Mantle cell lymphoma: 2012 update on diagnosis, risk-stratification, and clinical management

Mantle cell lymphoma: a rare cause of a solitary duodenal mass

Mantle cell lymphoma is a very aggressive lymphoma with a very poor prognosis. It commonly involves the gastrointestinal tract but rarely presents as primary gastrointestinal lymphoma. The most notable cases of primary gastrointestinal mantle cell lymphomas have been described as multiple lymphomatous polyposis and have a very poor prognosis. We report a case of primary gastrointestinal mantle cell lymphoma that was discovered by endoscopic biopsy of a single duodenal polyp in a 70-year-old woman who was previously treated for Helicobacter pylori gastritis. She presented with a 6-month history of indigestion, heartburn and abdominal bloating. A subsequent workup revealed one extranodal site of involvement, lymphatic involvement below the diaphragm and a normal bone marrow biopsy. We followed a wait-and-watch approach including serial CT scans and blood tests. Two years later, her symptoms have not progressed and her disease has remained stable.

Clinical features and treatment outcomes in patients with mantle cell lymphoma in Korea: Study by the Consortium for Improving Survival of Lymphoma

Background

We investigated the clinical features and treatment outcomes of patients with mantle cell lymphoma (MCL) in Korea.

Methods

We retrospectively analyzed the clinical characteristics and prognosis of 131 patients diagnosed with MCL between January 2004 and December 2009 at 15 medical centers in Korea; all patients received at least 1 chemotherapeutic regimen for MCL.

Results

The median age for the patients was 63 years (range, 26-78 years), and 77.9% were men. A total of 105 patients (80.1%) had stage III or IV MCL at diagnosis. Fifty-two patients (39.7%) were categorized with high- or high-intermediate risk MCL according to the International Prognostic Index (IPI). Eighteen patients (13.7%) were in the high-risk group according to the simplified MCL-IPI (MIPI). The overall incidence of extranodal involvement was 69.5%. The overall incidence of bone marrow and gastrointestinal involvements at diagnosis was 41.2% and 35.1%, respectively. Cyclophosphamide, doxorubicin, vincristine, prednisolone, and rituximab were used frequently as the first-line treatment (41.2%). With a median follow-up duration of 20.0 months (range, 0.2-77.0 months), the overall survival (OS) at 2 years was 64.7%, while the event-free survival (EFS) was 39.7%. Multivariate analysis showed that the simplified MIPI was significantly associated with OS. However, the use of a rituximab-containing regimen was not associated with OS and EFS.

Conclusion

Similar to results from Western countries, the current study found that simplified MIPI was an important prognostic factor in Korean patients with MCL.

Identification of B-cell lymphoma subsets by plasma protein profiling using recombinant antibody microarrays

B-cell lymphoma (BCL) heterogeneity represents a key issue, often making the classification and clinical management of these patients challenging. In this pilot study, we outlined the first resolved view of BCL disease heterogeneity on the protein level by deciphering disease-associated plasma biomarkers, specific for chronic lymphocytic leukemia, diffuse large B-cell lymphoma, follicular lymphoma, and mantle cell lymphoma, using recombinant antibody microarrays targeting mainly immunoregulatory proteins. The results showed the BCLs to be heterogeneous, and revealed potential novel subgroups of each BCL. In the case of diffuse large B-cell lymphoma, we also indicated a link between the novel subgroups and survival.

Management perspective for mantle cell lymphoma

SUMMARY Mantle cell lymphoma (MCL) is genetically characterized by the t(11;14) (q13;q32) translocation resulting in the overexpression of cyclin D1. It generally has an aggressive clinical course with a poor prognosis. However, there is now a recognized subgroup with clinically indolent MCL. Management of MCL can be challenging. Early recognition of young and fit patients for potential intensive therapy and autologous stem cell transplant is important. Combination of rituximab with high-dose cytarabine should be used in upfront therapy for appropriate patients. In elderly and/or less fit patients, chemoimmunotherapy may be considered. Novel agents offer promising potential in the management of MCL and are likely to change the way it is treated.

Landscape of somatic mutations and clonal evolution in mantle cell lymphoma

Mantle cell lymphoma (MCL) is an aggressive tumor, but a subset of patients may follow an indolent clinical course. To understand the mechanisms underlying this biological heterogeneity, we performed whole-genome and/or whole-exome sequencing on 29 MCL cases and their respective matched normal DNA, as well as 6 MCL cell lines. Recurrently mutated genes were investigated by targeted sequencing in an independent cohort of 172 MCL patients. We identified 25 significantly mutated genes, including known drivers such as ataxia-telangectasia mutated (ATM), cyclin D1 (CCND1), and the tumor suppressor TP53; mutated genes encoding the anti-apoptotic protein BIRC3 and Toll-like receptor 2 (TLR2); and the chromatin modifiers WHSC1, MLL2, and MEF2B. We also found NOTCH2 mutations as an alternative phenomenon to NOTCH1 mutations in aggressive tumors with a dismal prognosis. Analysis of two simultaneous or subsequent MCL samples by whole-genome/whole-exome (n = 8) or targeted (n = 19) sequencing revealed subclonal heterogeneity at diagnosis in samples from different topographic sites and modulation of the initial mutational profile at the progression of the disease. Some mutations were predominantly clonal or subclonal, indicating an early or late event in tumor evolution, respectively. Our study identifies molecular mechanisms contributing to MCL pathogenesis and offers potential targets for therapeutic intervention.

The use of salivary protein secretions as an in vivo model to study Mantel cell lymphoma progression and treatment

PURPOSE

The objective of this study was to compare the salivary protein profiles from an individual diagnosed with MCL before, during, and after chemotherapy.

METHODS

Saliva specimens acquire prior, during, and after chemotherapy. Specimens were analyzed using a LC-MS/MS mass spectrometer.

RESULTS

The results of the study suggest salivary protein alterations secondary to MCL and that a number of the proteins were changed as a result of chemotherapeutic intervention suggesting that the treatment, from a proteomic perspective, was efficacious. The study suggests that salivary secretions may be used as in vivo model for studying MCL progression and treatment efficacy.

Sex- and subtype-specific analysis of H2AFX polymorphisms in non-Hodgkin lymphoma

H2AFX encodes a histone variant involved in signaling sites of DNA damage and recruiting repair factors. Genetic variants in H2AFX may influence risk of non-Hodgkin lymphoma (NHL), a heterogeneous group of lymphoid tumors that are characterized by chromosomal translocations. We previously reported that rs2509049, a common variant in the promoter of H2AFX, was associated with risk for NHL in the British Columbia population. Here we report results for 13 single nucleotide polymorphisms (SNPs) in 100 Kb surrounding H2AFX in an expanded collection of 568 NHL cases and 547 controls. After correction for multiple testing, significant associations were present for mantle cell lymphoma (p=0.007 for rs604714) and all B-cell lymphomas (p=0.046 for rs2509049). Strong linkage disequilibrium in the 5 Kb upstream of H2AFX limited the ability to determine which specific SNP (rs2509049, rs7759, rs8551, rs643788, rs604714, or rs603826), if any, was responsible. There was a significant interaction between sex and rs2509049 in the all B-cell lymphomas group (p=0.002); a sex-stratified analysis revealed that the association was confined to females (p=0.001). Neither the overall nor the female-specific association with rs2509049 was replicated in any of four independent NHL sample sets. Meta-analysis of all five study populations (3,882 B-cell NHL cases and 3,718 controls) supported a weak association with B-cell lymphoma (OR=0.92, 95% CI=0.86-0.99, p=0.034), although this association was not significant after exclusion of the British Columbia data. Further research into the potential sex-specificity of the H2AFX-NHL association may identify a subset of NHL cases that are influenced by genotype at this locus.

Cyclin D1 (CCND1) messenger RNA expression as assessed by real-time PCR contributes to diagnosis and follow-up control in patients with mantle cell lymphoma

Molecular diagnosis of mantle cell lymphoma (MCL) can be difficult because the t(11;14)/IGH@-CCND1 is extremely heterogeneous at the DNA level. Aiming to establish a reliable molecular tool that could be easily implemented in routine diagnostics, we developed a new real-time polymerase chain reaction (PCR) assay for CCND1 expression measurement and evaluated 451 cases: 142 MCL, 76 chronic lymphocytic leukemia, 20 hairy cell leukemia, 13 hairy cell leukemia-variant, 20 splenic marginal zone lymphoma, 91 other mature B-cell neoplasms, 29 other hematologic neoplasms, and 60 healthy individuals. Sensitivity of the real-time PCR assay was up to 10(-4). In t(11;14)/IGH@-CCND1 positive lymphoma samples (n = 150), median %CCND1/ABL1 expression level was 178.2 (range: 1.5-4, 152.0). Normalized by t(11;14)/IGH@-CCND1 positive cells as determined by fluorescence in situ hybridization IGH@-CCND1 positive samples showed a median %CCND1/ABL1 of 445.8 (range: 17.9-4,848.5). A normalized %CCND1/ABL1 expression of at least 17.0 was chosen as threshold for CCND1 positivity. For unnormalized samples, the positive detection rate of t(11;14)/IGH@-CCND1 by CCND1 expression was 87.3%. Healthy individuals had low %CCND1/ABL1 (median, 1.1; range, 0.0-7.8). The negative predictive value for exclusion of a t(11;14)/IGH@-CCND1 by CCND1 expression was 95.3% by the above threshold. %CCND1/ABL1 was higher in MCL than in the remaining B-cell lymphomas (mean ± SD, 392.9 ± 685.3 vs. 46.0 ± 305.0; p < 0.001). In 66 follow-up samples, CCND1 showed 2.5-3.5 log reduction after chemotherapy and increase at relapse. CCND1 expression could serve as adjunct to other techniques in diagnosis and follow-up of B-cell lymphomas.

Single-agent lenalidomide in patients with mantle-cell lymphoma who relapsed or progressed after or were refractory to bortezomib: phase II MCL-001 (EMERGE) study

PURPOSE

Although dose-intensive strategies or high-dose therapy induction followed by autologous stem-cell transplantation have improved the outcome for patients with mantle-cell lymphoma (MCL), most eventually relapse and subsequently respond poorly to additional therapy. Bortezomib (in the United States) and temsirolimus (in Europe) are currently the only two treatments approved for relapsed disease. Lenalidomide is an immunomodulatory agent with proven tumoricidal and antiproliferative activity in MCL. The MCL-001 (EMERGE) trial is a global, multicenter phase II study examining the safety and efficacy of lenalidomide in patients who had relapsed or were refractory to bortezomib.

PATIENTS AND METHODS

Lenalidomide 25 mg orally was administered on days 1 through 21 every 28 days until disease progression or intolerance. Primary end points were overall response rate (ORR) and duration of response (DOR); secondary end points included complete response (CR) rate, progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

In all, 134 patients were enrolled with a median age of 67 years and a median of four prior therapies (range, two to 10 prior therapies). The ORR was 28% (7.5% CR/CR unconfirmed) with rapid time to response (median, 2.2 months) and a median DOR of 16.6 months (95% CI, 7.7 to 26.7 months). Median PFS was 4.0 months (95% CI, 3.6 to 5.6 months), and median OS was 19.0 months (95% CI, 12.5 to 23.9 months). The most common grade 3 to 4 adverse events were neutropenia (43%), thrombocytopenia (28%), anemia (11%), pneumonia (8%), and fatigue (7%).

CONCLUSION

The MCL-001 study demonstrated durable efficacy of lenalidomide with a predictable safety profile in heavily pretreated patients with MCL who had all relapsed or progressed after or were refractory to bortezomib.

Mantle cell lymphoma and involvement of the orbit and ocular adnexa

Orbital and ocular adnexal lymphomas are rare and represent around 1-2% of lymphomas and about 8% of the extranodal lymphomas. However, these entities represent the majority of orbital malignancies. Lymphomas of the ocular adnexal region are primary or secondary lymphomas, and the majority of them are composed of small, mature lymphocytes, which provide a large differential diagnosis. Thus, these entities are not easily distinguished from indolent lymphoid processes such as reactive lymphoid hyperplasia. Extranodal marginal zone lymphoma is the most common lymphoma in the ocular adnexal region. However, this entity cannot be distinguished from benign lymphoid proliferations or other lymphomas composed of small, mature lymphocytes by routine histopathology. We describe a 78-year-old man who presents with bilateral upper eyelid masses, which had been present and grew in size over the past twelve months prior to his presentation. A biopsy of the mass shows a monotonous population of small, mature lymphocytes. The immunohistochemical studies performed on the eyelid mass confirmed a monoclonal proliferation of B cells expressing cyclin-D1; therefore, a final diagnosis of mantle cell lymphoma was rendered. A literature review of mantle cell lymphoma with orbital and ocular adnexal involvement and the diagnostic pitfalls in this area of hematopathology are discussed.

Mantle cell lymphoma relapsing at the lymphedematous arm

Lymphedema (LE) is a chronic medical condition characterized by lymphatic fluid retention, resulting in tissue swelling. Cancer treatments involving lymph nodes can damage lymph drainage routes, causing accumulation of lymph fluid in the interstitial tissue of related limbs and body areas and secondary LE. Basically, the LE has a negative impact on physical and mental quality of life. Moreover, 0.07-0.04% of long term survivors (most patients undergoing mastectomy) can develop the Stewart-Treves syndrome, a rare and aggressive multifocal lymphangiosarcoma arising within the LE region. Here we describe the case of a 45-year-old woman with a massive LE of the left arm, as a consequence of previous breast cancer, who was diagnosed after 4 years of stage IV mantle cell lymphoma (MCL). The patient, after obtaining complete remission with chemotherapy and autologous hematopoietic stem cell transplant, had a relapse of MCL in the lymphedema site.

Open questions in the management of mantle cell lymphoma

Mantle cell lymphoma (MCL) is one of the lymphomas with the worse prognosis (median survival 3-5years) as it has an aggressive evolution and at the same time is incurable. Biologically it is characterized by the t(11;14)(q13;q32) translocation leading to overexpression of cyclin D1. This review focuses on a number of controversial issues in the management of this disease, as how to stage patients with a disease which often has extranodal localizations, how to recognize the small subgroup of cases with an indolent course, which treatment is suggested for the young and fit or for the elderly, the role of CNS prophylaxis, rituximab maintenance and radiotherapy, the indications to allogeneic transplantation and the place of new active anti-lymphoma drugs.

DNA Methylation of Tumor Suppressive miRNAs in Non-Hodgkin's Lymphomas

DNA methylation is an epigenetic alteration leading to heritable phenotypic changes of cells with functional consequences. It is important in early embryonic development, stem cell differentiation, and tissue-specific gene expression. In normal cells, promoter-associated CpG islands (CGI) are generally unmethylated except in X-chromosome inactivation or genomic imprinting. In cancer, tumor cells are characterized by global hypomethylation but locus-specific hypermethylation of promoter-associated CGI, resulting in gene silencing. MicroRNAs (miRNAs) are short, non-coding RNA sequences of 18-25 nucleotides, which can repress the translational of multiple protein-coding mRNAs by sequence-specific binding to the 3'untranslated region. Depending on the genes targeted, miRNA can be tumor suppressive if an oncogene is repressed, or it can be oncogenic when a tumor suppressive gene is repressed. Recently, aberrant methylation of tumor suppressive miRNAs has been reported in different types of cancers including lymphomas. Herein, we review the recent literature of methylation of tumor suppressive miRNAs in different histopathologic subtypes of lymphomas, and discuss its potential diagnostic, prognostic, and therapeutic significance.