Sunday, December 30, 2012

Treatment of diffuse large B cell lymphoma.


Treatment of diffuse large B cell lymphoma.


Dec 2012

Source

Department of Internal Medicine, Chonbuk National University Medical School, Jeonju, Korea.

Abstract


Diffuse large B cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma in all countries and all age groups. DLBCL is potentially curable, and the outcome of patients with DLBCL has completely changed with the introduction of therapy involving the monoclonal antibody rituximab in combination with chemotherapy. Nonetheless, relapse is detected after treatment with rituximab, cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisolone in approximately 30% of patients. It has recently become clear that DLBCL represents a heterogeneous admixture of quite different entities. Gene expression profiling has uncovered DLBCL subtypes that have distinct clinical behaviors and prognoses; however, incorporation of this information into treatment algorithms awaits further investigation. Future approaches to DLBCL treatment will use this new genetic information to identify potential biomarkers for prognosis and targets for treatment.

Full text article:

Tuesday, December 25, 2012

MCL1 is deregulated in subgroups of diffuse large B-cell lymphoma.


MCL1 is deregulated in subgroups of diffuse large B-cell lymphoma.


Dec 21, 2012

Source

Department of Hematology, Oncology and Tumor Immunology, Molecular Cancer Research Center, Charité - Universitätsmedizin Berlin, Germany.

Abstract


Keywords: 


MCL1, diffuse large B-cell lymphoma, aCGH, apoptosis, therapy resistance


MCL1 is an anti-apoptotic member of the BCL2 family that is deregulated in various solid and hematological malignancies. However, its role in the molecular pathogenesis of diffuse large B-cell lymphoma (DLBCL) is unclear. We analyzed gene expression profiling data from 350 DLBCL patient samples and detected that activated B-cell-like (ABC) DLBCLs express MCL1 at significantly higher levels compared to germinal center B-cell-like (GCB) DLBCL patient samples (p=2.7 x 10(-10)). Immunohistochemistry confirmed high MCL1 protein expression predominantly in ABC DLBCL in an independent patient cohort (n=249; p=0.001). To elucidate molecular mechanisms leading to aberrant MCL1 expression, we analyzed array comparative genomic hybridization (aCGH) data of 203 DLBCL samples and identified recurrent chromosomal gains/amplifications of the MCL1 locus that occurred in 26% of ABC DLBCLs. In addition, aberrant STAT3 signaling contributed to high MCL1 expression in this subtype. Knockdown of MCL1 as well as treatment with the BH3-mimetic obatoclax induced apoptotic cell death in MCL1 positive DLBCL cell lines. In summary, MCL1 is deregulated in a significant fraction of ABC DLBCLs and contributes to therapy resistance. These data suggest that specific inhibition of MCL1 might be utilized therapeutically in a subset of DLBCLs.Leukemia accepted article preview online, 21 December 2012; doi:10.1038/leu.2012.367.


Thursday, December 20, 2012

Genome sequencing reveals mutation unique to Burkitt lymphoma


Genome sequencing reveals mutation unique to Burkitt lymphoma


Nov 2012

The first broad genetic landscape map of a Burkitt lymphoma tumor has identified 70 mutations, including several not previously associated with cancer and a new one that is unique to the disease. These findings could be used to develop new drugs or aim existing therapies at mutations known to be susceptible.
Burkitt lymphoma is an aggressive form of lymphoma. This study was the first complete sequence of a Burkitt lymphoma genome, plus genes from 59 additional Burkitt cases and 94 diffuse large B cell lymphomas, which share many of the same characteristics of Burkitt lymphoma. Similarities between the malignancies can often lead to mistaken diagnoses and failed treatments.
Striking differences were found in the gene mutation pattern of Burkitt lymphomas compared with the diffuse large B cell lymphomas.
“It's important that doctors make the right diagnosis for Burkitt lymphoma, which can be cured with the correct therapies,” said Sandeep S. Dave, MD, MBA, MS, associate professor at Duke Medicine and senior author. “But if misdiagnosed and given the standard chemotherapy regimes for diffuse large B cell lymphomas, Burkitt lymphoma patients invariably relapse.”
The analysis identified 70 genes that were frequently mutated in the Burkitt lymphomas, including a number of genes that were identified in cancer for the first time. One of the newly identified gene mutations, ID3, appeared in 34% of the Burkitt cases, but was not evident in any of the diffuse large B cell lymphomas. The mutation has a silencing effect on a gene that suppresses cell growth, enabling cells to multiply.
Dave explained that this alteration alone may not cause cancer, but when it occurs along with the MYC gene mutations that are common in Burkitt lymphoma and other malignancies, it works like an accelerant to fuel tumor growth. That finding could prove helpful for developing a new drug to function like a normal ID3 gene and suppress cancer cell proliferation in lymphomas as well as numerous other cancers.
“If we can find a way to mimic ID3, restoring the function of the gene to slow the growth of tumors, this could provide a new treatment approach,” Dave said. “We have experiments that suggest this is the case, but much more research is needed. This work provides a starting point.”
These findings were published in Nature Genetics (2012; doi:10.1038/ng.2468).

Dose-densified chemoimmunotherapy followed by systemic central nervous system prophylaxis for younger high-risk diffuse large B-cell/follicular grade 3 lymphoma patients: results of a phase II Nordic Lymphoma Group study.


Dose-densified chemoimmunotherapy followed by systemic central nervous system prophylaxis for younger high-risk diffuse large B-cell/follicular grade 3 lymphoma patients: results of a phase II Nordic Lymphoma Group study.


Dec 2012

Source

Department of Oncology, Oslo University Hospital, Oslo, Norway.

Abstract


Background
Many patients with aggressive B-cell lymphomas and high clinical risk score still die of lymphoma after conventional R-CHOP chemoimmunotherapy. We hypothesized that intensified chemoimmunotherapy including systemic central nervous system (CNS) prophylaxis improves outcome and reduces the incidence of CNS-related events.Patients and methodsInclusion criteria were age 18-65 years, primary diffuse large B-cell lymphoma or grade III follicular lymphoma without clinical signs of CNS disease and negative cerebrospinal fluid cytology, age-adjusted International Prognostic Index 2-3 and WHO performance score 0-3. Treatment consisted of six courses of R-CHOEP-14 followed by a course of high-dose cytarabine and a course of high-dose methotrexate. Primary end point was failure-free survival (FFS) at 3 years.ResultsA total of 156 eligible patients with a median age of 54 years (range 20-64) were included. Three toxic deaths were observed. Three-year overall survival (OS) and FFS rates (median observation time 52 months for survivors) were 81% and 65%, respectively. Seven patients experienced CNS relapse, all within 6 months.ConclusionsThe results are promising with favorable 3-year OS and FFS rates, a low toxic death rate and a lower than expected number of CNS events. CNS progression might be further reduced by earlier CNS prophylaxis.CinicalTrials.gov. identifierNCT01502982.

Clinicopathological features of aggressive B-cell lymphomas including B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell and Burkitt lymphomas: a study of 44 patients from Argentina.


Clinicopathological features of aggressive B-cell lymphomas including B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell and Burkitt lymphomas: a study of 44 patients from Argentina.


Dec 2012

Source

Servicio de Patología, Hospital Privado de Córdoba. Córdoba, Argentina.

Abstract


Aggressive B-cell lymphomas incorporate a wide spectrum of lymphomas that pose challenges in diagnosis as well as treatment. We evaluated the clinicopathological features of 44 patients with aggressive B-cell lymphomas which were classified into 3 groups based on the World Health Organization 2008 classification as follows: including 30 cases of diffuse large B-cell lymphoma (DLBCL), 8 cases of Burkitt lymphoma (BL) and 6 cases of B-cell lymphoma, unclassifiable, with features intermediate between Burkitt lymphoma and diffuse large B-cell lymphoma (BCLU). Male predominance was observed in BL and BCLU groups and the mean age varied from 29 years in BL, 61 years in DLBCL and 70 years in BCLU. Patients with BCLU presented at more advanced stages and had a higher international prognostic index. By immunohistochemistry, they shared characteristics of both BL (including more frequent expression of SOX11) and DLBCL. FISH analyses showed three cases with more than one rearrangement: one MYC/BCL2 and two BCL2/BCL6, in addition to which one case with BCL2/IGH translocation and another with MYC rearrangement were also detected. The mean follow-up survival time of BCLU was 6.6 months, which was significantly shorter in comparison to DLBCL (31 months) and BL (30 months), respectively. The importance of recognizing this BCLU group relies on its different clinical course, poor prognosis and shorter survival than DLBCL and BL. An accurate diagnosis is critical for risk stratification and to improve therapeutic approaches and outcomes.

Elsevier - Annals of Diagnostic Pathology

Dosimetric Evaluation and Treatment Outcome of Intensity Modulated Radiation Therapy After Doxorubicin-Based Chemotherapy for Primary Mediastinal Large B-Cell Lymphoma.


Dosimetric Evaluation and Treatment Outcome of Intensity Modulated Radiation Therapy After Doxorubicin-Based Chemotherapy for Primary Mediastinal Large B-Cell Lymphoma.


Dec 2012

Source

Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences (CAMS) and Peking Union Medical College (PUMC), Beijing, P. R. China.

Abstract


PURPOSE:

The value of intensity-modulated radiation therapy (IMRT) after doxorubicin-based chemotherapy in primary mediastinal large B-cell lymphoma (PMBCL) is unknown. We assessed the dosimetric parameters, treatment outcomes, and toxicity of IMRT in PMBCL.

METHODS AND MATERIALS:

Forty-one PMBCL patients underwent mediastinal IMRT after doxorubicin-based chemotherapy. Thirty-eight patients had stage I-II disease, and 3 patients had stage III-IV disease. Most patients presented with bulky mediastinal disease (65.9%) and local invasion (82.9%). The dose-volume histograms of the target volume and critical normal structures were evaluated.

RESULTS:

The average planning target volume (PTV) mean dose was 39 Gy. Only 0.5% and 1.4% of the PTV received <90% and <95% of the prescribed dose, respectively, indicating excellent target coverage. The median mean lung dose and percentage lung volume receiving 20 Gy (V20) were 16.3 Gy and 30.6%. The 5-year overall survival (OS) and local control (LC) were 95.1% and 89.8%. After chemotherapy, consolidation radiation therapy in patients with complete/partial response resulted in significantly better survival than salvage radiation therapy in patients with stable/progressive disease (3-year OS 100% vs 75%; 3-year LC 96.6% vs 62.5%). No grade 4 or 5 acute or late toxicities occurred.

CONCLUSIONS:

Mediastinal IMRT after doxorubicin-based chemotherapy can be safely and efficiently delivered, and it provides favorable outcomes in PMBCL patients with a large target volume and high-risk features.

Lenalidomide in diffuse large B-cell lymphoma


Lenalidomide in diffuse large B-cell lymphoma.


2012

Source

Hematology and Oncology Department, Hôpital Saint-Louis, AP-HP and IUH, INSERM U728, University Paris VII, 75010 Paris, France.

Abstract


Diffuse large B-cell lymphoma (DLBCL) is the most common form of non-Hodgkin's lymphoma (NHL) in adults. Even if the natural history of DLBCL has been improved with the advent of immunochemotherapy, the survival results obtained with current treatment options clearly indicate that new agents or novel approaches are needed. Lenalidomide (Revlimid, Celgene Corporation, Summit, NJ, USA), an analogue of thalidomide, is an immunomodulatory drug with pleiotropic mechanisms of action potentially adding to immunochemotherapy. We present here the biological rational for the use of lenalidomide in DLBCL in light of recent advances in the pathophysiology of the disease and the therapeutic results of the most recent trials published in literature or reported in meetings in relapsed/refractory situations as well as in first-line treatment.

Thursday, December 13, 2012

Is there any role for transplantation in the rituximab era for diffuse large B-cell lymphoma?


Is there any role for transplantation in the rituximab era for diffuse large B-cell lymphoma?


2012

Source

1Hospital Saint Louis, Paris Diderot University, Paris, France.

Abstract


Salvage chemotherapy followed by high-dose therapy and autologous stem cell transplantation is the standard of treatment for chemosensitive relapses in diffuse large B-cell lymphoma. The addition of rituximab to chemotherapy has improved the response rate and failure-free survival after first-line treatment and relapses. Fewer relapses are expected, although there is no consensus on the best salvage regimen. The intergroup Collaborative Trial in Relapsed Aggressive Lymphoma (CORAL) set the limits for this standard of treatment after first comparing 2 salvage regimens: rituximab, ifosfamide, etoposide, and carboplatin (R-ICE) and rituximab, dexamethasone, aracytine, and cisplatin (R-DHAP). There was no difference in response rates or survivals between these salvage regimens. Several factors affected survival: prior treatment with rituximab, early relapse (< 12 months), and a secondary International Prognostic Index score of 2-3. For patients with 2 factors, the response rate to salvage was only 46%, which identified easily a group with poor outcome. Moreover, patients with an ABC subtype or c-MYC translocation responded poorly to treatment. More than 70% of patients will not benefit from standard salvage therapy, and continued progress is needed. Studies evaluating immunotherapy after transplantation, including allotransplantation, new conditioning regimens with radioimmunotherapy and other combinations of chemotherapy based on diffuse large B-cell lymphoma subtype, are discussed herein. Early relapses and/or patients refractory to upfront rituximab-based chemotherapy have a poor response rate and prognosis. A better biological understanding of these patients and new approaches are warranted.

Sunday, December 2, 2012

Diffuse large B-cell lymphoma in human T-lymphotropic virus type 1 carriers.


Diffuse large B-cell lymphoma in human T-lymphotropic virus type 1 carriers.


2012

Source

Department of Oncology and Radiotherapy, Edgardo Rebagliati Martins Hospital, Lima, Peru.

Abstract


We describe the clinical and pathological characteristics of seven patients who were human T-lymphotropic virus type 1 (HTLV-1) carriers and had a pathological diagnosis of de novo diffuse large B-cell lymphoma. Interestingly, three of our cases showed positive expression of Epstein-Barr-virus, (EBV-) encoded RNA within the tumor cells indicating a possible interaction between these two viruses. Furthermore, our three EBV-positive cases presented with similar clinical characteristics such as early clinical stage and low-risk indices. To the best of our knowledge, this is the first case series describing the characteristics of HTLV-1-positive DLBCL patients. The potential relationship between HTLV-1 and EBV should be further explored.