Classical Hodgkin's lymphoma shows epigenetic features of abortive plasma cell differentiation

Background

Epigenetic changes are involved in the extinction of the B-cell gene expression program of classical Hodgkin’s lymphoma. However, little is known regarding epigenetic similarities between cells of classical Hodgkin’s lymphoma and plasma cell myeloma, both of which share extinction of the gene expression program of mature B cells.

Design and Methods

Global histone H3 acetylation patterns were determined in cell lines derived from classical Hodgkin’s lymphoma, plasma cell myeloma and B-cell lymphoma by chromatin immunoprecipitation and subsequent hybridization onto promoter tiling arrays. H3K27 trimethylation was analyzed by chromatin immunoprecipitation and real-time DNA polymerase chain reaction for selected genes. Epigenetic modifications were compared to gene expression data.

Results

Characteristic B-cell genes were hypoacetylated in classical Hodgkin’s lymphoma and plasma cell myeloma cell lines as demonstrated by comparison of their histone H3 acetylation patterns to those of B-cell lines. However, the number of genes jointly hyperacetylated and expressed in classical Hodgkin’ lymphoma and plasma cell myeloma cell lines, such as IRF4/MUM1 and RYBP, is limited. Moreover, H3K27 trimethylation for selected characteristic B-cell genes revealed that this additional epigenetic silencing is much more prevalent in classical Hodgkin’s lymphoma than in plasma cell myeloma.

Conclusions

Our epigenetic data support the view that classical Hodgkin’s lymphoma is characterized by abortive plasma cell differentiation with a down-regulation of characteristic B-cell genes but without activation of most genes typical of plasma cells.     

Methylation profiling of mediastinal gray zone lymphoma reveals a distinctive signature with elements shared by classical Hodgkin's lymphoma and primary mediastinal large B-cell lymphoma

Background

Mediastinal gray zone lymphoma is a newly recognized entity with transitional morphological and immunophenotypic features between the nodular sclerosis subtype of Hodgkin’s lymphoma and primary mediastinal large B-cell lymphoma. Diagnostic criteria for mediastinal gray zone lymphoma are still challenging, and the optimal therapy is as yet undetermined. Epigenetic changes have been implicated in the loss of the B-cell program in classical Hodgkin’s lymphoma, and might provide a basis for the immunophenotypic alterations seen in mediastinal gray zone lymphoma.

Design and Methods

We performed a large-scale DNA methylation analysis of microdissected tumor cells to investigate the biological underpinnings of mediastinal gray zone lymphoma and its association with the related entities classical Hodgkin’s lymphoma and primary mediastinal large B-cell lymphoma, making comparisons with the presumptively less related diffuse large B-cell lymphoma.

Results

Principal component analysis demonstrated that mediastinal gray zone lymphoma has a distinct epigenetic profile intermediate between classical Hodgkin’s lymphoma and primary mediastinal large B-cell lymphoma but remarkably different from that of diffuse large B-cell lymphoma. Analysis of common hypo- and hypermethylated CpG targets in mediastinal gray zone lymphoma, classical Hodgkin’s lymphoma, primary mediastinal large B-cell lymphoma and diffuse large B-cell lymphoma was performed and confirmed the findings of the principal component analysis. Based on the epigenetic profiles we were able to establish class prediction models utilizing genes such as HOXA5, MMP9, EPHA7 and DAPK1 which could distinguish between mediastinal gray zone lymphoma, classical Hodgkin’s lymphoma and primary mediastinal large B-cell lymphoma with a final combined prediction of 100%.

Conclusions

Our data confirm a close relationship between mediastinal gray zone lymphoma and both classical Hodgkin’s lymphoma and primary mediastinal large B-cell lymphoma. However, important differences were observed as well, allowing a clear distinction from both parent entities. Thus, mediastinal gray zone lymphoma cannot be assigned to either classical Hodgkin’s lymphoma or primary mediastinal large B-cell lymphoma, validating the decision to create an intermediate category in the World Health Organization classification.     

Tumor-infiltrating macrophages correlate with adverse prognosis and Epstein-Barr virus status in classical Hodgkin's lymphoma

Background

Classical Hodgkin’s lymphoma is characterized by a minority of neoplastic cells surrounded by a heterogeneous background population of non-neoplastic cells including lymphoma-associated macrophages. High levels of expression of both the monocyte/macrophage lineage-associated antigens CD68 and CD163 have been suggested to have pro-tumor effects. The aim of our study was to correlate expression of CD68 and CD163 with the clinico-pathological features and prognosis of a cohort of patients with previously untreated Hodgkin’s lymphoma.

Design and Methods

A tissue microarray was constructed from paraffin-embedded tumor tissues from 288 cases of classical Hodgkin’s lymphoma. CD68 and CD163 expression was assessed immunohistochemically and the degree of macrophage infiltration within the tumor was scored using point grid counting. Clinical data were obtained from clinical records.

Results

The patients’ median age was 37 years (range, 6–86 years). The male to female ratio was 1.2. In classical Hodgkin’s lymphoma (n = 288) high CD68 and CD163 expression correlated, at the univariate level, with poorer overall survival (P=0.002 and P=0.03, respectively) and event-free survival (P=0.03 and P=0.04, respectively). At the multivariate level, high CD68 expression remained significantly predictive of overall survival (P=0.004). In addition, we demonstrated that both high CD68 and CD163 expression were associated with the presence of Epstein-Barr virus in the neoplastic cells (P=0.001 and P=0.0002, respectively).

Conclusions

In classical Hodgkin’s lymphoma, high expression of the macrophage/monocyte-related antigens CD68 and CD163 correlates with adverse outcome and with the presence of Epstein-Barr virus in the tumor cell population.     

Second-line salvage chemotherapy for transplant-eligible patients with Hodgkin's lymphoma resistant to platinum-containing first-line salvage chemotherapy

Background

The management of patients with relapsed or refractory Hodgkin’s lymphoma who achieve less than a partial response to first-line salvage chemotherapy is unclear. The objective of this study was to evaluate response and outcomes to second-line salvage and autologous stem cell transplantation in patients not achieving a complete or partial response to platinum-containing first-line salvage chemotherapy.

Design and Methods

Consecutively referred transplant-eligible patients with relapsed/refractory Hodgkin’s lymphoma after primary chemotherapy received gemcitabine, dexamethasone, and cisplatin as first salvage chemotherapy. Those achieving a complete or partial response, and those with a negative gallium scan and stable disease with bulk <5 cm proceeded to high-dose chemotherapy and autologous stem cell transplantation. Patients with progressive disease or stable disease with a positive gallium scan or bulk ≥5 cm were given second salvage chemotherapy with mini-BEAM (carmustine, etoposide, cytarabine, melphalan). Patients who responded (according to the same definition) proceeded to autologous stem cell transplantation.

Results

One hundred and thirty-one patients with relapsed/refractory Hodgkin’s lymphoma received first-line salvage gemcitabine, dexamethasone, and cisplatin; of these patients 99 had at least a partial response (overall response rate 76%). One hundred and twelve (85.5%) patients proceeded to autologous stem cell transplantation, while the remaining 19 (14.5%) patients received mini-BEAM. Among these 19 patients, six had at least a partial response (overall response rate 32%), and nine proceeded to autologous stem cell transplantation. The remaining ten patients received palliative care. Seven of the nine patients transplanted after mini-BEAM had a subsequent relapse. Patients receiving second salvage mini-BEAM had poor outcomes, with a 5-year progression-free survival rate of 11% and a 5-year overall survival rate of 20%.

Conclusions

Patients who require a second salvage regimen to achieve disease control prior to autologous stem cell transplantation have a relatively poor outcome and should be considered for alternative treatment strategies.     

Expression of the c-Met oncogene by tumor cells predicts a favorable outcome in classical Hodgkin's lymphoma

Background

The c-Met signaling pathway regulates a variety of biological processes, including proliferation, survival and migration. Deregulated c-Met activation has been implicated in the pathogenesis and prognosis of many human malignancies. We studied the function and prognostic significance of c-Met and hepatocyte growth factor protein expression in patients with classical Hodgkin’s lymphoma.

Design and Methods

Expression of c-Met and its ligand, hepatocyte growth factor, were determined by immunohistochemistry. Prognostic values were defined in cohorts of German and Dutch patients with classical Hodgkin’s lymphoma. Functional studies were performed on Hodgkin’s lymphoma cell lines.

Results

Expression of c-Met was detected in the tumor cells of 52% (80/153) of the patients and expression of its ligand, hepatocyte growth factor, in 8% (10/121) of the patients. c-Met expression correlated with a 5-year freedom from tumor progression of 94%, whereas lack of expression correlated with a 5-year freedom from tumor progression of 73% (P<0.001) in the combined cohort. In multivariate analysis both c-Met (hazard ratio 5.0, 95% confidence interval 1.9–13.3, P<0.001) and stage (hazard ratio 2.8, 95% confidence interval 1.2–6.4, P=0.014) were independent predictors for freedom from tumor progression. In functional studies activation with hepatocyte growth factor did not affect cell growth, while the c-Met inhibitor SU11274 suppressed cell growth by inducing G2/M cell cycle arrest.

Conclusions

Although functional studies showed an oncogenic role of the hepatocyte growth factor/c-Met signaling pathway in cell cycle progression, expression of c-Met in tumor cells from patients with classical Hodgkin’s lymphoma strongly correlated with a favorable prognosis in two independent cohorts.     

Peripheral blood lymphocyte/monocyte ratio at diagnosis and survival in classical Hodgkin's lymphoma

Background

Lymphopenia and tumor-associated macrophages are negative prognostic factors for survival in classical Hodgkin’s lymphoma. We, therefore, studied whether the peripheral blood absolute lymphocyte count/absolute monocyte count ratio at diagnosis affects survival in classical Hodgkin’s lymphoma.

Design and Methods

We studied 476 consecutive patients with classical Hodgkin’s lymphoma followed at the Mayo Clinic from 1974 to 2010. Receiver operating characteristic curves and area under the curve were used to determine cut-off values for the absolute lymphocyte count/absolute monocyte count ratio at diagnosis, while proportional hazards models were used to compare survival based on the absolute lymphocyte count/absolute monocyte count ratio at diagnosis.

Results

The median follow-up period was 5.6 years (range, 0.1–33.7 years). An absolute lymphocyte count/absolute monocyte count ratio at diagnosis of 1.1 or more was the best cut-off value for survival with an area under the curve of 0.91 (95% confidence interval, 0.86 to 0.96), a sensitivity of 90% (95% confidence interval, 85% to 96%) and specificity of 79% (95% confidence interval, 73% to 88%). Absolute lymphocyte count/absolute monocyte count ratio at diagnosis was an independent prognostic factor for overall survival (hazard ratio, 0.18; 95% confidence interval, 0.08 to 0.38, P<0.0001); lymphoma-specific survival (hazard ratio, 0.10; 95% confidence interval, 0.04 to 0.25, P<0.0001); progression-free survival (hazard ratio, 0.35; 95% confidence interval, 0.18 to 0.66, P<0.002) and time to progression (hazard ratio, 0.27; 95% confidence interval, 0.17 to 0.57, P<0.0006).

Conclusions

The ratio of absolute lymphocyte count/absolute monocyte count at diagnosis is an independent prognostic factor for survival and provides a single biomarker to predict clinical outcomes in patients with classical Hodgkin’s lymphoma.     

Positron emission tomography response at the time of autologous stem cell transplantation predicts outcome of patients with relapsed and/or refractory Hodgkin's lymphoma responding to prior salvage therapy

Background

High-dose chemotherapy followed by autologous stem cell transplantation is the standard treatment for relapsed and/or refractory Hodgkin’s lymphoma although half of patients relapse after transplantation. Predictive factors, such as relapse within 12 months, Ann-Arbor stage at relapse, and relapse in previously irradiated fields are classically used to identify patients with poor outcome. Recently, 18-fluorodeoxyglucose positron emission tomography has emerged as a new method for providing information to predict outcome. The aim of this study was to confirm the predictive value of positron emission tomography status after salvage therapy and to compare single versus tandem autologous stem cell transplantation in patients with relapsed and/or refractory Hodgkin’s lymphoma.

Design and Methods

We report a series of 111 consecutive patients with treatment-sensitive relapsed and/or treatment-refractory Hodgkin’s lymphoma who achieved complete (positron emission tomography-negative group) or partial remission (positron emission tomography-positive group) at positron emission tomography evaluation after salvage chemotherapy and who underwent single or tandem autologous stem cell transplantation.

Results

Five-year overall and progression-free survival rates were 81% and 64%, respectively. There were significant differences in 5-year progression-free survival (79% versus 23%; P<0.001) and 5-year overall survival (90% versus 55%, P=0.001) between the positron emission tomography-negative and -positive groups, respectively. A complete response, as determined by positron emission tomography evaluation, after salvage therapy predicted significantly better 5-year overall survival rates in both intermediate (91% versus 50%; P=0.029) and unfavorable (89% versus 58%; P=0.026) risk subgroup analyses. In the positron emission tomography-positive subgroup, tandem transplantation improved 5-year progression-free survival from 0% (in the single transplantation group) to 43% (P=0.034). Multivariate analysis showed that positron emission tomography status (hazard ratio: 5.26 [2.57–10.73]) and tandem transplantation (hazard ratio: 0.39 [0.19–0.78]) but not risk factors at relapse (hazard ratio: 1.77 [0.80–3.92]) significantly influenced progression-free survival, while only tomography status significantly influenced overall survival (hazard ratio: 4.03 [1.38–11.75]).

Conclusions

In patients with relapsed/refractory Hodgkin’s lymphoma responding to prior salvage therapy, positron emission tomography response at time of autologous stem cell transplantation favorably influences outcome and enables identification of patients requiring single or tandem transplantation.     

Sperm quality before treatment in patients with early stage Hodgkin’s lymphoma enrolled in EORTC-GELA Lymphoma Group trials

Background

Although widely recommended, cryopreservation of sperm is sometimes not performed for patients with Hodgkin’s lymphoma because of presumed poor sperm quality related to the disease. We investigated sperm quality and factors determining it in untreated patients with early stage Hodgkin’s lymphoma.

Design and Methods

Of 2362 males who participated in EORTC H6–H9 trials, 474 (20%) had data available. Sperm quality was defined according to World Health Organization guidelines. Determining factors were studied by logistic regression analysis.

Results

The median sperm concentration was 40×10⁶/mL (range, 0–345×10⁶/mL) and the median motility 50% (range, 0–90%). Sperm quality was good (concentration ≥20×10⁶/mL and motility ≥50%), intermediate (concentration ≥5×10⁶/mL) and poor (concentration <5×10⁶/mL but >0) in 41%, 49% and 7% of patients, respectively. Three percent of the patients were azoospermic. No relation was found between sperm quality and age or clinical stage of the Hodgkin’s lymphoma, but B-symptoms and elevated erythrocyte sedimentation rate predicted poor sperm quality. The odds ratios for the association of poor sperm quality with the variables examined were: presence of B-symptoms, 2.77 (95% CI, 1.50–5.12; p=0.001); erythrocyte sedimentation rate of 50 mm/h or greater, 2.35 (95% CI, 1.24–4.43; p=0.009); fever, 3.22 (95% CI, 1.41–7.33; p=0.005), and night sweats, 3.78 (95% CI, 1.97–7.26; p<0.001). There was no relation between sperm quality and pre-treatment follicle stimulating hormone level.

Conclusions

In this large study of males with Hodgkin’s lymphoma, 90% had good or intermediate sperm quality. Three percent were azoospermic. There was an association between sperm quality and the presence or absence of B-symptoms, in particular fever and night sweats. With modern fertilization techniques, in most patients with early-stage Hodgkin’s lymphoma sperm quality before treatment is good enough for future fatherhood.     

Utility of bone marrow biopsy at diagnosis in pediatric Hodgkin��s lymphoma

Background

Bone marrow biopsy is considered essential for the staging and risk-adapted treatment of Hodgkin’s lymphoma with unfavorable risk features. We reviewed the cases of pediatric Hodgkin’s lymphoma in our institution to determine the impact of bone marrow involvement on treatment, relapse, and survival.

Design and Methods

We reviewed the clinical characteristics and outcome of 383 patients treated for Hodgkin’s lymphoma at St. Jude Children’s Research Hospital between August 1990 and August 2008. The 5-year survival estimates for patients with and without bone marrow involvement were compared.

Results

Of 228 patients who had a bone marrow biopsy at diagnosis, 21 had bone marrow involvement. Bone marrow findings changed the disease stage in only seven patients (3.1%): from IB to IVB (n=1), from IIA (with bulky disease) to IVA (n=1), from IIB to IVB (n=1), and from IIIB to IVB (n=4). One patient’s risk assignment changed from intermediate to unfavorable risk without his chemotherapy being altered. No statistically significant difference was observed between patients with stage IV Hodgkin’s lymphoma who did (n=21) and did not (n=61) have bone marrow involvement in 5-year relapse-free survival (89.6± 7% versus 73.9±6.1%; P=0.25) or 5-year overall survival (95.2±8.2% versus 87.3±4.9%; P=0.82).

Conclusions

Although bone marrow involvement changed the stage in 3.1% of pediatric Hodgkin’s lymphoma patients, it did not change risk-adapted treatment or prognosis. We conclude that bone marrow biopsy need not be performed at diagnosis in patients who have unfavorable risk features, although this finding should be confirmed by larger prospective studies.     

Different response to salvage chemotherapy but similar post-transplant outcomes in patients with relapsed and refractory Hodgkin��s lymphoma

Background

The use of high-dose chemotherapy and autologous stem-cell transplantation in patients with relapsed Hodgkin’s lymphoma is supported by two randomized clinical trials but its benefit in patients with primary refractory disease is less clear. Aiming to shed light on this issue, we analyzed and compared the outcomes of patients with relapsed or refractory Hodgkin’s lymphoma treated with second-line chemotherapy and planned autologous stem-cell transplantation.

Design and Methods

We retrospectively analyzed data on 157 consecutive patients with Hodgkin’s lymphoma referred to our institution for consideration of autologous stem-cell transplantation between 1999 and 2006. Of those, 73 met the definition of having primary refractory disease, ie. progressive disease during first line chemotherapy or within 3 months of completion of the treatment. Those patients achieving complete remission, partial remission and stable disease with symptomatic improvement after two or three cycles of salvage chemotherapy proceeded to stem cell mobilization and autologous transplantation.

Results

From first relapse/progression, the 3-year overall survival was 76% (95% CI: 66%−89%) for the refractory cohort and 91% (95% CI: 84%−98%) for the relapsed cohort (P=0.034); the overall response rate to second-line chemotherapy was 51% and 83% (P<0.0001), respectively. Three-year progression-free survival post-transplant was 49% in refractory patients and 67% in relapsed patients (P=0.21); overall survival was 75% and 91% (P=0.097), respectively.

Conclusions

Using the group with relapsed disease as a reference, we can conclude that the subset of patients with chemosensitive primary refractory Hodgkin’s lymphoma do benefit from autologous stem-cell transplantation.     

Quercetin-mediated Mcl-1 and survivin downregulation restores TRAIL-induced apoptosis in non-Hodgkin's lymphoma B cells

Background

Non-Hodgkin''s B-cell lymphomas account for approximately 70% of B-cell lymphomas. While its incidence is dramatically increasing worldwide, the disease is still associated with high morbidity due to ineffectiveness of conventional therapies, creating an urgent need for novel therapeutic approaches. Unconventional compounds, including polyphenols and the cytokine TRAIL, are being extensively studied for their capacity to restore apoptosis in a large number of tumors, including lymphomas.

Design and Methods

Molecular mechanisms of TRAIL-resistance and reactivation of the apoptotic machinery by quercetin in non-Hodgkin’s lymphoma cell lines were determined by Hoescht, flow cytometry, Western blot, qPCR, by use of siRNA or pharmacological inhibitors of the mitochondrial pathway and by immunoprecipitation followed by post-translational modification analysis.

Results

Results demonstrate that quercetin, a natural flavonoid, restores TRAIL-induced cell death in resistant transformed follicular lymphoma B-cell lines, despite high Bcl-2 expression levels due to the chromosomal translocation t(14;18). Quercetin rescues mitochondrial activation by inducing the proteasomal degradation of Mcl-1 and by inhibiting survivin expression at the mRNA level, irrespective of p53. Restoration of the TRAIL pathway requires Bax and Bak but is independent of enhanced TRAIL DISC formation.

Conclusions

We demonstrate that inactivation of survivin and Mcl-1 expression by quercetin is sufficient to restore TRAIL sensitivity in resistant non–Hodgkin’s lymphoma B cells. Our results suggest, therefore, that combining quercetin with TRAIL treatments may be useful in the treatment of non–Hodgkin’s lymphoma.     

The inducible T-cell co-stimulator molecule is expressed on subsets of T cells and is a new marker of lymphomas of T follicular helper cell-derivation

Background

T follicular helper (T_FH) cells reside in the light zone of germinal centers and are considered the cell of origin of angioimmunoblastic T-cell lymphoma. Recently, CXCL13, PD-1 and SAP were described as useful markers for T_FH cells and angioimmunoblastic T-cell lymphoma but also reported in some peripheral T-cell lymphomas, not otherwise specified.

Design and Methods

In the present study the expression pattern of ICOS protein was investigated by immunohistochemistry-based techniques in routine sections of normal lymphoid tissues and 633 human lymphomas.

Results

Cells strongly positive for ICOS were restricted to the light zone of germinal centers and co-expressed T_FH-associated molecules. In addition, weak to moderate ICOS expression was observed in a small proportion of FOXP3-positive cells. In lymphomas, ICOS expression was confined to angioimmunoblastic T-cell lymphoma (85/86), peripheral T-cell lymphomas of follicular variant (18/18) and a proportion of peripheral T-cell lymphomas, not otherwise specified (24/56) that also expressed other T_FH-associated molecules.

Conclusions

ICOS is a useful molecule for identifying T_FH cells and its restricted expression to angioimmunoblastic T-cell lymphoma and a proportion of peripheral T-cell lymphomas, not otherwise specified (showing a T_FH-like profile) suggests its inclusion in the antibody panel for diagnosing T_FH-derived lymphomas. Our findings provide further evidence that the histological spectrum of T_FH-derived lymphomas is broader than previously assumed.     

A functional dynamic scoring model to elucidate the significance of post-induction interim fluorine-18-fluorodeoxyglucose positron emission tomography findings in patients with Hodgkin��s lymphoma

Background

The findings of interim fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET/CT) predict progression-free survival of patients with Hodgkin’s lymphoma. Historically, the assessment was based on a static all-or-none scoring system. However, the clinical significance of any positivity in interim FDG-PET/CT has not been defined.

Design and Methods

Ninety-six patients with Hodgkin’s lymphoma who underwent interim FDG-PET/CT were evaluated using dynamic and visual scores, employing mediastinal or liver blood pool uptake as a comparator. FDG-PET/CT was prospectively defined as positive if any abnormal F¹⁸FDG uptake was present. In a retrospective analysis dynamic score 0 indicated resolution of all disease sites; score 1 defined a single residual focus; score 2 denoted a reduction in the number of foci; score 3 defined a reduction in intensity with no reduction in number; and score 4 indicated no change in the number and intensity of foci or appearance of new foci.

Results

The dynamic visual score review reduced the number of positive interim studies from 24 to 6 if a score of 2 or less was considered negative, with significantly better specificity (96%) as compared to static visual scores (78%–86%). The 5-year progression-free survival and overall survival rates in patients who had a negative dynamic score were 92% and 97%, respectively; the corresponding figures for patients with positive results were 50% and 67%.

Conclusions

A dynamic visual score may be a better indicator for tailoring therapy than static visual scoring.     

Elevated risk of chronic lymphocytic leukemia and other indolent non-Hodgkin’s lymphomas among relatives of patients with chronic lymphocytic leukemia

Background

Previous studies have shown increased familial risk for chronic lymphocytic leukemia. In the most comprehensive study to date, we evaluated risk of chronic lymphocytic leukemia and lymphoproliferative disorders among first-degree relatives of chronic lymphocytic leukemia cases compared to first-degree relatives of controls.

Design and Methods

Population-based registry data from Sweden were used to evaluate outcomes in 26,947 first-degree relatives of 9,717 chronic lymphocytic leukemia patients (diagnosed 1958–2004) compared with 107,223 first-degree relatives of 38,159 matched controls. Using a marginal survival model, we calculated relative risks (RR) and 95% confidence intervals as measures of familial aggregation.

Results

Compared to relatives of controls, relatives of chronic lymphocytic leukemia patients had an increased risk for chronic lymphocytic leukemia (RR=8.5, 6.1–11.7) and other non-Hodgkin’s lymphomas (NHLs) (RR=1.9, 1.5–2.3). Evaluating NHL subtypes, we found a striking excess of indolent B-cell NHL, specifically lymphoplasmacytic lymphoma/Waldenström macroglobulinemia and hairy cell leukemia. No excesses of aggressive B-cell or T-cell lymphomas were found. There was no statistical excess of Hodgkin’s lymphoma, multiple myeloma, or the precursor condition, monoclonal gammopathy of undetermined significance, among chronic lymphocytic leukemia relatives.

Conclusions

These familial aggregations are striking and provide novel clues to research designed to uncover early pathogenetic mechanisms in chronic lymphocytic leukemia including studies to identify germ line susceptibility genes. However, clinicians should counsel their chronic lymphocytic leukemia patients emphasizing that because the baseline population risks are low, the absolute risk for a first-degree relative to develop chronic lymphocytic leukemia or another indolent lymphoma is low. At this time, an increased medical surveillance of first-degree relatives of chronic lymphocytic leukemia patients has no role outside research studies.     

Dynamic chromosomal rearrangements in Hodgkin��s lymphoma are due to ongoing three-dimensional nuclear remodeling and breakage-bridge-fusion cycles

Background

Hodgkin’s lymphoma is characterized by the presence of mono-nucleated Hodgkin cells and bi- to multi-nucleated Reed-Sternberg cells. We have recently shown telomere dysfunction and aberrant synchronous/asynchronous cell divisions during the transition of Hodgkin cells to Reed-Sternberg cells.¹

Design and Methods

To determine whether overall changes in nuclear architecture affect genomic instability during the transition of Hodgkin cells to Reed-Sternberg cells, we investigated the nuclear organization of chromosomes in these cells.

Results

Three-dimensional fluorescent in situ hybridization revealed irregular nuclear positioning of individual chromosomes in Hodgkin cells and, more so, in Reed-Sternberg cells. We characterized an increasingly unequal distribution of chromosomes as mono-nucleated cells became multi-nucleated cells, some of which also contained chromosome-poor ‘ghost’ cell nuclei. Measurements of nuclear chromosome positions suggested chromosome overlaps in both types of cells. Spectral karyotyping then revealed both aneuploidy and complex chromosomal rearrangements: multiple breakage-bridge-fusion cycles were at the origin of the multiple rearranged chromosomes. This conclusion was challenged by super resolution three-dimensional structured illumination imaging of Hodgkin and Reed-Sternberg nuclei. Three-dimensional super resolution microscopy data documented inter-nuclear DNA bridges in multi-nucleated cells but not in mono-nucleated cells. These bridges consisted of chromatids and chromosomes shared by two Reed-Sternberg nuclei. The complexity of chromosomal rearrangements increased as Hodgkin cells developed into multi-nucleated cells, thus indicating tumor progression and evolution in Hodgkin’s lymphoma, with Reed-Sternberg cells representing the highest complexity in chromosomal rearrangements in this disease.

Conclusions

This is the first study to demonstrate nuclear remodeling and associated genomic instability leading to the generation of Reed-Sternberg cells of Hodgkin’s lymphoma. We defined nuclear remodeling as a key feature of Hodgkin’s lymphoma, highlighting the relevance of nuclear architecture in cancer.     

Low levels of monoclonal small B cells in the bone marrow of patients with diffuse large B-cell lymphoma of activated B-cell type but not of germinal center B-cell type

Background

Multiparameter flow cytometry allows the detection of minor monoclonal B-cell populations. Using this technique combined with morphology, we were struck by the presence of minor populations of small monoclonal B cells in bone marrows of patients with diffuse large B-cell lymphoma in routine diagnostic samples and performed a systematic retrospective study.

Design and Methods

Bone marrows of 165 patients with primary diffuse large B-cell lymphoma without histological evidence of concurrent non-Hodgkin’s lymphoma were studied by routine microscopy of trephines and smears, immunohistochemistry and multiparameter flow cytometry.

Results

Diffuse large B-cell lymphoma infiltration in marrows was documented in 11 of 165 patients. Morphological examination consistently revealed a higher tumor load than evidenced by flow cytometry. Of interest, only 3 of 119 patients with diffuse large B-cell lymphoma not otherwise specified, the largest subtype, showed marrow infiltration. By contrast, flow cytometry revealed a minor monoclonal B-cell population in 24 of 165 patients, none of whom showed diffuse large B-cell lymphoma infiltration by morphology. Of interest, morphological examination revealed the presence of small B cells in the marrows of those patients. Moreover, 11 of 39 (28.2%) of patients with diffuse large B-cell lymphoma not otherwise specified of ABC subtype and only 3 of 80 (3.7%) with the GCB subtype showed these monoclonal small B cells (P=0.0002). In addition 4 of 8 (50%), 4 of 15 (26.7%) and 2 of 3 (66.7%) patients with primary testicular, primary central nervous system and leg-type diffuse large B-cell lymphoma, respectively, showed monoclonal small B cells.

Conclusions

Bone marrow infiltration with diffuse large B-cell lymphoma in patients with diffuse large B-cell lymphoma not otherwise specified is rare at diagnosis. By contrast, a high number of diffuse large B-cell lymphoma not otherwise specified of the ABC subtype but not of GCB subtype is associated with monoclonal small B cells in the marrow. Whether these monoclonal small B cells are precursors of diffuse large B-cell lymphoma of the ABC type or arise in a common background that favors clonal B-cell expansion remains to be demonstrated.     

Reduced intensity conditioning allogeneic stem cell transplantation for Hodgkin’s lymphoma: identification of prognostic factors predicting outcome

Background

The role of reduced intensity conditioning allogeneic stem transplantation (RICalloSCT) in the management of patients with Hodgkin’s lymphoma remains controversial.

Design and Methods

To further define its role we have conducted a retrospective analysis of 285 patients with HL who underwent a RICalloSCT in order to identify prognostic factors that predict outcome. Eighty percent of patients had undergone a prior autologous stem cell transplantation and 25% had refractory disease at transplant.

Results

Non-relapse mortality was associated with chemorefractory disease, poor performance status, age >45 and transplantation before 2002. For patients with no risk factors the 3-year non-relapse mortality rate was 12.5% compared to 46.2% for patients with 2 or more risk factors. The use of an unrelated donor had no adverse effect on the non-relapse mortality. Acute graft versus host disease (aGVHD) grades II–IV developed in 30% and chronic GVHD in 42%. The development of cGVHD was associated with a lower relapse rate. The disease progression rate at one and five years was 41% and 58.7% respectively and was associated with chemorefractory disease and extent of prior therapy. Donor lymphocyte infusions were administered to 64 patients for active disease of whom 32% showed a clinical response. Eight out of 18 patients receiving donor lymphocyte infusions alone had clinical responses. Progression-free and overall survival were both associated with performance status and disease status at transplant. Patients with neither risk factor had a 3-year PFS and overall survival of 42% and 56% respectively compared to 8% and 25% for patients with one or more risk factors. Relapse within six months of a prior autologous transplant was associated with a higher relapse rate and a lower progression-free.

Conclusions

This analysis identifies important clinical parameters that may be useful in predicting the outcome of RICaIICalloSCT in Hodgkin’s lymphoma.     

Subcutaneous injections of low-dose veltuzumab (humanized anti-CD20 antibody) are safe and active in patients with indolent non-Hodgkin's lymphoma

Background

Subcutaneous injections of anti-CD20 antibodies may offer benefits to both patients and the healthcare system for treatment of B-cell malignancies.

Design and Methods

A pilot study was undertaken to evaluate the potential for subcutaneous dosing with 2^nd generation anti-CD20 antibody veltuzumab in patients with CD20⁺ indolent non-Hodgkin’s lymphoma. Patients with previously untreated or relapsed disease received 4 doses of 80, 160, or 320 mg veltuzumab injected subcutaneously every two weeks. Responses were assessed by computed tomography scans, with other evaluations including adverse events, safety laboratories, B-cell blood levels, serum veltuzumab levels, and human anti-veltuzumab antibody (HAHA) titers.

Results

Seventeen patients (14 follicular lymphoma; 13 stage III or IV disease; 5 treatment-naive) completed treatment with only occasional, mild-moderate, transient injection reactions and no other safety issues. Subcutaneous veltuzumab demonstrated a slow release pattern over several days, achieving a mean Cmax of 19, 25 and 63 μg/mL at 80, 160, and 320 mg doses for a total of 4 administrations, respectively. Depletion of circulating B cells occurred after the first injection. The objective response rate (partial responses plus complete responses plus complete responses unconfirmed) was 47% (8/17) with a complete response/complete response unconfirmed rate of 24% (4/17); 4 of 8 objective responses continued for 60 weeks or more. All serum samples evaluated for human anti-veltuzumab antibody were negative.

Conclusions

Subcutaneous injections of low-dose veltuzumab are convenient, well tolerated, and capable of achieving sustained serum levels, B-cell depletion, and durable objective responses in indolent non-Hodgkin’s lymphoma. (Clinicaltrials.gov identifier: {"type":"clinical-trial","attrs":{"text":"NCT00546793","term_id":"NCT00546793"}}NCT00546793)