CD5- mantle cell lymphoma

Skin Involvement by Hematological Neoplasms with Blastic Morphology: Lymphoblastic Lymphoma, Blastoid Variant of Mantle Cell Lymphoma and Differential Diagnoses

Hematological neoplasms sharing a blastic morphology may involve the skin. The skin may be either the primary site of occurrence of hematological malignancies with blastic features or cutaneous lesions are the first manifestation of an underlying systemic malignancy. The assessment of skin biopsies of hematological neoplasms with blastic features poses diagnostic problems and requires expert hematopathologists considering a wide range of differential diagnoses. The precise diagnosis of diseases sharing blastic features but with different outcomes and requiring distinct therapies is essential for patient management. The present paper mainly focuses on cutaneous involvement of the blastoid variant of mantle cell lymphoma and lymphoblastic lymphoma of B-cell or T-cell origin. The relevant literature has been reviewed and the clinical aspects, pathological features, prognosis, and therapy of both blastoid mantle cell lymphoma and lymphoblastic lymphoma involving the skin are discussed. A focus on other hematological entities with blastic features, which may involve the skin, to be taken into consideration in differential diagnosis is also given.

Mantle cell lymphoma in 2022-A comprehensive update on molecular pathogenesis, risk stratification, clinical approach, and current and novel treatments

The field of mantle cell lymphoma (MCL) has witnessed remarkable progress due to relentless advances in molecular pathogenesis, prognostication, and newer treatments. MCL consists of a spectrum of clinical subtypes. Rarely, atypical cyclin D1-negative MCL and in situ MCL neoplasia are identified. Prognostication of MCL is further refined by identifying somatic mutations (such as TP53, NSD2, KMT2D), methylation status, chromatin organization pattern, SOX-11 expression, minimal residual disease (MRD), and genomic clusters. Lymphoid tissue microenvironment studies demonstrated the role of B-cell receptor signaling, nuclear factor kappa B (NF-kB), colony-stimulating factor (CSF)-1, the CD70-SOX-11 axis. Molecular mechanism of resistance, mutation dynamics, and pathogenic pathways (B-cell receptor (BCR), oxidative phosphorylation, and MYC) were identified in mediating resistance to various treatments (bruton tyrosine kinase (BTK) inhibitors [ibrutinib, acalabrutinib]. Treatment options range from conventional chemoimmunotherapy and stem cell transplantation (SCT) to targeted therapies against BTK (covalent and noncovalent), Bcl2, ROR1, cellular therapy such as anti-CD19 chimeric antigen receptor therapy (CAR-T), and most recently bispecific antibodies against CD19 and CD20. MCL patients frequently relapse. Complex pathogenesis and the management of patients with progression after treatment with BTK/Bcl2 inhibitors and CAR-T (triple-resistant MCL) remain a challenge. Next-generation clinical trials incorporating newer agents and concurrent translational and molecular investigations are ongoing.

CD5-negative mantle cell lymphoma: clinicopathologic features of an indolent variant that confers a survival advantage

Conventionally, mantle cell lymphoma (MCL) is an aggressive CD5-positive B-cell malignancy with poor prognosis and limited survival. However, a small subset of patients presents with indolent disease and can be managed on a 'watch and wait' approach. CD5-negative MCL has recently been recognized as a more favorable variant of MCL, but its clinical and biological implications remain ill-defined. We performed the most extensive review to-date of all reported cases of CD5-negative MCL and included unpublished cases diagnosed at our institutions to further characterize this disease subset. Based on our analysis of 356 cases of CD5-negative MCL, we conclude that median overall survival exceeds 14 years and is independent of favorable prognostic markers such as leukemic non-nodal disease, absence of SOX11, and low Ki-67.

How to Diagnose and Treat CD5-Positive Lymphomas Involving the Spleen

Patients with CD5-expressing lymphomas presenting with splenomegaly are frequently diagnosed with chronic lymphocytic leukemia. The most important differential diagnosis is mantle cell lymphoma, both in its classical and leukemic, non-nodal forms, given its prognostic and therapeutic implications. Other small B-cell neoplasms that frequently involve the spleen and occasionally express CD5 include the splenic marginal zone lymphoma, hairy cell leukemia and, rarely, lymphoplasmacytic lymphoma. The frequency of CD5 positivity depends in part on the sensitivity of the detection methods employed. Usually, a combination of morphological, immunophenotypic and molecular findings allows for a precise sub-classification of CD5-positive, low-grade B-cell lymphomas of the spleen. Some of these tumors may display a mixture of small and larger B cells, raising the possibility of more aggressive lymphomas, such as diffuse large B-cell lymphomas (DLBCL). Approximately 5-10% of DLBCL are CD5-positive and some may manifest as primary splenic lesions. When available, the morphology of DLBCL in the splenic tissue is distinctive and a leukemic picture is very rare. In conclusion, the appropriate morphological and clinical context assisted by flow cytometry panels and/or immunohistochemistry allows the differential diagnosis of CD5-positive, non-Hodgkin, B-cell lymphomas involving the spleen.

Blastoid Mantle Cell Lymphoma of the Palate: Report of a Rare Aggressive Entity and Review of the Literature

Mantle cell lymphoma (MCL) is a well-defined, non-Hodgkin lymphoma of B-cell origin displaying diverse morphological phenotypes and variable disease course. The World Health Organization recognizes two aggressive histopathologic variants of this type of lymphoma: pleomorphic and blastoid MCL. To date, only few cases of MCL affecting the oral cavity have been reported. Additionally, the involvement of the oral and maxillofacial area by aggressive MCL subsets is considered extremely rare with only two patients reported in the English language literature to the best of our knowledge. Herein, we describe a 69 year-old male with a prior history of MCL of the right lateral pharyngeal wall developing a recurrent lesion extending to the palatal mucosa as diffuse ulceration and exhibiting histomorphological features of blastoid MCL. We also review the pertinent literature with emphasis on the diagnostic challenges and distinction between the different MCL variants.

Blastoid mantle cell lymphoma presenting as acute leukemia: a case report

Blastoid variant of mantle cell lymphoma (MCL) is an aggressive and incurable form of B-cell lymphoma. Various chemo-immunotherapy regimens have been used with a limited success. Autologous stem cell transplant (ASCT) is being increasingly recommended in first remission for patients with blastoid variant MCL. Here, we describe the case of a 45-year-old lady suffering from blastoid variant of MCL. Patient was administered R-CHOP and underwent autologous stem cell transplant (ASCT). Currently, patient is disease-free and is on a regular follow up for 26 months now. This is an extremely rare case documented in the Indian literature with a long survival post-transplant.

Genomic profiles and clinical outcomes of de novo blastoid/pleomorphic MCL are distinct from those of transformed MCL

Blastoid and pleomorphic mantle cell lymphomas (MCLs) are variants of aggressive histology MCL (AH-MCL). AH-MCL can arise de novo (AH-DN) or transform from prior classic variant MCL (AH-t). This study is the first integrated analysis of clinical and genomic characteristics of AH-MCL. Patient characteristics were collected from diagnosis (AH-DN) and at transformation (AH-t). Survival after initial diagnosis (AH-DN) and after transformation (AH-t) was calculated. Regression tree analysis was performed to evaluate prognostic variables and in univariate and multivariate analyses for survival. Whole-exome sequencing was performed in evaluable biopsy specimens. We identified 183 patients with AH-MCL (108 were AH-DN, and 75 were AH-t; 152 were blastoid, and 31 were pleomorphic). Median survival was 33 months (48 and 14 months for AH-DN and AH-t, respectively; P = .001). Factors associated with inferior survival were age (≥72 years), AH-t category, Ki-67 ≥50% and poor performance status. AH-t had a significantly higher degree of aneuploidy compared with AH-DN. Transformed MCL patients exhibited KMT2B mutations. AH-MCL patients with Ki-67 ≥50% had exclusive mutations in CCND1, NOTCH1, TP53, SPEN, SMARCA4, RANBP2, KMT2C, NOTCH2, NOTCH3, and NSD2 compared with low Ki-67 (<50%). AH-t patients have poor outcomes and distinct genomic profile. This is the first study to report that AH-MCL patients with high Ki-67 (≥50%) exhibit a distinct mutation profile and very poor survival.

A rare case of hairy cell leukemia with co-expression of CD5 and cyclin D1: A diagnostic pitfall

Hairy cell leukemia (HCL) is an uncommon chronic B-cell lymphoproliferative disease with an indolent course. It mainly occurs in elderly men, although abdominal lymphadenopathy is rare. HCL cells are mostly found in the bone marrow, peripheral blood, and spleen and typically express CD11c, CD20, CD25 and CD103. We present a case of HCL with a novel immunophenotype. A 48-year-old woman presented with pancytopenia and splenomegaly. The diagnosis was HCL with lymph node infiltration. Unlike previously described HCL cases, the current case showed strong expression of CD5 and cyclin D1 in the lymph nodes. The patient underwent cladribine chemotherapy, and the leukocyte count increased during and after treatment. The 8-month follow-up revealed that she had recovered well. This case highlights the distinctive immunophenotype of HCL infiltrating the lymph nodes and the potential misdiagnosis of HCL as mantle cell lymphoma. It also adds to our limited understanding of HCL.

A rare case of dual expression of CD5 and CD10 in primary central nervous system diffuse large B-cell lymphoma with prominent starry sky appearance

This case highlights the need for both tissue biopsy for diagnosis in suspected CNS malignancy and comprehensive immune profiling for accurate subclassification.

Blastoid Mantle Cell Lymphoma

Blastoid and pleomorphic mantle cell lymphoma (MCL) are among the worst prognostic, aggressive histology, high-risk variants of MCL, and, in this article, they are presented as blastoid MCL. Blastoid MCL have not been systematically studied, probably due to their rarity. De novo blastoid MCLs have superior outcomes compared with transformed MCL. Compared with classic MCL, extranodal involvement (mainly skin, central nervous system), frequent relapses, and inferior responses to conventional chemoimmunotherapy, BTK inhibitors and venetoclax are frequent in blastoid MCL. KTE-X19 induces excellent response in blastoid MCL. Combinations with novel agents are actively investigated. This article presents a comprehensive review on blastoid MCL in 2020.

Educational Case: Mantle Cell Lymphoma

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.¹.

CD5-negative Mantle Cell Lymphoma: Clinicopathologic Correlations and Outcome in 58 Patients

Mantle cell lymphoma (MCL) represents 4% to 9% of all non-Hodgkin lymphomas and is characterized by CD5 and cyclin D1 expression and t(11;14)(q13;q32). However, about 5% of MCL lack CD5 expression and is poorly characterized. Here, we present 58 patients with CD5 negative (CD5) MCL and compared them with a group of 212 typical CD5 positive (CD5) MCL cases. There were 39 men and 19 women with a median age of 66 years (range, 36 to 88). Compared with CD5 positive (CD5) MCL patients, patients with CD5 MCL showed a lower male-to-female ratio (P=0.006) and a higher frequency of "bone marrow non-nodal" presentation (P=0.01). All other clinicopathologic features, including the frequency of SOX11 expression, were similar between the 2 groups. Treated with similar regimens, patients with CD5 MCL showed a significantly longer progression-free survival (PFS) (P=0.01) and a tendency for longer overall survival (OS; P=0.078) than CD5 positive (CD5) MCL patients. Univariate analysis showed of the well-known poor prognostic factors, only Mantle Cell Lymphoma International Prognostic Index was an inferior prognostic factor and blastoid/pleomorphic morphology and high Ki67 were not associated with prognosis in CD5 MCL patients. Multivariate Cox regression analysis showed CD5 expression was an independent prognostic factor for PFS (P=0.031) but not OS in MCL patients. In conclusion, the results suggest that patients with CD5 MCL have a more favorable prognosis than CD5 MCL patients, although the clinicopathologic features of both groups are largely similar. CD5 MCL may represent a distinct variant of MCL and needs to be included in the differential diagnosis of CD5 small B-cell lymphomas.

Mantle cell lymphoma: 2019 update on the diagnosis, pathogenesis, prognostication, and management

Unprecedented advances in our understanding of the pathobiology, prognostication, and therapeutic options in mantle cell lymphoma (MCL) have taken place in the last few years. Heterogeneity in the clinical course of MCL-indolent vs aggressive-is further delineated by a correlation with the mutational status of the variable region of immunoglobulin heavy chain, methylation status, and SOX-11 expression. Cyclin-D1 negative MCL, in situ MCL neoplasia, and impact of the karyotype on prognosis are distinguished. Apart from Ki-67% and morphology pattern (classic vs blastoid/pleomorphic), the proliferation gene signature has helped to further refine prognostication. Studies focusing on mutational dynamics and clonal evolution on Bruton's tyrosine kinase (BTK) inhibitors (ibrutinib, acalabrutinib) and/or Bcl2 antagonists (venetoclax) have further clarified the prognostic impact of somatic mutations in TP53, BIRC3, CDKN2A, MAP3K14, NOTCH2, NSD2, and SMARCA4 genes. In therapy, long-term follow-up on chemo-immunotherapy studies has demonstrated durable remissions in some patients; however, long-term toxicities, especially from second cancers, are a serious concern with chemotherapy. The therapeutic options in MCL are constantly evolving, with dramatic responses from nonchemotherapeutic agents (ibrutinib, acalabrutinib, and venetoclax). Chimeric antigen receptor therapy and combinations of nonchemotherapeutic agents are actively being studied and our focus is shifting toward making the treatment of MCL chemotherapy-free. Still, MCL remains incurable. The following aspects of MCL continue to pose a challenge: disease transformation, role of the cytokine-microenvironmental milieu, incorporation of positron emission tomography-computerized tomography imaging, minimal residual disease in the prognosis, circulating tumor DNA testing for clonal evolution, predicting resistance to BTK inhibitors, and optimal management of patients who progress on BTK/Bcl2 inhibitors. Next-generation clinical trials should incorporate nonchemotherapeutic agents and personalize the treatment based upon the genomic profile of individual patient. Recent advances in the field of MCL are reviewed.

Immunophenotypic Characterization of Canine Splenic Follicular-Derived B-Cell Lymphoma

Marginal zone lymphoma (MZL) and mantle cell lymphoma (MCL) belong to a subgroup of indolent B-cell lymphomas most commonly reported in the canine spleen. The goal of this study was to characterize the immunophenotype of splenic MZL and MCL in comparison to their human counterparts. Ten MCLs and 28 MZLs were selected based on morphology. A tissue microarray was generated, and expression of CD3, CD5, CD10, CD45, CD20, CD79a, Pax-5, Bcl-2, Bcl-6, cyclin D1, cyclin D3, MCL-1, MUM-1, and Sox-11 was evaluated. Neoplastic cells in all MCLs and MZLs were positive for CD5, CD20, CD45, CD79a, and BCL2 and negative for CD3, CD10, Bcl-6, cyclin D1, and cyclin D3. Positive labeling for Pax-5 was detected in 8 of 10 MCLs and 26 of 28 MZLs. Positive labeling for MUM-1 was detected in 3 of 10 MCLs, and 27 of 28 MZLs were positive for MUM-1. No MCLs but 8 of 24 MZLs were positive for MCL-1. Canine splenic MZL and MCL have a similar immunophenotype as their human counterparts. However, human splenic MCL overexpresses cyclin D1 due to a translocation. A similar genetic alteration has not been reported in dogs. In addition, in contrast to human MZL, canine splenic MZL generally expresses CD5. Following identification of B vs T cells with CD20 and CD3, a panel composed of BCL-2, Bcl-6, MUM-1, and MCL-1 combined with the histomorphological pattern can be used to accurately diagnose MZL and MCL in dogs. Expression of Bcl-2 and lack of MCL-1 expression in MCL may suggest a therapeutic benefit of BCL-2 inhibitors in canine MCL.

Blastoid and pleomorphic mantle cell lymphoma: still a diagnostic and therapeutic challenge!

Blastoid mantle cell lymphoma is characterized by highly aggressive features and a dismal clinical course. These blastoid and pleomorphic variants are defined by cytomorphological features, but the criteria are somewhat subjective. The diagnosis may be supported by a high cell proliferation based on the Ki-67 labeling index. Recent analyses have shown that the Ki-67 index overrules the prognostic information derived from the cytology subtypes. Nevertheless, genetic analysis suggests that blastoid and pleomorphic variants are distinct from classical mantle cell lymphoma. In clinical cohorts, the frequency of these subsets varies widely but probably represents ∼10% of all cases. Chemotherapy regimens commonly used in mantle cell lymphoma, such as bendamustine, rarely achieve prolonged remissions when given at the dosage developed for classical variants of the disease. Thus, high-dose cytarabine–containing regimens with high-dose consolidation may be generally recommended based on the more aggressive clinical course in these patients. However, even with these intensified regimens, the long-term outcome seems to be impaired. Thus, especially in this patient subset, allogeneic transplantation may be discussed at an early time point in disease management. Accordingly, targeted approaches are warranted in these patients, but clinical data are scarce. Ibrutinib treatment results in high rates of responses, but the median duration of remission is <6 months. Similarly, lenalidomide and temsirolimus result in only short-term remissions. Novel approaches, such as chimeric antigenic receptor T cells, may have the potential to finally improve the dismal long-term outcome of these patients.

Immunophenotypic Variations in Mantle Cell Lymphoma and Their Impact on Clinical Behavior and Outcome

Context.—

Immunophenotypic variations in mantle cell lymphoma (MCL) from the classic CD5+/CD10−/CD23−/FMC-7+ immunophenotype have been reported in the literature, but correlation with clinical behavior and outcome has not been fully studied.

Objective.—

To investigate clinicopathologic and prognostic differences between immunophenotypically aberrant MCL and immunophenotypically typical MCL.

Design.—

We evaluated differences in clinical presentation, laboratory parameters, prognostic indices, response to initial treatment, and progression-free and overall survival between patients with aberrant MCL and patients with immunophenotypically typical MCL.

Results.—

There were 158 patients with newly diagnosed cyclin D1 or t(11;14)(q13;q32)+ MCL identified in the original search, of which, 29 patients (18%) showed immunophenotypic aberrancies, with CD23 coexpression being the most common. When compared with 33 randomly selected patients with immunophenotypically typical MCL, statistically significant differences were seen in white blood cell counts (P = .02), in the presence of absolute lymphocytosis (P = .03), in the MCL International Prognostic Index score (P = .02), and in response to initial treatment (P = .04). The “immunophenotypic status” of the MCL was the only independent factor associated with response to treatment (P = .05), but not with the MCL International Prognostic Index score, absolute lymphocytosis, or white blood cell count. No significant differences were seen for progression-free or overall survival.

Conclusions.—

Immunophenotypic variations in MCL are associated with differences in clinical presentation and response to therapy when compared with immunophenotypically typical MCL. However, with current intensive frontline immunochemotherapy, immunophenotypic aberrations do not appear to affect progression-free or overall survival.

A Unique Case of Blastoid Variant of Mantle Cell Lymphoma with an Aberrant CD5-/CD10+/Bcl-6+/CD56+ Immunophenotype: A Case Report

The neural adhesion molecule CD56 is normally expressed on natural killer cells and subsets of T cells and is commonly found in hematolymphoid neoplasms. Expression of CD56 is very rare in B-cell lymphoma and most reported CD56-positive cases were diffuse large B-cell lymphomas. Cases of CD56-positive mantle cell lymphoma (MCL) have not previously been described in the literature. We present a case of CD56-positive MCL. To the best of our knowledge, this is the first case report of MCL expressing CD56.

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.

Orbital mantle cell lymphoma presenting as myasthenia gravis

A 69-year-old man, previously treated with pyridostigmine for myasthenia gravis (manifesting as ptosis and diplopia) was evaluated for several concomitant bilateral anterior orbital masses. Imaging revealed 3 discrete, solid masses within and around the orbits. An incisional biopsy demonstrated atypical lymphocytes positive for CD20 and Cyclin-D1, consistent with mantle cell lymphoma. The patient received induction chemotherapy with a rituximab-based regimen. He experienced resolution of his diplopia and ptosis after one cycle of chemotherapy and achieved complete remission of the orbital masses and myasthenia symptoms after 6 cycles. Myasthenia gravis is most commonly associated with thymoma, but may also be observed with other malignancies. Recognition that orbital lymphoma may coexist with myasthenia gravis will help in expediting the diagnosis of future cases and in guiding treatment decisions.

Mantle Cell Lymphoma: Contemporary Diagnostic and Treatment Perspectives in the Age of Personalized Medicine

Mantle cell lymphoma is a clinically heterogeneous disease occurring within a heterogeneous patient population, highlighting a need for personalized therapy to ensure optimal outcomes. It is therefore critical to understand the benefits and risks associated with both intensive and deintensified approaches. In the following review we provide a therapeutic roadmap to strategically guide treatment for newly diagnosed and relapsed/refractory patients highlighting pivotal and recently published results involving known and novel therapies.

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.

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.

A case of mantle cell lymphoma presenting as IgG4-related dacryoadenitis and sialoadenitis, so-called Mikulicz's disease

Background

Mantle cell lymphoma (MCL) is a relatively uncommon type of non-Hodgkin lymphoma. It develops in the outer edge of a lymph node called the mantle zone. In contrast, IgG4-related dacryoadenitis and sialoadenitis (IgG4-DS) is characterized by elevated serum IgG4 and persistent bilateral enlargement of lacrimal glands (LGs) and salivary glands (SGs), with infiltration of IgG4-positive plasma cells. Recent studies indicated the importance of differentiation between IgG4-DS and malignant lymphoma.

Case presentation

An 82-year-old man was suspected of IgG4-DS because of a high serum IgG level (2174 mg/dL) and bilateral swelling of LGs and SGs. Lip biopsy and fine needle biopsy of submandibular gland were performed, and subsequently, MCL was diagnosed through the histopathological findings.

Conclusions

MCL most commonly occurs in the Waldeyer ring, but rarely in the stomach, spleen, skin, LG, and SG. We report an unusual case of MCL involving LGs and SGs mimicking IgG4-DS, which suggests that IgG4 testing may be useful in the differentiation of IgG4-DS in the presence of bilateral swelling of LGs or SGs.

Diagnostic Pitfalls in "Low-Grade Lymphoma" of the Orbit and Lacrimal Gland

AIMS

To investigate potential diagnostic pitfalls associated with the identification of low grade lymphoma in the orbit and lacrimal gland region.

METHODS

To systemically review all cases diagnosed as low grade lymphoma of orbit and lacrimal gland within a 2 year period at a specialist ophthalmic centre. To ascertain the frequency of diagnostic errors in this group of cases, in particular to look for known pitfalls associated with follicular colonisation by marginal zone lymphoma and the recently identified atypical variant of follicular lymphoma (FL). A series of 21 cases were reviewed.

RESULTS

We identified two diagnostic errors; one case of extra nodal marginal zone lymphoma (ENMZL) which showed follicular colonisation and was misinterpreted as a FL and a case of missed mantle cell lymphoma (MCL). We identified no cases of atypical FL.

CONCLUSION

Within the orbit and lacrimal gland the term "low grade lymphoma" encompasses the following types of lymphoma: ENMZL, FL, MCL and chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL). The typical and atypical immunophenotype of these entities is discussed. The diagnosis of ENMZL, by far the most common low grade lymphoma to occur in these areas, is to some extent a difficult diagnosis and is often one of exclusion. The pitfalls of follicular colonisation and the concept of atypical follicular lymphoma are discussed.

Clinicopathologic features and management of blastoid variant of mantle cell lymphoma

The blastoid variant of mantle cell lymphoma (MCL), which accounts for less than one-third of MCL, may arise de novo or as a transformation from the classical form of MCL. Blastoid variant, which predominantly involves men in their sixth decade, has frequent extranodal involvement (40-60%), stage IV disease (up to 85%) and central nervous system (CNS) involvement. Diagnosis relies on morphological features and is challenging. Immunophenotyping may display CD23 and CD10 positivity and CD5 negativity in a subset. Genetic analysis demonstrates an increased number of complex genetic alterations. Blastoid variant responds poorly to conventional chemotherapy and has a short duration of response. Although the optimal therapy remains to be established, CNS prophylaxis and the use of aggressive immunochemotherapy followed by autologous stem cell transplant may prolong the remission rate and survival. Further studies are crucial to expand our understanding of this disease entity and improve the clinical outcome.

Detection of minimal residual disease in mantle cell lymphoma-establishment of novel eight-color flow cytometry approach

BACKGROUND

Minimal residual disease (MRD) detection is an essential tool for therapy response assessment in a considerable number of hematooncologic disorders, including mantle cell lymphoma (MCL). Flow cytometry (FCM) ranks among the most effective approaches, which allows rapid sample processing and compete successfully with highly sensitive molecular methods like polymerase chain reaction. Because FCM is ordinarily applied to detect MRD in B-lineage diseases like chronic lymphocytic leukemia, a similar method could be used in MCL. We decided to test our novel eight-color FCM approach in MCL MRD detection.

METHODS

Using an eight-color FCM protocol designed by us, the expression of 24 selected surface antigens in a cohort of 30 patients with newly diagnosed leukemic MCL and 20 normal controls were compared to establish markers that can reliably distinguish normal B-lymphocytes from the MCL population. The sensitivity of the designed protocol was tested using serial dilution studies.

RESULTS

Although MCL presents high immunophenotypic variability, the combination of CD20/23/5/19/200/62L/3/45 seems to be very favorable in flow cytometric MRD measurement.

CONCLUSIONS

Our eight-color FCM protocol could easily detect MRD in MCL patients, and reaches a sensitivity of up to 2 × 10(-4) .

Follicular lymphoma with progression to diffuse large B-cell lymphoma and concurrent CD5-negative mantle cell lymphoma-3 entities in a lymph node

A 68-year-old woman with a history of follicular lymphoma had pathological findings of grade 3B follicular lymphoma, mantle cell lymphoma (MCL), and diffuse large B-cell lymphoma (DLBCL) identified in 1 lymph node. The DLBCL appeared to be a transformation of the follicular lymphoma. The nodules were diffusely and strongly positive for CD20, BCL6, and BCL2. CD43 highlighted smaller lymphocytes in a fraction of the nodules. BCL1 staining was variable with a mixture of nodular and mantle zone patterns. The diffuse areas showed weaker positivity for CD10, BCL2, and BCL6. CD3 and CD5 highlighted intermixed T cells. The Ki-67 proliferative index was overall estimated to be 60%. Fluorescent in situ hybridization performed on the lymph node was positive for CCND1/IGH. The patterns of BCL1 and BCL6 staining demonstrated 2 separate populations of neoplastic B lymphocytes.

Lymphomas of the Gastrointestinal Tract: An Update

The gastrointestinal tract is the most common extranodal site of non-Hodgkin lymphoma. Certain lymphomas have a predilection for the gastrointestinal tract, including extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue, mantle cell lymphoma, natural killer/T-cell lymphoma, and enteropathy-associated T-cell lymphoma. Follicular lymphoma may also be primary to the gastrointestinal tract. In addition to diagnosing neoplastic conditions, it is important to differentiate lymphomas from atypical reactive proliferations. Recent research relevant to non-Hodgkin lymphomas involving this location is reviewed with an emphasis on novel and evolving areas of classification.

Unusual concomitant rearrangements of Cyclin D1 and MYC genes in blastoid variant of mantle cell lymphoma: Case report and review of literature

We report herein a case of blastoid variant mantle cell lymphoma (MCL) with both aberrant phenotype and unusual genetics. Unexpectedly, lymphoma cells were CD5(-) and CD10(+). Standard karyotype and FISH techniques showed that tumor cells carried two distinct translocations which had not been reported together in a same tumor. The first translocation juxtaposed the immunoglobulin lambda light chain locus with CCND1 locus, leading to Cyclin D1 overexpression. The second translocation revealed MYC rearrangement with a non-immunoglobulin gene partner located on the short arm of chromosome 4. The interpretation of the case on tissue sections alone could have been challenging. Indeed, the lack of CD5 and expression of CD10 associated with MYC rearrangement detected on interphasic nuclei could support the diagnosis of diffuse large B-cell lymphoma or Burkitt lymphoma. This distinction is also especially important as these lymphoma subtypes require specific treatment.

Nodal and leukemic small B-cell neoplasms

The small B-cell neoplasms represent some of the most frequently encountered lymphoproliferative disorders in routine surgical pathology practice. This report reviews the current diagnostic criteria for classifying small B-cell neoplasms and distinguishing them from newly recognized precursor conditions that do not appear to represent overt lymphomas. Newly available immunohistochemical stains and molecular studies that may assist in the diagnosis and classification of these neoplasms are also discussed.

Mantle cell lymphoma of the oral cavity with multiple foci: a case report and review of the literature

Non-Hodgkin lymphomas (NHLs) are often present outside the lymph nodes. Although primary extranodal NHLs form a substantial part of all NHLs, reports on oral primary extra nodal NHLs are rare. Mantle cell lymphoma (MCL) is a rare B-cell neoplasm that has only recently been defined as a distinct entity. MCL of the oral cavity is an uncommon diagnosis. Most oral MCLs occur in an elderly male population and have a possible predilection for the palate. The microscopic diagnosis can be challenging, given its similar appearance to other small cell lymphomas, requiring a comprehensive immunohistochemical panel for the accurate diagnosis. Like MCL occurring in other sites in the body, the prognosis and outcome of oral MCL appears to be poor.

Discordant lymphoma consisting of splenic mantle cell lymphoma and marginal zone lymphoma involving the bone marrow and peripheral blood: a case report

Introduction

Discordant lymphomas are rare entities characterized by the simultaneous presence of two distinct types of lymphomas in different anatomic sites. We describe a very rare case of simultaneous occurrence of splenic mantle cell lymphoma and marginal zone lymphoma involving the bone marrow and peripheral blood.

Case presentation

We report the case of a 60-year-old asymptomatic Caucasian woman in whom discordant lymphomas were discovered when a slight lymphocytosis and a conspicuous splenomegaly were observed. The different morphological, immunophenotypical and immunohistochemical features found in the different pathologic samples obtained from peripheral blood, bone marrow and spleen sections made it possible to differentiate two types of non-Hodgkin B-cell lymphomas: a mantle cell lymphoma infiltrating the spleen and a marginal zone lymphoma involving both the bone marrow and peripheral blood. Since a similar IgH gene rearrangement was found both in the bone marrow and in the spleen, the hypothesis of a common origin, followed by a different clonal selection of the neoplastic lymphocytes may be taken into consideration.

Conclusion

Our case emphasizes the usefulness of investigating simultaneous specimens from different anatomic sites from the same patient and the relevant diagnostic role of splenectomy.