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.     

Cytotoxic molecule-positive classical Hodgkin's lymphoma: a clinicopathological comparison with cytotoxic molecule-positive peripheral T-cell lymphoma of not otherwise specified type

Background

Classical Hodgkin’s lymphoma is characterized by Hodgkin and Reed Sternberg cells, which are of B-cell origin in many cases. We recently highlighted the adverse prognostic significance of cytotoxic molecule expression in patients with classical Hodgkin’s lymphoma. However, the clinical characteristics of cytotoxic molecule-positive classical Hodgkin’s lymphoma remain controversial.

Design and Methods

We investigated the clinicopathological profiles of 32 patients with cytotoxic molecule-positive Hodgkin’s lymphoma, comprising 23 with nodular sclerosis and 9 with mixed cellularity, and compared these profiles with those of 55 patients with cytotoxic molecule-positive nodal peripheral T-cell lymphoma, not otherwise specified and 439 patients with cytotoxic molecule-negative Hodgkin’s lymphoma.

Results

The patients with cytotoxic molecule-positive Hodgkin’s lymphoma consisted of 20 men and 12 women with a median age of 50 years (range, 19 to 81). All these patients had lymphadenopathy at presentation, and 14 showed mediastinal involvement. Physical findings included hepatomegaly and splenomegaly in six patients each. Four patients had a bulky mass, and nine showed stage IV disease. The tumor cells of patients with cytotoxic molecule-positive Hodgkin’s lymphoma had a prototypic immunophenotype of CD15⁺ CD30⁺ CD45RO⁻ fascin⁺, with positivity for Epstein-Barr virus in 39% of cases. All patients were negative for Pax5. In comparison with patients with cytotoxic molecule-positive nodal peripheral T-cell lymphomas, not otherwise specified, patients with cytotoxic-positive Hodgkin’s lymphoma had relatively mild clinical symptoms, similar to those of patients with cytotoxic molecule-negative Hodgkin’s lymphoma. Regarding prognosis, the survival of patients with cytotoxic molecule-positive Hodgkin’s lymphoma was worse than that of patients with cytotoxic molecule-negative Hodgkin’s lymphoma (P=0.0003) but better than that of patients with cytotoxic molecule-positive peripheral T-cell lymphomas, not otherwise specified (P=0.002).

Conclusions

Cytotoxic molecule-positive Hodgkin’s lymphoma is characterized by an unfavorable prognosis, even if its clinicopathological features are within the boundaries of classical Hodgkin’s lymphoma. More effective chemotherapy for cytotoxic molecule-positive Hodgkin’s lymphoma is clearly required.     

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.     

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.     

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.     

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.     

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.     

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.     

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.     

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.     

Clinical, pathological and genetic features of primary mediastinal large B-cell lymphomas and mediastinal gray zone lymphomas in children

Background

Primary mediastinal large B-cell lymphoma is a rare lymphoma accounting for no more than 3% of all B-cell lymphomas in children and adolescents. However, patients in this young age group with this lymphoma have the shortest event-free survival of patients with any B-cell lymphoma under current standard chemotherapy protocols. Lymphomas with features intermediate between primary mediastinal large B-cell lymphoma and classical Hodgkin’s lymphoma (mediastinal gray zone lymphomas) have been acknowledged in the latest World Health Organization classification. Recent studies suggest that mediastinal gray zone lymphomas have an aggressive clinical course whereas patients, at least adult ones, with primary mediastinal large B-cell lymphoma might respond very well to chemotherapy in combination with anti-CD20 antibody.

Design and Methods

We aimed to evaluate whether biological differences or so far unrecognized admixed mediastinal gray zone lymphomas might explain the relatively poor outcome of pediatric patients with apparent primary mediastinal large B-cell lymphoma. We, therefore, performed a retrospective histopathological, immunohistochemical and interphase cytogenetic analysis of 52 pediatric lymphomas.

Results

The childhood primary mediastinal large B-cell lymphomas (n=44) showed a similar pattern of histology, immunophenotype and gains at 9p (59%) and 2p (41%) as adult cases, as determined from published data. We identified only four so far unrecognized cases of mediastinal gray zone lymphoma among 52 lymphomas registered in previous trials.

Conclusions

Mediastinal gray zone lymphoma is very rare in children and adolescents. It does, therefore, seem unlikely that these lymphomas account for the unsatisfactory clinical results with current therapy protocols in pediatric patients. These data have major implications for the design of future treatment protocols for mediastinal lymphomas in children and adolescents.     

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.     

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.     

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.     

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.     

Pediatric follicular lymphoma �C a clinico-pathological study of a population-based series of patients treated within the Non-Hodgkin��s Lymphoma - Berlin-Frankfurt-M��nster (NHL-BFM) multicenter trials

Background

Pediatric follicular lymphoma has recently been recognized as a novel variant of follicular lymphoma in the World Health Organization classification of lymphomas. Given the rarity of the disease, histopathological and genetic data on this type of lymphoma are still scarce.

Design and Methods

We analyzed 25 cases of pediatric follicular lymphoma (patients aged ≤18 years) by morphology, immunohistochemistry and interphase fluorescence in situ hybridization. All patients analyzed were treated within Non-Hodgkin’s Lymphoma - Berlin-Frankfurt-Münster (NHL-BFM) multicenter trials, and the cohort was representative of the German population.

Results

The genetic hallmark of adult follicular lymphoma, t(14;18)(q32;q21), was not detectable in any of the pediatric cases, although BCL2 protein was expressed in 55% of the latter cases. No correlation was found between BCL2 protein expression and outcome. Chromosomal breaks in the immunoglobulin heavy chain gene (IGH) and the BCL6 locus were detected in 5 of 17 and 1 of 18 cases, respectively. Patients with pediatric follicular lymphoma had long event-free survival and, in contrast to adult follicular lymphoma, the clinical course was not dominated by relapses. A simultaneous diffuse large B-cell lymphoma was frequently detected at initial diagnosis in children but did not indicate an aggressive clinical course.

Conclusions

Our data suggest that pediatric follicular lymphoma is a disease that differs from its adult counterpart both genetically and clinically.