crosstalk between tumor cells and stromal cell interaction and highlights therapeutic potential of targeting a non-coding RNA in MCL.

A nodular type of mantle cell lymphoma in the nasopharynx

Mantle cell lymphoma (MCL) is a subtype of B-cell lymphoma derived from CD5-positive antigen-naïve pre-germinal center B-cells within the mantle zone that surrounds normal germinal center follicles. MCL comprises approximately 5 to 10% of all lymphomas. Tonsil is the most common location of MCL in the head and neck region, followed by the nasopharynx. Primary MCL involving the nasopharynx is extremely rare. Its clinical course is very aggressive with frequent relapses after conventional chemotherapy. It always presents as a protruding mass on the mucosal lining of the pharyngeal cavity. Here, we report a new nodular type of MCL in the nasopharynx. Endoscopically, this case showed multiple nodular lesions of primary MCL on the nasopharyngeal mucosa. This unique finding has not been reported yet in the English literature. These lesions should be differentiated from simple pharyngeal infections or benign lymphoid hyperplasia in the nasopharynx.

Exploiting the fibroblast growth factor receptor-1 vulnerability to therapeutically restrict the MYC-EZH2-CDKN1C axis-driven proliferation in Mantle cell lymphoma

Mantle cell lymphoma (MCL) is a lethal hematological malignancy with a median survival of 4 years. Its lethality is mainly attributed to a limited understanding of clinical tumor progression and resistance to current therapeutic regimes. Intrinsic, prolonged drug treatment and tumor-microenvironment (TME) facilitated factors impart pro-tumorigenic and drug-insensitivity properties to MCL cells. Hence, elucidating neoteric pharmacotherapeutic molecular targets involved in MCL progression utilizing a global "unified" analysis for improved disease prevention is an earnest need. Using integrated transcriptomic analyses in MCL patients, we identified a Fibroblast Growth Factor Receptor-1 (FGFR1), and analyses of MCL patient samples showed that high FGFR1 expression was associated with shorter overall survival in MCL patient cohorts. Functional studies using pharmacological intervention and loss of function identify a novel MYC-EZH2-CDKN1C axis-driven proliferation in MCL. Further, pharmacological targeting with erdafitinib, a selective small molecule targeting FGFRs, induced cell-cycle arrest and cell death in-vitro, inhibited tumor progression, and improved overall survival in-vivo. We performed extensive pre-clinical assessments in multiple in-vivo model systems to confirm the therapeutic potential of erdafitinib in MCL and demonstrated FGFR1 as a viable therapeutic target in MCL.

Tackling Mantle Cell Lymphoma in Europe

An expert panel convened by the European Alliance for Personalized Medicine (EAPM) reflected on achievements and outstanding challenges in Europe in mantle cell lymphoma (MCL). Through the prism of member state experience, the panel noted advances in outcomes over the last decade, but highlighted issues constituting barriers to better care. The list notably included availability of newer treatments, infrastructure and funding for related testing, and shortages of relevant skills and of research support. The prospect of improvements was held to reside in closer coordination and cooperation within and between individual countries, and in changes in policy and scale of investment at both national and EU levels.

Durable remission with Bruton's tyrosine kinase inhibitor therapy in a patient with leptomeningeal disease secondary to relapsed mantle cell lymphoma

Mantle cell lymphoma (MCL) is an incurable B cell non-Hodgkin's lymphoma with a variable clinical course. Central nervous system (CNS) involvement is a rare and dreaded complication in MCL. We report a case of leptomeningeal relapse of MCL that was successfully treated with a single-agent Bruton's tyrosine kinase inhibitor. A man in his 50s with MCL was treated with six cycles of bendamustine-rituximab, achieving a complete remission (CR) and was subsequently placed on rituximab maintenance for 2 years. Four years later, he was hospitalised with symptoms of organic brain syndrome. Brain MRI and cerebrospinal fluid analysis confirmed CNS relapse of MCL. He was treated with dexamethasone, ibrutinib 560 mg/day and intrathecal cytarabine with improvement in neurological symptoms, and a follow-up MRI showed CR. The patient was later switched to acalabrutinib due to intolerance to ibrutinib. The patient is tolerating this regimen well, remaining in CR 3 years later.

Association between miR-212-3p and SOX11, and the effects of miR-212-3p on cell proliferation and migration in mantle cell lymphoma

To the best of our knowledge, the effect of miR-212-3p on sex-determining region Y-box 11 (SOX11) expression has not been previously investigated and how this effect affects cell proliferation and migration in lymphoma remains unclear. The present study aimed to assess the association between microRNA-212-3p (miR-212-3p) and SOX11, and the effects of miR-212-3p on cell proliferation and migration in mantle cell lymphoma. Cancer tissue and corresponding paracancerous tissue samples were collected from 65 patients with mantle cell lymphoma. The mRNA expression levels of miR-212-3p and SOX11 were analyzed using quantitative PCR, and SOX11 protein expression was determined using western blotting. Following transfection, the miR-212-3p mimic group exhibited a significantly lower SOX11 mRNA and protein expression than the miR-NC group. After 48–72 h of transfection, cell proliferation in the miR-212-3p mimic group was significantly lower than that in the miR-NC group. Furthermore, the miR-212-3p mimic group exhibited significantly lower cell invasion and significantly higher apoptosis than the miR-NC group. The current results suggested that miR-212-3p inhibited lymphoma cell proliferation and migration, and promoted their apoptosis by specifically regulating SOX11. Therefore, miR-212-3p may serve as a novel therapeutic target and marker for lymphoma.

Bilateral mantle cell lymphoma of the ciliary body that responded to a combined local radiotherapy and chemotherapy regimen: a case report

BACKGROUND

Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) that often affects men over the age of 60. Systemic metastasis of MCL to eyes is rare and intraocular involvement is even rarer, which usually affects the choroid and iris. To the best of our knowledge, ciliary body metastasis of systemic MCL has not been reported.

CASE PRESENTATION

A 59-year-old Han Chinese male with past-history of systemic MCL complained of redness, pain and blurred vision in the left eye. Ocular examination revealed a normal appearance in the right eye, and conjunctival injection, pseudohypopyon and anterior protrusion of peripheral iris in the left eye, all of which were unresponsive to corticosteroid treatments. Ultrasound biomicroscopy (UBM) and B-scan were then performed which detected ciliary body masses in both eyes with no vitreous and retino-choroidal anomalies. Combined liquid-based cytology tests and gene rearrangement assays of the aqueous humor specimen confirmed this to be a B-cell malignancy. Then both eyes were treated with external beam irradiation (40 Gy, delivered evenly in twenty fractions) over a course of one month. Additionally, the left eye received intravitreal methotrexate (MTX) (weekly for the first month, every two weeks for the second month, and monthly thereafter) over a course of twelve months. This therapy eventually led to complete remission of all symptoms in one month and disappearance of the ciliary body masses in twelve months.

CONCLUSION

Here we first reported a case of bilateral ciliary body MCL infiltration which was diagnosed by combined liguid-based cytology and gene rearrangement of aqueous humor cells. UBM may serve as a valuable tool in the diagnosis and serial assessments of anterior segment tumors.

The effect of high-dose cytarabine followed by autologous hematopoietic stem cell transplantation on the outcome of patients with mantle cell lymphoma

INTRODUCTION

The aim of this study was to investigate the influence of high-dose cytosine arabinoside (HDAC)-containing treatments followed by autologous hematopoietic stem cell transplantation on the survival of patients with mantle cell lymphoma.

MATERIAL AND METHODS

The data of 27 MCL patients who were followed-up between January 2009 and December 2015 were analyzed retrospectively.

RESULTS

The median age of the patients was 63 (range, 45-82) with 22 (81.4%) males and 5 (18.6%) females. Eight of 27 patients were treated with HDAC-containing regimens either as induction or salvage chemotherapy followed by autologous hematopoietic stem cell transplantation (AHSCT). The patients who received HDAC-containing regimen followed by AHSCT were found to have better one-year survival compared to others (p = 0.03). Median follow-up of patient cohort was 27.6 months and median overall survival (OS) was not reached. The probability of one-year OS for all patients was 76.8%.

CONCLUSION

Our findings suggest that HDAC treatment followed by AHSCT seems to provide the best outcome for young-fit patients presenting with mantle cell lymphoma.

Pleomorphic Mantle Cell Lymphoma of the Tongue Base Presenting With Dysphagia

Objectives

We aim to increase awareness of pleomorphic mantle cell lymphoma as a rare, but aggressive form of lymphoma with propensity for recurrence in secondary locations.

Methods

We report the case of a 70-year-old man who presented with chronic post-nasal drainage, dysphagia, and voice changes caused by a tongue base mass.

Results

Partial excision and pathology showed a pleomorphic mantle cell lymphoma, and radiation treatment was completed. A regional recurrence was detected 3 years later and treated with radiation. He had no evidence of disease 17 months after treatment of the recurrence and is under close surveillance.

Conclusions

Pleomorphic mantle cell lymphoma is an aggressive subtype of non-Hodgkin lymphoma that can affect the head and neck. Confirming the diagnosis with immunotyping and genotyping from fresh specimens can guide appropriate treatment and then close clinical follow-up.

Abnormal microRNA expression in the course of hematological malignancies

Research on the carcinogenesis process is currently focused primarily on understanding its genetic basis and molecular abnormalities that may be predictive factors and therapeutic targets. It was clearly confirmed recently that microRNAs are involved in the mechanisms of leukocyte development, differentiation, and apoptosis, as well as in the pathogenesis of proliferative diseases of the hematopoietic system. Currently, research strategies allow determination of the deregulation of microRNA profiles in relation to other cytogenetic aberrations, as well as prognostic factors and primary end points. The problem of the possibility of their use as therapeutic targets is also increasingly discussed. In this article, we analyze literature data on abnormalities in microRNA expression in proliferative diseases of the hematopoietic system in the context of classic cytogenetic and molecular aberrations.

Bortezomib-based therapy for transplant-ineligible East Asian patients with newly diagnosed mantle-cell lymphoma

Introduction

This subgroup analysis of the LYM-3002 Phase III study (NCT00722137) investigated whether substituting bortezomib for vincristine in frontline R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) therapy could improve outcomes in East Asian patients with newly diagnosed mantle-cell lymphoma (MCL).

Materials and methods

A total of 121 East Asian patients from China, Taiwan, Japan, and the Republic of Korea with stage II–IV MCL who were ineligible or not considered for stem-cell transplantation were enrolled to six to eight 21-day cycles of R-CHOP or VR-CAP (R-CHOP with bortezomib replacing vincristine).

Results

The primary end point was progression-free survival. After a median follow-up of 42.4 months, median progression-free survival in East Asian patients was 13.9 (R-CHOP) versus 28.6 (VR-CAP) months (HR 0.7, P=0.157; 43% improvement with VR-CAP). Secondary end points (R-CHOP vs VR-CAP), including complete response rate (47% vs 63%), duration of complete response (median 16.6 vs 46.7 months), and treatment-free interval (median 21 vs 46.5 months), were improved with VR-CAP. VR-CAP was associated with increased but manageable toxicity. The most frequent adverse events were hematologic toxicities.

Conclusion

VR-CAP was effective in East Asian patients with newly diagnosed MCL, and could be considered for patients in whom stem-cell transplantation is not an option.

Oncogenic c-terminal cyclin D1 (CCND1) mutations are enriched in endometrioid endometrial adenocarcinomas

Cyclin D1 (CCND1) is a core cell cycle regulator and is frequently overexpressed in human cancers, often via amplification, translocation or post-transcription regulation. Accumulating evidence suggests that mutations of the CCND1 gene that result in nuclear retention and constitutive activation of CDK4/6 kinases are oncogenic drivers in cancer. However, the spectrum of CCND1 mutations across human cancers has not been systematically investigated. Here, we retrospectively mined whole-exome sequencing data from 124 published studies representing up to 29,432 cases from diverse cancer types and sites of origin, including carcinoma, melanoma, sarcoma and lymphoma/leukemia, via online tools to determine the frequency and spectrum of CCND1 mutations in human cancers and their associated clinico-pathological characteristics. Overall, in contrast to gene amplification, which occurred at a frequency of 4.8% (1,419 of 28,769 cases), CCND1 mutations were of very low frequency (0.5%, 151 of 29,432 cases) across all cancers, but were predominantly enriched in uterine endometrioid-type adenocarcinoma (6.5%, 30 of 458 cases) in both primary tumors and in advanced, metastatic endometrial cancer samples. CCND1 mutations in endometrial endometrioid adenocarcinoma occurred most commonly in the c-terminus of cyclin D1, as putative driver mutations, in a region thought to result in oncogenic activation of cyclin D1 via inhibition of Thr-286 phosphorylation and nuclear export, thereby resulting in nuclear retention and protein overexpression. Our findings implicate oncogenic c-terminal mutations of CCND1 in the pathogenesis of a subset of human cancers and provide a key resource to guide future preclinical and clinical investigations.

Mantle cell lymphoma presenting as bilateral adrenal huge masses

We present a middle-aged woman complaining of weakness, lethargy and weight loss for 6 months. Positron emission tomography (PET)/CT scan revealed huge bilateral adrenal masses with intense 18F-fluorodeoxyglucose avidity. Biopsy and immunohistochemical staining were compatible with mantle cell lymphoma (MCL). The patient received six cycles of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) followed by four cycles of intrathechal methotrexate chemotherapy. Bone marrow aspiration biopsy was performed for initial staging and also before bone marrow transplantation. Follow-up PET/CT scan after completion of chemotherapy and before bone marrow transplantation demonstrated complete metabolic response with no evidence of abnormal metabolic activity in either adrenal gland or bone marrow. MCL has an aggressive nature and is usually considered incurable; however, there have been a few reports indicating favourable treatment response when MCL is rarely arising from the adrenal glands. Dramatic response of a primary adrenal MCL to R-CHOP is documented in this case.

Genetic heterogeneity in primary and relapsed mantle cell lymphomas: Impact of recurrent CARD11 mutations

The genetic mechanisms underlying disease progression, relapse and therapy resistance in mantle cell lymphoma (MCL) remain largely unknown. Whole-exome sequencing was performed in 27 MCL samples from 13 patients, representing the largest analyzed series of consecutive biopsies obtained at diagnosis and/or relapse for this type of lymphoma. Eighteen genes were found to be recurrently mutated in these samples, including known (ATM, MEF2B and MLL2) and novel mutation targets (S1PR1 and CARD11). CARD11, a scaffold protein required for B-cell receptor (BCR)-induced NF-κB activation, was subsequently screened in an additional 173 MCL samples and mutations were observed in 5.5% of cases. Based on in vitro cell line-based experiments, overexpression of CARD11 mutants were demonstrated to confer resistance to the BCR-inhibitor ibrutinib and NF-κB-inhibitor lenalidomide. Genetic alterations acquired in the relapse samples were found to be largely non-recurrent, in line with the branched evolutionary pattern of clonal evolution observed in most cases. In summary, this study highlights the genetic heterogeneity in MCL, in particular at relapse, and provides for the first time genetic evidence of BCR/NF-κB activation in a subset of MCL.

Efficacy and safety of frontline rituximab, cyclophosphamide, doxorubicin and prednisone plus bortezomib (VR-CAP) or vincristine (R-CHOP) in a subset of newly diagnosed mantle cell lymphoma patients medically eligible for transplantation in the randomized, phase 3 LYM-3002 study

This post-hoc subanalysis of the LYM-3002 phase 3 study assessed the efficacy and safety of substituting vincristine in rituximab, cyclophosphamide, doxorubicin and prednisone (R-CHOP; n = 42) for bortezomib (VR-CAP; n = 38) in a subgroup of 80 mantle cell lymphoma (MCL) patients aged <60 years who did not receive stem cell transplantation (SCT) despite medical eligibility. Complete response (CR)/unconfirmed CR (CRu) rates were 67 vs. 39% (odds ratio 3.69 [95% CI(confidence interval): 1.31, 10.41]; p = .012). After 40 months median follow-up, median progression-free survival by independent radiology committee with VR-CAP vs. R-CHOP was 32.6 vs. 12.0 months (hazard ratio (HR) 0.59 [95% CI: 0.31, 1.13]; p = .108); median overall survival was not reached vs. 47.3 months (HR 0.81 [95% CI: 0.33, 1.96]; p = .634). Adverse events included neutropenia (92/76%), thrombocytopenia (70/10%) and leukopenia (65/50%). VR-CAP represents a potential alternative to R-CHOP in combined and/or alternating regimens for younger, SCT-eligible MCL patients.

Mantle cell lymphoma in the era of precision medicine-diagnosis, biomarkers and therapeutic agents

Despite advances in the development of clinical agents for treating Mantle Cell Lymphoma (MCL), treatment of MCL remains a challenge due to complexity and frequent relapse associated with MCL. The incorporation of conventional and novel diagnostic approaches such as genomic sequencing have helped improve understanding of the pathogenesis of MCL, and have led to development of specific agents targeting signaling pathways that have recently been shown to be involved in MCL. In this review, we first provide a general overview of MCL and then discuss about the role of biomarkers in the pathogenesis, diagnosis, prognosis, and treatment for MCL. We attempt to discuss major biomarkers for MCL and highlight published and ongoing clinical trials in an effort to evaluate the dominant signaling pathways as drugable targets for treating MCL so as to determine the potential combination of drugs for both untreated and relapse/refractory cases. Our analysis indicates that incorporation of biomarkers is crucial for patient stratification and improve diagnosis and predictability of disease outcome thus help us in designing future precision therapies. The evidence indicates that a combination of conventional chemotherapeutic agents and novel drugs designed to target specific dysregulated signaling pathways can provide the effective therapeutic options for both untreated and relapse/refractory MCL.

Mantle Cell Lymphoma Relapsing as Disease of Skin, Orbit and CNS: An Extremely Rare Presentation and a Review of Literature

Mantle cell lymphoma (MCL) is a form of non-Hodgkin’s lymphoma originating from mature B cells. The hallmark gene translocation (11:14) results in overexpression of cyclin D1. Affected extranodal sites include bone marrow and gastrointestinal tract, but skin, orbit or CNS are rarely involved. Twenty-four cases have reported involvement of skin by MCL, while orbital MCL is equally rare. Our case is the first to report relapsed MCL with involvement of the skin and orbit simultaneously without disease in the lymphatic system or the bone marrow. A 53-year-old female with stage IV MCL initially presented with pancytopenia, adenopathy and splenomegaly. She achieved complete remission after six cycles of rituximab and bendamustine. Within 4 weeks of treatment, she developed diplopia and a rash of the left breast. Skin biopsy showed lymphoma infiltrates with B-cell markers for MCL. MRI of the orbits and brain suggested orbital lymphoma. CSF cytology further confirmed MCL cells. At time of relapse, she continued to be in hematologic remission. She initiated intrathecal cytarabine and methotrexate along with ibrutinib. R-CHOP was then added to the regimen. Within 2 weeks of starting treatment, her skin disease resolved and she had improvement in vision. MCL commonly presents as a disseminated disease, resulting in high mortality. Involvement of the skin or orbit has been sparingly reported and always suggests aggressive disease. It thus poses a challenge to diagnose and treat the condition as evidenced by resolution of adenopathy and bone marrow disease. Due to the overall poor prognosis of MCL and its unique presentations, as demonstrated by our case, early detection and prompt treatment are crucial to survival.

ZGDHu-1 promotes apoptosis of mantle cell lymphoma cells

Mantle cell lymphoma (MCL) is a well-defined aggressive Non-Hodgkin-lymphoma with short survival rates and remains incurable to date. Previously, we demonstrated the antitumor activity of ZGDHu-1(N, N'-di-(m-methylphenyi)-3, 6-dimethyl-1, 4-dihydro-1, 2, 4, 5-tetrazine-1, 4-dicarboamide) in chronic lymphocytic leukemia. In this study, ZGDHu-1 shows potent anti-lymphoma activity in MCL cells. ZGDHu-1 significantly induces cell cycle G2/M phase arrest and apoptosis in MCL cells. ZGDHu-1 reduces the protein levels of Mcl-1, Bcl-XL and cyclin D1. Importantly, ZGDHu-1 inhibits TNFα-induced IkBa phosphorylation, p65 nuclear translocation and NF-kB downstream target gene expression in MCL cells. MCL samples expressing high levels of Bcl-2 and high Bcl-2/Bax ratios tend to be less effective to ZGDHu-1. Together, these results suggest that ZGDHu-1 could inhibit the NF-kB signaling pathway partly, which may lead to the suppression of cell proliferation and the induction of apoptosis in MCL cells. Thus, our studies provide evidence of the potential of ZGDHu-1 in treating mantle cell lymphoma.

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.

A case report of mantle cell lymphoma manifesting as a foot lesion

INTRODUCTION

Mantle cell lymphoma (MCL) is a rare B-cell non-Hodgkin lymphoma that most commonly affects men above the age of 60 years. The disease is called MCL because the tumor cells originate from the mantle zone of the lymph node. The most commonly affected sites are the lymph nodes, bone marrow, gastrointestinal tract, Waldeyer's ring and rarely the skin, breast and central nervous system. Only 22 cases with skin manifestation of MCL have been reported so far.

CASE

We report the case of a 73-year-old woman who was diagnosed with MCL and underwent treatment, but later relapsed and presented with an ulcerated mass over her right foot. She underwent 6 cycles of chemotherapy with bendamustine plus rituximab and responded with resolution of the foot lesion.

DISCUSSION AND CONCLUSIONS

MCL is an aggressive lymphoma with a median overall survival of 3-5 years for advanced disease, while early-stage disease has a better prognosis. It rarely involves the skin. Since cutaneous lesions can be the first manifestation of MCL, awareness of this less common presentation is crucial to establish an early diagnosis and pursue treatment as early as possible, as it significantly impacts the survival rate.

Diagnostic and predictive biomarkers for lymphoma diagnosis and treatment in the era of precision medicine

Lymphomas are a group of hematological malignancies derived from lymphocytes. Lymphomas are clinically and biologically heterogeneous and have overlapping diagnostic features. With the advance of new technologies and the application of efficient and feasible detection platforms, an unprecedented number of novel biomarkers have been discovered or are under investigation at the genetic, epigenetic, and protein level as well as the tumor microenvironment. These biomarkers have enabled new clinical and pathological insights into the mechanisms underlying lymphomagenesis and also have facilitated improvements in the diagnostic workup, sub-classification, outcome stratification, and personalized therapy for lymphoma patients. However, integrating these biomarkers into clinical practice effectively and precisely in daily practice is challenging. More in-depth studies are required to further validate these novel biomarkers and to assess other parameters that can affect the reproducibility of these biomarkers such as the selection of detection methods, biological reagents, interpretation of data, and cost efficiency. Despite these challenges, there are many reasons to be optimistic that novel biomarkers will facilitate better algorithms and strategies as we enter a new era of precision medicine to better refine diagnosis, prognostication, and rational treatment design for patients with lymphomas.

Leukemic non-nodal mantle cell lymphomas have a distinct phenotype and are associated with deletion of PARP1 and 13q14

Leukemic non-nodal mantle cell lymphoma (lMCL) is a particular subtype of mantle cell lymphoma (MCL), characterized by leukemic non-nodal disease and slow progression. Recognition of this entity is relevant to avoid overtreatment. Despite indolent clinical behaviour, lMCL might transform to a more aggressive disease. The purpose of this study was to compare lMCL with classical MCL (cMCL) and aggressive MCL (aMCL) using immunohistochemistry, interphase fluorescence in situ hybridization (FISH), and array-based comparative genomic hybridization, in order to identify biomarkers for lMCL diagnosis and prognosis. Seven lMCL patients were included. All had bone marrow involvement without lymphadenopathy. An lMCL phenotype was distinct from that of cMCL and aMCL: SOX11-, ATM+, PARP1+/-, and low KI67 (average 2 %). Beyond the t(11;14) translocation, fewer secondary cytogenetic alterations were found in lMCL compared to cMCL and aMCL, including deletion of PARP1 and 13q14. At last follow-up, one patient with lMCL had died of disease and another had progressive disease. These patients were respectively 13q14 deletion- and PARP1-positive. One other case of lMCL harbored a 13q14 deletion associated with PARP1 deletion. This patient had indolent disease. lMCL has a particular phenotype and fewer secondary cytogenetic alterations than cMCL and aMCL. PARP1 protein expression and 13q14 deletion are associated with a progressive clinical course of lMCL and should be included in initial diagnostic studies as predictors of unfavorable outcome. PARP1 deletion is involved in lMCL pathogenesis and might confer advantage.

Bilateral ocular panadnexal mass as initial presentation of systemic blastoid variant of mantle-cell lymphoma

A 66-year-old man developed a slowly enlarging, bilateral, painless, periorbital, and orbital swelling with ptosis, nonaxial proptosis, chemosis, exposure keratopathy, and decreased vision in both eyes. He had fever, night sweats, and weight loss (B-symptoms), along with lymphadenopathy and elevated serum lactate dehydrogenase, with no prior history of lymphoma. A transpalpebral incisional biopsy revealed a rare case of mantle-cell lymphoma of blastoid variant, stage IVB. The main immunophenotype characteristics were cyclin D1+, CD5+, CD10-, CD23-, Bcl-6-/+, and a high (up to 80%) Ki-67 proliferation index. Following an excellent response to the immune-chemotherapy treatment plan, all ocular adnexal lymphoma manifestations disappeared completely; however, 13 months after the initial presentation, there was a recurrence of the disease with rapid worsening and death. The blastoid variant of mantle cell lymphoma, a rare subtype of mantle-cell lymphoma, is a highly aggressive neoplasm, ultimately having a fatal outcome. As the initial manifestation of the disease, ocular adnexal region blastoid variant of mantle-cell lymphoma is an exceptional event, with only one previous case reported.

Bortezomib for the treatment of mantle cell lymphoma: an update

Bortezomib is a first in class proteasome inhibitor, initially approved by the US Food and Drug Administration for the treatment of plasma cell myeloma. Bortezomib has been approved for the treatment of relapsed and refractory mantle cell lymphoma (MCL) and, more recently, in the upfront setting as well. Treatment algorithms for MCL have rapidly evolved over the past two decades, and the optimal regimen remains to be defined. The choice of treatment regimen is based on disease risk stratification models, the expected toxicity of antineoplastic agents, the perceived patient ability to tolerate the planned treatments and the availability of novel agents. As new drugs with novel mechanisms of action and variable toxicity profiles come into use, treatment decisions for a given patient have become increasingly complex. This article provides an overview of the evolving use of bortezomib in the rapidly changing management landscape of MCL.

Pretransplantation Minimal Residual Disease Predicts Survival in Patients with Mantle Cell Lymphoma Undergoing Autologous Stem Cell Transplantation in Complete Remission

Autologous stem cell transplantation (ASCT) is standard therapy for mantle cell lymphoma (MCL) in remission after induction chemotherapy, with the best results for patients in complete remission (CR). We hypothesized that evaluation of minimal residual disease (MRD) before ASCT could further stratify outcomes for these patients. Patients with MCL who underwent ASCT in clinical CR between 1996 and 2011 with pretransplantation MRD testing were eligible. Presence of a clonal IgH rearrangement, t(11; 14) by PCR or positive flow cytometry from blood or bone marrow, was considered positive. An adjusted proportional hazards model for associations with progression-free (PFS) and overall survival (OS) was performed. Of 75 MCL patients in CR, 8 (11%) were MRD positive. MRD positivity was associated with shorter OS and PFS. The median OS for MRD-negative patients was not reached, with 82% survival at 5 years, whereas for the MRD-positive patients, median OS was 3.01 years (hazard ratio [HR], 4.04; P = .009), with a median follow-up of 5.1 years. The median PFS for MRD-negative patients was not reached with 75% PFS at 5 years, whereas for MRD-positive patients, it was 2.38 years (HR, 3.69; P = .002). MRD positivity is independently associated with poor outcomes after ASCT for MCL patients in CR.

The role of fluorine-18 fluorodeoxyglucose PET in prognosis evaluation for stem cell transplantation of lymphoma: a systematic review and meta-analysis

The role of fluorine-18 fluorodeoxyglucose PET (F-FDG PET) in prognostic evaluation of pre-stem cell transplantation (SCT) and post-SCT is still uncertain. A systematic review and meta-analysis were carried out to detect the prognostic power of F-FDG PET. 'PubMed', EMBASE, and Springer were searched for relevant articles. Subgroup analysis was carried out to evaluate the F-FDG PET in predicting the prognosis between Hodgkin lymphoma (HL) and non-Hodgkin lymphoma. Finally, 17 studies that included 1192 patients were eligible, 16 studies for progression-free survival (PFS) and 12 studies for overall survival (OS). For the pre-SCT PET or PET/computed tomography scan, the combined hazard ratios (HRs) of PET for PFS and OS were 2.32 and 2.64, respectively. Subgroup analysis showed that the HRs of PFS for HL and non-Hodgkin lymphoma were 3.28 and 2.00, respectively. For the post-SCT PET scan, the combined HR for PFS was 4.61. The sensitivity analysis showed that exlcusion of any single study had no significant effect on HR. We found that F-FDG PET was especially effective in predicting pre-STC and post-STC prognosis. The patients with a negative PET scan had a better prognosis compared with those with a positive scan in PFS and OS. In the subgroup analysis, F-FDG PET had a higher value in predicting prognosis before SCT for HL patients.

Comparison between whole-body MRI with diffusion-weighted imaging and PET/CT in staging newly diagnosed FDG-avid lymphomas

OBJECTIVES

To compare whole body-MRI (WB-MRI) with diffusion-weighted imaging and FDG-PET/CT in staging newly diagnosed FDG-avid lymphomas.

METHODS

68 patients (37 males, 31 females; median age 42 years; range 15-86 years) with histologically confirmed lymphoma (37 Classical Hodgkin, 16 Diffuse large B-cell, 10 Follicular, 5 Mantle cell) underwent both MRI and FDG-PET/CT before treatment. Ann Arbor stages obtained with WB-MRI and FDG-PET/CT were compared using Cohen's k statistics. Moreover WB-MRI and FDG-PET/CT stages were compared with the pathological stages obtained after the diagnostic iter using also bone marrow and available biopsies if clinically indicated.

RESULTS

The agreement between WB-MRI and FDG-PET/CT was excellent. WB-MRI stage was equal to those of FDG-PET/CT in 62/68 patients (91.2%). There was an excellent agreement between WB-MRI stage and pathological stage (63/68 patients; 92.6%), and between FDG-PET/CT and pathological stage (64/68 patients; 94.1%). The differences between the stages were more frequent in the patients with Mantle cell lymphoma.

CONCLUSIONS

WB-MRI can be considered as a promising technique for FDG-avid lymphoma staging.

Rituximab plus hyper-CVAD alternating with MTX/Ara-C in patients with newly diagnosed mantle cell lymphoma: 15-year follow-up of a phase II study from the MD Anderson Cancer Center

Intensive chemotherapy regimens containing cytarabine have substantially improved remission durability and overall survival in younger adults with mantle cell lymphoma (MCL). However, there have been no long-term follow-up results for patients treated with these regimens. We present long-term survival outcomes from a pivotal phase II trial of rituximab, hyper-fractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone alternating with methotrexate and cytarabine (R-HCVAD/MA). At 15 years of follow-up (median: 13·4 years), the median failure-free survival (FFS) and overall survival (OS) for all patients was 4·8 years and 10·7 years, respectively. The FFS seems to have plateaued after 10 years, with an estimated 15-year FFS of 30% in younger patients (≤65 years). Patients who achieved complete response (CR) after 2 cycles had a favourable median FFS of 8·8 years. Six patients developed myelodysplastic syndrome/acute myeloid leukaemia (MDS/AML) whilst in first CR. The 10-year cumulative incidence of MDS/AML of patients in first remission was 6·2% (95% confidence interval: 2·5-12·2%). In patients with newly diagnosed MCL, R-HCVAD/MA showed sustained efficacy, with a median OS exceeding 10 years in all patients and freedom from disease recurrence of nearly 15 years in almost one-third of the younger patients (≤65 years).

Bortezomib and fenretinide induce synergistic cytotoxicity in mantle cell lymphoma through apoptosis, cell-cycle dysregulation, and IκBα kinase downregulation

Mantle cell lymphoma (MCL) remains incurable for most patients, and proteasome inhibitors like bortezomib induce responses in a minority of patients with relapsed disease. Fenretinide is a retinoid that has shown preclinical activity in B-cell lymphomas. We hypothesized that these agents could yield augmented antitumor activity. MCL lines (Granta-519, Jeko-1, and Rec-1) were treated with escalating concentrations of bortezomib and fenretinide singly and in combination. Cytotoxicity was assessed using the MTT assay. Flow cytometric methods were used to assess apoptosis and necrosis, with annexin V-FITC/propidium iodide staining, and G1 and G2 cell-cycle changes were assessed by DAPI staining. Changes in cyclin D1, cyclin B, IκBα, and IKKα expressions were quantified by western blotting. Cytotoxicity was mediated through apoptosis; both agents showed observed versus expected cytotoxicities of 92.2 versus 55.1% in Granta-519, of 87.6 versus 36.3% in Jeko-1, and of 63.2 versus 29.8% in Rec-1. Isobolographic analysis confirmed synergy in Jeko-1 and Rec-1 cell lines. Bortezomib induced G2-phase arrest, with a 1.7-fold increase compared with control, and fenretinide resulted in G1-phase arrest, with an increase of 1.3-fold compared with control. In the combination, G2-phase arrest predominated, with a 1.4-fold increase compared with control, and there was reduced expression of cyclin D1 to 24%, cyclin B to 52 and 64%, cyclin D3 to 25 and 43%, IκBα to 23 and 46%, and IκBα kinase to 34 and 44%. Bortezomib and fenretinide exhibit synergistic cytotoxicity against MCL cell lines. This activity is mediated by IκBα kinase modulation, decreased cyclin expression, cell cycle dysregulation, and apoptotic cell death.

Combined systemic and ocular chemotherapy for anterior segment metastasis of systemic mantle cell lymphoma

Background

Mantle cell lymphoma (MCL) is an aggressive subtype of non-Hodgkin’s lymphoma that rarely metastasizes to the iris and the anterior segment. Blastic/pleomorphic morphology is thought to have an adverse effect on prognosis in MCL. MCL is resistant to conventional chemotherapeutic regimens with a tendency for multiple relapses. Management of anterior segment metastasis of systemic MCL has not been described in literature.

Findings

A 58-year-old male presented with an aggressive, relapsing, metastatic, systemic blastic variant of MCL with ocular involvement. At the time of initial presentation, large tumor cells were visible in the anterior chamber (AC) along with hypopyon and fibrin. The AC cells stained positively for CD20. The iris was thickened and coated with lymphoma cells. Iris neovascularization was present. Given extensive systemic and ocular involvement, the patient was given combination chemotherapy with systemic ibrutinib and intravitreal injections of methotrexate and rituximab. The disease response was monitored using multimodal imaging, including anterior segment optical coherence tomography and ultrasound biomicroscopy. Following combination of systemic and intraocular chemotherapy, there was a marked decrease in the ocular tumor load and the systemic disease.

Conclusions

Combination therapy with intravitreal injections of chemotherapeutic agents targeting monoclonal B-cell population and novel systemic agents may help to achieve remission in anterior segment metastasis of aggressive subtypes of NHL such as blastic variant of MCL. Multimodal imaging may assist in the management of these cases.

Ki-67 Labeling Indices in 'Classic' versus 'Blastoid' Mantle Cell Lymphomas--Proposed Cutoff Values for Routine Diagnostic Workup

BACKGROUND

Mantle-cell lymphoma (MCL) is a unique entity of peripheral B-cell lymphoma that has a discrete morphologic, immunologic, and genetic phenotype, with more common 'classic' and less frequent 'blastoid' and 'pleomorphic' variants, associated with an aggressive clinical course. The aim of this study was to analyze proliferation (Ki-67) indices of 'classic' (c-MCL) and 'blastoid' (b-MCL) variants of a cohort of MCL and to suggest cut off values for the Ki-67 proliferation index in these two subsets.

MATERIALS AND METHODS

MCL cases diagnosed over 4 1/2 years at Section of Histopathology, Department of Pathology and Laboratory Medicine, Aga Khan University Hospital, Karachi were retrieved and reviewed. Ki-67 labelling was scored and analysed.

RESULTS

A total of 90 of cases of MCL were scrutinized. Mean age±SD was 60.2±12.5 years and the male to female ratio was 4:1, with 67 (75%) cases of c-MCL and 23 (25%) cases of b-MCL. Most samples were lymph node biopsies (n=68), whereas the remainder were from various extranodal sites The mean Ki-67 proliferation index was 29.5%±14.4% in classic variants and 64.4±15.2% for the blastoid variant, the difference being statistically significant (p=0.029).

CONCLUSIONS

It was concluded that differential cut-off values of Ki-67 labeling may be used in more objective way to reliably classify MCL into classic or blastoid variants by diagnostic pathologists. We propose a <40 proliferative index to be suggestive of c-MCL and one of >50 for the blastoid variant.

No difference in CCND1 gene expression between breast cancer patients with and without lymph node metastasis in a Southern Brazilian sample

The Cyclin D1 protein has been extensively studied over the last decades, for its various roles in physiological processes, both in normal and cancer cells. Gene amplifications and overexpression of CCND1 are frequently reported in several types of cancers, including breast carcinomas, showing the increasing relevance of Cyclin D1 in tumorigenesis. Little is known about the role of this protein in the metastatic process, and the main objective of this study was to evaluate the importance of the CCND1 as a potential marker of tumor progression in breast carcinomas, in a sample collected in Southern Brazil. We studied 41 samples of formalin-fixed paraffin-embedded tissue sections from invasive ductal breast carcinomas subdivided into metastatic (n = 19) and non-metastatic (n = 22) tumors. Gene expression analysis was performed through Quantitative Real-Time PCR and immunohistochemistry. In spite of the higher expression levels of CCND1 mRNA and protein in tumors when compared with the control samples, no differences were observed between the metastatic and non-metastatic groups, suggesting that, in these samples, the expression of CCND1 has no significant influence on the metastatic process. Further studies must be performed in an attempt to clarify the diagnostic and prognostic value of Cyclin D1 in breast cancers, as well as the mechanisms that trigger its overexpression in tumors.

Eosinophilic pustular folliculitis associated with hematological disorders: A report of two cases and review of Japanese literature

Eosinophilic pustular folliculitis (EPF) occurs in patients with hematological disorders. However, clinical information about hematological disorder-associated EPF is scarce. We report two cases of EPF associated with mantle cell lymphoma and reviewed the available published work on Japanese cases. We identified a total of 23 Japanese cases, including the two cases reported here, who had hematological disorder-associated EPF. Fourteen cases were associated with treatment for hematological malignancies (transplantation-related EPF) and nine cases were associated with hematological malignancies themselves (hematological malignancy-related EPF). Although the skin eruption was clinically indistinguishable between the two subtypes, transplantation-related EPF occurred on the face and trunk of young and middle-aged men and women, whereas hematological malignancy-related EPF occurred mostly on the face of older men. Peripheral blood eosinophilia was more frequently observed in transplantation-related EPF. These observations suggest variations among patients with EPF associated with hematological disorders.

Treatment options for mantle cell lymphoma

INTRODUCTION

In this article, we provide an accurate overview of both standard treatment option and novel promising therapeutics. Major impact is on novel agents now being tested in randomized clinical trials. While the initial data are promising, they may rapidly expand treatment options, change existing paradigms and further improve outcomes for mantle cell lymphoma (MCL) patients.

AREAS COVERED

MCL is a disease with indolent histology, but aggressive clinical course. However, for now, MCL remains incurable and the search for the most effective and tumor-specific treatment still represents a great challenge for oncohematologists. However, the implementation of chemotherapy together with the anti-CD20 antibody rituximab, as well as the growing use of autologous stem cell transplantation in first remission, have improved effects of treatment in MCL, including even some improvement in overall survival. Recently, treatment modalities for MCL have been expanded by strategies based on several biologically targeted agents, including m-TOR kinase or proteasome inhibitors and immunomodulatory agents, such as lenalidomide. B-cell receptor pathway inhibitors, such as ibrutinib and idelalisib, and histone deacetylase or cyclin-dependent kinase inhibitors have also shown promising activity in resistant or relapsed disease.

EXPERT OPINION

Although enormous progress was made in the treatment of MCL over the last year, the disease remains incurable. One chance for the significant life prolongation is intensive treatment with consolidative auto SCT. However, real progress may be afforded by developing the novel agents described in this article. In this way, MCL may soon become another potentially curable oncological malignancy.

De Novo CD5 Negative Blastic Mantle Cell Lymphoma Presented with Massive Bone Marrow Necrosis without Adenopathy or Organomegaly

The recent World Health Organization (WHO) classification defines mantle cell lymphoma (MCL) as a distinct entity characterized by a unique immunophenotype and a molecular hallmark of chromosomal translocation t(11;14)(q13;q32). We report an unusual case of an advanced stage of CD5 negative MCL with a blastoid variant with a massive bone marrow (BM) necrosis as an initial presenting feature, with no adenopathy or hepatosplenomegaly. The pathologic features showed blastoid variant of MCL and flow cytometry showed that the tumor cells were CD5−, CD19+, CD20+, FMC-7+, CD23−, and lambda light chain restricted. Chromosomal analysis, using karyotype and fluorescent in situ hybridization (FISH), demonstrated karyotypic abnormalities in addition to the t(11;14). Our case study may be reported as a unique case of CD5− blastic MCL with unusual presentation and findings which made the diagnosis of MCL difficult.

Do mantle cell lymphomas have an 'Achilles heel'?

PURPOSE OF REVIEW

Mantle cell lymphoma (MCL) is a mature B-cell malignancy that continues to have a high mortality rate. In this article, we discuss key pathogenic pathways in MCL biology and their possible therapeutic targeting.

RECENT FINDINGS

In addition to cyclin-D1, the transcription factor SOX-11 emerged as a common characteristic of MCL. Genomic studies have identified a number of recurrently mutated genes; in order of descending frequency these include ATM, CCND1, UBR5, TP53, BIRC3, NOTCH1/2 and TRAF2. However, no clear oncogenic driver has been identified. In contrast, several observations indicate that MCL cells are antigen-experienced cells and that the tumor microenvironment and B-cell receptor engagement are important. This is underscored by the impressive clinical responses achieved with the Bruton's tyrosine kinase inhibitor ibrutinib. Recently identified activating mutations in the noncanonical nuclear factor-kappa B pathway could give rise to ibrutinib resistance. Poly-ADP ribose polymerase and aurora kinase inhibitors may be synthetic lethal with the common aberrations in DNA damage pathways found in MCL. Also, ABT-199, a potent and selective inhibitor of B-cell lymphoma 2, has promising activity in early studies.

SUMMARY

MCL is a heterogeneous disease, and no single Achilles heel has been identified. Nevertheless, genomic, molecular and clinical studies have revealed vulnerabilities that can be exploited for effective therapy.

MDCT of extranodal mantle cell lymphoma: a single institute experience

OBJECTIVE

To study the pattern of extranodal and particularly gastrointestinal (GI) involvement of mantle cell lymphoma (MCL) on MDCT MATERIALS AND METHODS: In this IRB-approved, HIPAA compliant retrospective study, MDCT features of 78 patients (62 males and 16 females, mean age 57 years) with MCL including 28 patients at presentation were reviewed. Clinical and histopathological (blastoid vs. non-blastoid) data were noted from medical records.

RESULTS

Extranodal involvement was present in overall 51/78 patients on CT (65%), 18/28 (64%) patients at presentation. Spleen (21/78-27%) and bowel (19/78-24%) were the most common sites of extranodal involvement by MCL on imaging, followed by lungs (10/78-13%) and skin/subcutaneous tissue (9/78-12%). Bowel involvement was either in the form of endophytic polypoidal lesions (n = 11, mean size 3.1 cm), as focal mild bowel wall thickening (n = 5, mean thickness 1.4 cm), or as combination of the two (n = 3). Blastoid histology was present in 14/78 (24%) patients and was statistically associated with skin/subcutaneous involvement (p < 0.05; Fisher's exact t test). Median follow-up was 72 months during which 21 patients died with median survival of 48 months (26 months for blastoid histology vs. 47 months for non-blastoid histology). There was no statistical correlation between sites of involvement and survival.

CONCLUSIONS

MCL has a predilection for extranodal disease, predominantly involving the spleen, bowel, lungs, and subcutaneous tissue. GI involvement on CT is in the form of endoluminal polypoidal lesions and mild bowel wall thickening. Skin/subcutaneous involvement was statistically more common with blastoid histology in our study.

MYC overexpression correlates with MYC amplification or translocation, and is associated with poor prognosis in mantle cell lymphoma

AIMS

We aimed to investigate MYC expression and chromosomal aberration in mantle cell lymphoma (MCL), and the clinical significance of these factors.

METHODS AND RESULTS

Sixty-five patients with MCL, including 54 classic, nine blastoid and two pleomorphic variants, were enrolled. Expression of MYC, Ki67 and p53 was assessed by immunohistochemistry. MYC amplification or translocation was examined by fluorescence in-situ hybridization. MYC expression was higher in blastoid/pleomorphic MCL variants (mean, 19.0%) than in classic MCL (mean, 1.9%; P < 0.001). Expression of p53 and Ki67 was also significantly higher in these variants. MYC amplification was found in two of 53 cases tested, both of which were blastoid variants with high MYC expression (29.7% and 20.4%). MYC translocation was found in two of 52 cases tested, both of which were pleomorphic variants with remarkably high MYC expression (68.5% and 71.0%). High MYC or p53 expression was significantly associated with shortened overall survival and progression-free survival in univariable and multivariable analyses (all P < 0.05).

CONCLUSIONS

MYC overexpression is a negative predictor of MCL patient outcomes. MYC gene amplification or translocation might be related to the pathogenesis of MCL, particularly in blastoid/pleomorphic variants.

Targeting Wnt pathway in mantle cell lymphoma-initiating cells

BACKGROUND

Mantle cell lymphoma (MCL) is an aggressive and incurable form of non-Hodgkin's lymphoma. Despite initial intense chemotherapy, up to 50% of cases of MCL relapse often in a chemoresistant form. We hypothesized that the recently identified MCL-initiating cells (MCL-ICs) are the main reason for relapse and chemoresistance of MCL. Cancer stem cell-related pathways such as Wnt could be responsible for their maintenance and survival.

METHODS

We isolated MCL-ICs from primary MCL cells on the basis of a defined marker expression pattern (CD34-CD3-CD45+CD19-) and investigated Wnt pathway expression. We also tested the potential of Wnt pathway inhibitors in elimination of MCL-ICs.

RESULTS

We showed that MCL-ICs are resistant to genotoxic agents vincristine, doxorubicin, and the newly approved Burton tyrosine kinase (BTK) inhibitor ibrutinib. We confirmed the differential up-regulation of Wnt pathway in MCL-ICs. Indeed, MCL-ICs were particularly sensitive to Wnt pathway inhibitors. Targeting β-catenin-TCF4 interaction with CCT036477, iCRT14, or PKF118-310 preferentially eliminated the MCL-ICs.

CONCLUSIONS

Our results suggest that Wnt signaling is critical for the maintenance and survival of MCL-ICs, and effective MCL therapy should aim to eliminate MCL-ICs through Wnt signaling inhibitors.

Mantle cell lymphoma first presenting as immune complex-mediated glomerulonephritis: a case report

INTRODUCTION

Kidney involvement in non-Hodgkin lymphoma is recognized but mostly diagnosed following a diagnosis of lymphoma. We describe a rare case of mantle cell lymphoma, a B-cell-type non-Hodgkin lymphoma, first presenting with immune complex glomerulonephritis.

CASE PRESENTATION

We report the case of a 58-year-old Sri Lankan man who presented with gross hematuria. Further investigation revealed bicytopenia with splenomegaly and elevated serum creatinine. He had a renal biopsy, which revealed acute immune complex glomerulonephritis with interstitial inflammation. Results from an initial bone marrow biopsy and blood imaging were inconclusive. Three months later his renal function had deteriorated and a lymph node biopsy revealed mantle cell lymphoma. Within three months of initiating chemotherapy, his renal function returned to normal levels and remained normal at one year of follow-up.

CONCLUSIONS

It is important to have a high degree of suspicion when patients present with acute immune complex glomerulonephritis with no other identifiable cause, because it could be the first presentation of a non-Hodgkin lymphoma such as mantle cell lymphoma.

Prognostic model for mantle cell lymphoma in the rituximab era: a nationwide study in Japan

Mantle cell lymphoma (MCL) is essentially incurable with conventional chemotherapy. The MCL International Prognostic Index (MIPI) is a validated specific prognostic index, but was derived from patients with advanced-stage disease primarily in the pre-rituximab era. We analysed 501 MCL patients (median age, 67 years; range 22-90) treated with rituximab-containing chemotherapy, and evaluated the prognostic factors adjusted by the treatment. Five-year overall survival (OS) in the low, intermediate and high MIPI groups was 74%, 70% and 35%, respectively. Additional to MIPI risk factors, multivariate analysis revealed that low serum albumin and bone-marrow involvement were also significantly associated with a poor outcome. The revised-MIPI (R-MIPI) was constructed using six factors, namely age, performance status, white blood cell count, serum lactate dehydrogenase, bone-marrow involvement and serum albumin, which is divided into four prognostic groups. Five-year OS in low, low-intermediate (L-I), high-intermediate (H-I) and high R-MIPI groups was 92%, 75%, 61% and 19%, respectively. Hazard ratio for OS of L-I, H-I and high risk to low risk patients were 5·4, 8·3 and 33·0, respectively. R-MIPI, a new prognostic index with easy application to the general patient population, shows promise for identifying low- and high-risk MCL patients in the rituximab era.