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The 13th International Conference on Malignant Lymphoma held in Lugano in June 2015 was preceded by a closed workshop (organized in collaboration with the American Association for Cancer Research and the European School of Oncology) with the aim of developing an up-to-date understanding of the biology of follicular lymphoma and the clinical implications of new findings in the field. Discussed topics included the mutational spectrum at diagnosis, the clinical correlates of genetic and epigenetic alterations, the mechanisms of clonal evolution and histological transformation, the cross talk between tumor cells and microenvironment, and the development of novel treatments. This report represents a summary of the workshop., (Copyright © 2017 John Wiley & Sons, Ltd.)

There is limited information concerning the impact of physical activity and obesity on non-Hodgkin lymphoma (NHL) prognosis. We examined the associations between pre-diagnosis physical activity and body mass index (BMI) with survival in 238 diffuse large B-cell (DLBCL) and 175 follicular lymphoma cases, with follow-up from 2000 to 2015. The most physically active DLBCL cases had 41% lower risk of dying in the follow-up period than the least active [Hazard ratio (HR) = 0·59, 95% confidence interval (CI) = 0·36-0·96], while obese follicular lymphoma cases had a 2·5-fold risk of dying (HR = 2·52, 95% CI = 1·27-5·00) compared with cases with normal BMI. NHL-specific survival results were similar., (© 2017 John Wiley & Sons Ltd.)

Primary cutaneous anaplastic large cell lymphoma (PCALCL) is a rare CD30 + lymphoproliferative disorder with excellent outcomes reported despite frequent cutaneous relapses. Limited information exists on the development of systemic lymphoma. The British Columbia Cancer Agency (BCCA) Lymphoid Cancer Database was searched to identify all adults diagnosed with PCALCL from 1993 to 2013. From 2005, the BCCA endorsed radiotherapy (RT) alone for limited stage with data failing to support chemotherapy. Forty-seven patients were identified with a male predominance (n = 31, 66%), median age of 64 years and predominantly limited stage (n = 40, 85%). Median follow-up was 8·4 years. The 5-year time to progression (TTP) was 58% (64% limited versus 29% advanced stage). The 5-year disease-specific survival (DSS) and overall survival was 86% and 75%, respectively. In an as-treated analysis, the 5-year DSS for limited stage patients was similar comparing RT to combined modality treatment or chemotherapy alone but the 5-year TTP favoured RT (82% vs. 33%, P = 0·004). The 5-year cumulative risk of developing systemic lymphoma was 14%. Our results confirm the favourable prognosis of PCALCL despite a high relapse rate. Limited stage patients treated with RT alone have excellent outcomes. There is a small risk of systemic lymphoma in PCALCL., (© 2016 John Wiley & Sons Ltd.)

The addition of rituximab has improved outcomes in diffuse large B-cell lymphoma (DLBCL), however, there remains limited information on the impact of rituximab in those with testicular involvement. All patients with diffuse large cell lymphoma and testicular involvement treated with curative intent were identified in the British Columbia Cancer Agency Lymphoid Cancer Database. In total, 134 patients diagnosed between 1982 and 2015 with diffuse large cell lymphoma involving the testis were identified: 61 received CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone)-like chemotherapy and 73 received CHOP plus rituximab (R-CHOP). A greater proportion of R-CHOP treated patients had higher International Prognostic Index (IPI, P = 0·005). In multivariate analysis, the protective effect of rituximab on progression-free survival (hazard ratio (HR) 0·42, P < 0·001), overall survival (HR 0·39, P < 0·001) and cumulative incidence of progression (HR 0·46, P = 0·014) were independent of the IPI. However, in a competing risk multivariate analysis including central nervous system (CNS) prophylaxis and the CNS-IPI, rituximab was not associated with a decreased risk of CNS relapse. The addition of rituximab has reduced the risk of lymphoma recurrence in testicular DLBCL, presumably through improved eradication of systemic disease. However, CNS relapse risk remains high and further studies evaluating effective prophylactic strategies are needed., (© 2016 John Wiley & Sons Ltd.)

The rituximab extended schedule or retreatment trial (RESORT; E4402) was a phase 3 randomized prospective trial comparing maintenance rituximab (MR) versus a retreatment (RR) dosing strategy in asymptomatic, low tumour burden indolent lymphoma. A planned exploratory sub-study compared the two strategies for small lymphocytic (SLL) and marginal zone lymphomas (MZL). Patients responding to rituximab weekly × 4 were randomized to MR (single dose rituximab every 3 months until treatment failure) or RR (rituximab weekly × 4) at the time of each progression until treatment failure. The primary endpoint was time to treatment failure (TTTF). Patients with SLL (n = 57), MZL (n = 71) and unclassifiable small B-cell lymphoma (n = 3) received induction rituximab. The overall response rate (ORR) was 40% [95% confidence interval (CI) 31-49%; SLL ORR 22·8%; MZL ORR 52·1%]; all 52 responders were randomized. At a median of 4·3 years from randomization, treatment failure occurred in 18/23 RR and 15/29 MR. The median TTTF was 1·4 years for RR and 4·8 years for MR (P = 0·012); median time to first cytotoxic therapy was 6·3 years for RR and not reached for MR (P = 0·0002). Survival did not differ (P = 0·72). In low tumour burden SLL and MZL patients responding to rituximab induction, MR significantly improved TTTF as compared with RR., (© 2016 John Wiley & Sons Ltd.)

We recently defined event-free survival at 24 months (EFS24) as a clinically relevant outcome for patients with DLBCL. Patients who fail EFS24 have very poor overall survival, while those who achieve EFS24 have a subsequent overall survival equivalent to that of the age- and sex-matched general population. Here, we develop and validate a clinical risk calculator (IPI24) for EFS24. Model building was performed on a discovery dataset of 1,348 patients with DLBCL and treated with anthracycline-based immunochemotherapy. A multivariable model containing age, Ann Arbor stage, normalized serum LDH, ALC, ECOG performance status, bulky disease, and sex was identified. The model was then applied to an independent validation dataset of 1,177 DLBCL patients. The IPI24 score estimates the probability of failing to achieve the EFS24 endpoint for an individual patient. The IPI24 model showed superior discriminatory ability (c-statistic = 0.671) in the validation dataset compared to the IPI (c-statistic = 0.649) or the NCCN-IPI (c-statistic = 0.657). After recalibration of the model on the combined dataset, the median predicted probability of failing to achieve EFS24 was 36% (range, 12-88%), and the IPI24 showed an EFS24 gradient in all IPI groups. The IPI24 also identified a significant percentage of patients with high risk disease, with over 20% of patients having a 50% or higher risk of failing to achieve EFS24. The IPI24 provides an individual patient level probability of achieving the clinically relevant EFS24 endpoint. It can be used via electronic apps., (© 2015 Wiley Periodicals, Inc.)

The International Prognostic Score (IPS-7) is the most commonly used risk stratification tool for advanced Hodgkin lymphoma (HL), however recent studies suggest the IPS-7 is less discriminating due to improved outcomes with contemporary therapy. We evaluated the seven variables for IPS-7 recorded at study entry for 854 patients enrolled on Eastern Cooperative Oncology Group 2496 trial. Univariate and multivariate Cox models were used to assess their prognostic ability for freedom from progression (FFP) and overall survival (OS). The IPS-7 remained prognostic however its prognostic range has narrowed. On multivariate analysis, two factors (age, stage) remained significant for FFP and three factors (age, stage, haemoglobin level) for OS. An alternative prognostic index, the IPS-3, was constructed using age, stage and haemoglobin level, which provided four distinct risk groups [FFP (P = 0·0001) and OS (P < 0·0001)]. IPS-3 outperformed the IPS-7 on risk prediction for both FFP and OS by model fit and discrimination criteria. Using reclassification calibration, 18% of IPS-7 low risk patients were re-classified as intermediate risk and 13% of IPS-7 intermediate risk patients as low risk. For patients with advanced HL, the IPS-3 may provide a simpler and more accurate framework for risk assessment in the modern era. Validation of these findings in other large data sets is planned., (© 2015 John Wiley & Sons Ltd.)

Gray zone lymphoma (GZL) with features between classical Hodgkin lymphoma and diffuse large B-cell lymphoma (DLBCL) is a recently recognized entity reported to present primarily with mediastinal disease (MGZL). We examined detailed clinical features, outcomes, and prognostic factors among 112 GZL patients recently treated across 19 North American centers. Forty-three percent of patients presented with MGZL, whereas 57% had non-MGZL (NMGZL). NMGZL patients were older (50 versus 37 years, P = 0.0001); more often had bone marrow involvement (19% versus 0%, P = 0.001); >1 extranodal site (27% versus 8%, P = 0.014); and advanced stage disease (81% versus 13%, P = 0.0001); but they had less bulk (8% versus 44%, P = 0.0001), compared with MGZL patients. Common frontline treatments were cyclophosphamide-doxorubicin-vincristine-prednisone +/- rituximab (CHOP+/-R) 46%, doxorubicin-bleomycin-vinblastine-dacarbazine +/- rituximab (ABVD+/-R) 30%, and dose-adjusted etoposide-doxorubicin-cyclophosphamide-vincristine-prednisone-rituximab (DA-EPOCH-R) 10%. Overall and complete response rates for all patients were 71% and 59%, respectively; 33% had primary refractory disease. At 31-month median follow-up, 2-year progression-free survival (PFS) and overall survival rates were 40% and 88%, respectively. Interestingly, outcomes in MGZL patients seemed similar compared with that of NMGZL patients. On multivariable analyses, performance status and stage were highly prognostic for survival for all patients. Additionally, patients treated with ABVD+/-R had markedly inferior 2-year PFS (22% versus 52%, P = 0.03) compared with DLBCL-directed therapy (CHOP+/-R and DA-EPOCH-R), which persisted on Cox regression (hazard ratio, 1.88; 95% confidence interval, 1.03-3.83; P = 0.04). Furthermore, rituximab was associated with improved PFS on multivariable analyses (hazard ratio, 0.35; 95% confidence interval, 0.18-0.69; P = 0.002). Collectively, GZL is a heterogeneous and likely more common entity and often with nonmediastinal presentation, whereas outcomes seem superior when treated with a rituximab-based, DLBCL-specific regimen., (© 2015 Wiley Periodicals, Inc.)

Patients with early stage diffuse large B-cell lymphoma (DLBCL) receive RCHOP (rituximab cyclophosphamide, doxorubicin, vincristine, prednisone) alone or with involved field radiotherapy (IFRT). Anti-CD20 radioimmunotherapy (RIT) delivers radiation to microscopic sites outside of known disease. This phase II study aimed to achieve a functional complete response (CR) rate of ≥75% to RCHOP and (90) Yttrium-ibritumomab tiuxetan RIT. Patients with stages I/II DLBCL received 4-6 cycles of RCHOP followed by RIT [14·8 MBq/kg (0·4 mCi/kg)]; patients with positron emission tomographypositive sites of disease after RCHOP/RIT received 30 Gy IFRT. Of the 62 patients enrolled; 53 were eligible. 42% (22/53) had stage I/IE; 58% (31/53) stage II/IIE. After RCHOP, 79% (42/53) were in CR/unconfirmed CR. Forty-eight patients proceeded to RIT. One partial responder after RIT received IFRT and achieved a CR. The best response after RCHOP + RIT in all 53 patients was a functional CR rate of 89% (47/53; 95% confidence interval: 77-96%). With a median follow-up of 5·9 years, 7 (13%) patients have progressed and 4 (8%) have died (2 with DLBCL). At 5 years, 78% of patients remain in remission and 94% are alive. Chemoimmunotherapy and RIT is an active regimen for early stage DLBCL patients. Eighty-nine percent of patients achieved functional CR without the requirement of IFRT. This regimen is worthy of further study for early stage DLBCL in a phase III trial., (© 2015 John Wiley & Sons Ltd.)

Splenic marginal zone lymphoma (SMZL) accounts for less than 2% of all non-Hodgkin lymphomas. We identified 107 cases diagnosed with SMZL between 1985 and 2012 from the British Columbia Cancer Agency Centre for Lymphoid Cancer and Lymphoma Pathology Databases. Patient characteristics were: median age 67 years (range 30-88), male 40%, stage IV 98%, splenomegaly 93%, bone marrow involvement 96%, peripheral blood involvement 87%. As initial treatment, 52 underwent splenectomy (10 with chemotherapy), 38 chemotherapy alone (21 chemoimmunotherapy containing rituximab, 1 rituximab alone), two antivirals for hepatitis C, and 15 were only observed. The 10-year overall survival for first-line splenectomy versus chemotherapy was 61% and 42%, respectively [Hazard Ratio (HR) 0·48, 95% confidence interval (CI) 0·26-0·88, P = 0·017]. The 10-year failure-free survival (FFS) after first-line splenectomy vs chemotherapy was 39% and 14%, respectively (HR 0·48, 95% CI 0·28-0·80, P = 0·004). Among the 38 patients who received first-line chemotherapy, FFS was similar between those receiving rituximab (n = 22) and those who did not (n = 16) (HR 0·64, 95% CI 0·31-1·34, P = 0·238). Fifteen patients transformed to aggressive lymphoma with median time to transformation of 3·5 years (range 6 months to 12 years) and the 10-year transformation rate was 18%. In conclusion, splenectomy remains a reasonable treatment for patients with SMZL., (© 2015 John Wiley & Sons Ltd.)

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) and T cell/histiocyte rich large B cell lymphoma (THRLBCL) usually affect middle-aged men, show tumour cells with a B cell phenotype and a low tumour cell content. Whereas the clinical behaviour of NLPHL is indolent, THRLBCL presents with advanced stage disease and an aggressive behaviour. In the present study, array comparative genomic hybridization was performed in seven typical NLPHL, four THRLBCL-like NLPHL variants, six THRLBCL and four diffuse large B cell lymphomas (DLBCL) derived from NLPHL. The number of genomic aberrations was higher in THRLBCL compared with typical and THRLBCL-like variant of NLPHL. Gains of 2p16.1 and losses of 2p11.2 and 9p11.2 were commonly observed in typical and THRLBCL-like variants of NLPHL as well as THRLBCL. Gains of 2p16.1, affecting the REL locus were confirmed in an independent cohort. Expression of the REL protein was observed at similar frequencies in typical and THRLBCL-like variant of NLPHL as well as THRLBCL (33-38%). In conclusion, the present study reveals further similarities between NLPHL and THRLBCL on the genomic level, confirming that these entities are part of a pathobiological spectrum with common molecular features, but varying clinical presentations., (© 2015 John Wiley & Sons Ltd.)

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease with variable therapeutic responses and alternative therapies are needed for patients with unfavourable treatment outcomes after standard treatment with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone). One promising candidate is brentuximab vedotin, an antibody-drug conjugate targeting CD30-expressing cells. However, CD30 (TNFRSF8) expression patterns in DLBCL are not well described thus far. Here, we examined CD30 expression in a population-based cohort of immunocompetent patients from British Columbia with de novo DLBCL using immunohistochemistry. 385 cases of formalin-fixed paraffin-embedded DLBCL in tissue microarrays were evaluated. 95 cases (25%) harboured CD30+ tumour cells. Using a > 0% cut-off, CD30 expression was predictive of superior 5-year progression-free survival within R-CHOP treated germinal centre B-cell-like (GCB) DLBCL (86% vs. 64%, P = 0·020), which was independent of the International Prognostic Index. Epstein-Barr virus (EBV) was identified in 11 (3%) cases, all of which were non-GCB (P = 0·001) and almost exclusively positive for CD30 expression (10/11) (P < 0·001). We conclude CD30 is expressed in a substantial proportion of DLBCL and CD30 immunohistochemistry may be a useful prognostic marker in R-CHOP treated GCB-DLBCL. The significant association of CD30 with EBV-positive non-GCB DLBCL suggests a distinct pathobiology for these cases., (© 2014 John Wiley & Sons Ltd.)

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease and "double-hit" DLBCL, with both MYC and BCL2 translocations has a poor prognosis. In this study, we investigated whether MYC and BCL2 protein expression in tissue would predict survival in DLBCL. The study included 106 cases of de novo DLBCL treated with rituximab and cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) or CHOP-like regimens. The results were validated on an independent cohort of 205 DLBCL patients. Patients with low expression of BCL2 (≤30%) and MYC (≤50%) had the best prognosis, whereas those with high BCL2 (>30%) and MYC (>50%) had the worst outcome. In multivariate analysis, the combination of the BCL2 and MYC was an independent predictor of overall survival (OS) and event-free survival (EFS) (P = 0·015 and P = 0·005, respectively). The risk of death was nine times greater for patients with high BCL2 and MYC compared to those with low expression. High BCL2 and MYC was a strong predictor of poor OS (P < 0·001) and EFS (P = 0·0017) in patients with the germinal centre B-cell (GCB) type, but not in the non-GCB type. In DLBCL, high co-expression of MYC and BCL2 was an independent predictor of poor survival, and could be used to stratify patients for risk-adapted therapies., (© 2014 John Wiley & Sons Ltd.)

There is a lack of contemporary prospective data examining the adriamycin, bleomycin, vinblastine, dacarbazine (ABVD) and Stanford V (SV; doxorubicin, vinblastine, mechlorethamine, vincristine, bleomycin, etoposide, prednisone) regimens in older Hodgkin lymphoma (HL) patients. Forty-four advanced-stage, older HL patients (aged ≥60 years) were treated on the randomized study, E2496. Toxicities were mostly similar between chemotherapy regimens, although 24% of older patients developed bleomycin lung toxicity (BLT), which occurred mainly with ABVD (91%). Further, the BLT-related mortality rate was 18%. The overall treatment-related mortality for older HL patients was 9% vs. 0·3% for patients aged <60 years (P < 0·001). Among older patients, there were no survival differences between ABVD and SV. According to age, outcomes were significantly inferior for older versus younger patients (5-year failure-free survival: 48% vs. 74%, respectively, P = 0·002; 5-year overall survival: 58% and 90%, respectively, P < 0·0001), although time-to-progression (TTP) was not significantly different (5-year TTP: 68% vs. 78%, respectively, P = 0·37). Furthermore, considering progression and death without progression as competing risks, the risk of progression was not different between older and younger HL patients (5 years: 30% and 23%, respectively, P = 0·30); however, the incidence of death without progression was significantly increased for older HL patients (22% vs. 9%, respectively, P < 0·0001). Altogether, the marked HL age-dependent survival differences appeared attributable primarily to non-HL events., (© 2013 Blackwell Publishing Ltd.)

To assess if immunochemotherapy influenced the prognostic value of IPI in elderly diffuse large B-cell lymphoma (DLBCL) patients, we evaluated the performance of the standard International Prognostic Index (IPI) and following modifications: age adjusted (AA)-IPI, revised (R)-IPI, and an elderly IPI with age cut-off 70 years (E-IPI) in patients > 60 years treated with RCHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone). In 267 patients, by IPI/AA-IPI 60% were high-intermediate, 53% high and 12% low risk. With R-IPI, 60% were poor risk and none very good risk. Using E-IPI, 45% were high-intermediate/high risk and 27% low risk. No differences in outcome were seen in the low/low-intermediate groups with IPI/AA-IPI. For E-IPI, failure-free survival (FFS) and overall survival (OS) were significantly different for low/low-intermediate groups. No differences were detected in the four indices with model fit/discrimination measures; however, E-IPI ranked highest. For elderly R-CHOP treated patients, distribution of IPI/AA-IPI skewed toward high/high-intermediate risk with no differences in FFS/OS between low/low-intermediate risk. In contrast, with E-IPI, more are classified as low risk with significant differences in FFS/OS for low-intermediate compared to low risk. The R-IPI does not identify a very good risk group, thus minimizing its utility in this population. The prognostic discrimination provided by the E-IPI for low and low-intermediate elderly DLBCL patients needs validation by other datasets., (© 2010 Blackwell Publishing Ltd.)

Diffuse large B cell lymphoma (DLBCL) is clinically and biologically heterogeneous. In most cases of DLBCL, lymphoma cells co-express vascular endothelial growth factor (VEGF) and its receptors VEGFR1 and VEGFR2, suggesting autocrine in addition to angiogenic effects. We enumerated microvessel density and scored lymphoma cell expression of VEGF, VEGFR1, VEGFR2 and phosphorylated VEGFR2 in 162 de novo DLBCL patients treated with R-CHOP (rituximab, cyclophosphamide, vincristine, doxorubicin and prednisone)-like regimens. VEGFR2 expression correlated with shorter overall survival (OS) independent of International Prognostic Index (IPI) (P = 0.0028). Phosphorylated VEGFR2 (detected in 13% of cases) correlated with shorter progression-free survival (PFS, P = 0.044) and trended toward shorter OS on univariate analysis. VEGFR1 was not predictive of survival on univariate analysis, but it did correlate with better OS on multivariate analysis with VEGF, VEGFR2 and IPI (P = 0.036); in patients with weak VEGFR2, lack of VEGFR1 coexpression was significantly correlated with poor OS independent of IPI (P = 0.01). These results are concordant with our prior finding of an association of VEGFR1 with longer OS in DLBCL treated with chemotherapy alone. We postulate that VEGFR1 may oppose autocrine VEGFR2 signalling in DLBCL by competing for VEGF binding. In contrast to our prior results with chemotherapy alone, microvessel density was not prognostic of PFS or OS with R-CHOP-like therapy.

The tumour suppressor TP53 (previously termed p53) mediates a pathway that is considered to be one of the most important mechanisms in the maintenance of genomic stability. The function of TP53 can be abrogated by genomic deletion, mutation, or deregulation of upstream and downstream participants in the TP53 pathway. While aberrations of TP53 are widely prevalent in non-haematological malignancies (over 60%), they are present in much lower frequency in haematological malignancies (<20%). Nevertheless, in those cases where TP53 function or expression is aberrant, correlation with inferior clinical outcome (such as overall survival and progression or transformation) has generally been strong. In this review, we focus our discussion on the relationship between TP53 and lymphoid malignancies as defined by the World Health Organization. Specifically, we examine the prevalence of TP53 aberrations and their prognostic significance in various types of lymphoid cancer. Next, we discuss the various mechanisms of TP53 inactivation. Finally, we summarize progress in the use of recent therapeutic modalities that target TP53.

Cytogenetic correlations among most types of peripheral T-cell lymphoma (PTCL) have not been very informative to date. This study aimed to identify recurrent chromosomal abnormalities in angioimmunoblastic T-cell lymphoma (AITL), ALK-negative anaplastic large cell lymphoma (ALK-ALCL) and peripheral T-cell lymphoma, unspecified (PTCL-US), and to evaluate their prognostic value. We reviewed the cytogenetic findings of 90 previously-diagnosed cases of PTCL and correlated the cytogenetic findings with the specific histological subtype. The most common abnormalities for AITL were 5q (55%), 21 (41%) and 3q (36%) gains, concurrent trisomies of 5 and 21 (41%), and loss of 6q (23%). In ALK(-) ALCL, gains of 1q (50%) and 3p (30%), and losses of 16pter (50%), 6q13q21 (30%), 15 (30%), 16qter (30%) and 17p13 (30%) were frequent findings. In PTCL-US, frequent gains involved 7q22q31 (33%), 1q (24%), 3p (20%), 5p (20%), and 8q24qter (22%), and losses of 6q22q24 (26%) and 10p13pter (26%). We did not observe any association between specific chromosomal abnormalities and overall survival (OS). However, cases with complex karyotypes, most frequently observed in ALK(-) ALCL and PTCL-US, had a significantly shorter OS. Although, genetic differences were noted in these subtypes, further studies are needed to determine the key pathogenetic events in PTCL.

This study was undertaken to further elucidate the biological mechanisms underlying the frequent event of transformation of follicular lymphoma (FL) to diffuse large B-cell lymphoma (t-FL). The gene expression profiles of 20 paired lymph node biopsies, derived from the same patient pre- and post-transformation, were analysed using the Lymphochip cDNA microarray. TP53 mutation analysis was performed and copy number alterations at the c-REL and CDNK2A examined. Immunohistochemistry was performed on an independent panel of paired transformation paraffin-embedded samples. Transformed follicular lymphoma was predominantly of the germinal centre B-like phenotype both at the mRNA and protein level. Despite this homogeneity, transformation proceeded by at least two pathways. One mechanism was characterised by high proliferation, as assessed by the co-ordinately expressed genes of the proliferation signature. This group was associated with the presence of recurrent oncogenic abnormalities. In the remaining cases, proliferation was not increased and transformation proceeded by alternative routes as yet undetermined. Genes involved in cellular proliferation prevailed amongst those that were significantly increased upon transformation and T cell and follicular dendritic-associated genes predominated amongst those that decreased. t-FL is a germinal centre B (GCB)-like malignancy that evolves by two pathways, one that is similar in proliferation rate to the antecedent FL and the other that has a higher proliferation rate and is characterised by the presence of recognised oncogenic abnormalities.

High dose chemoradiotherapy and haematopoietic stem cell transplantation (SCT) is used as primary therapy for patients diagnosed with Burkitt lymphoma (BL). Forty-three adults presented with sporadic BL in British Columbia between 1987 and 2003. Twenty patients had bone marrow involvement. Sixteen patients did not proceed to SCT because of chemorefractory disease (n = 9) or other reasons (n = 7). Twenty-seven patients proceeded to SCT and had a 3-year event-free survival of 51%. In conclusion, approximately 50% of patients with chemosensitive BL who undergo SCT can be cured; however, a significant number of patients will not proceed to SCT because of early resistance or recurrence.

Forty-four patients with relapsed or refractory aggressive histology non-Hodgkin lymphoma (NHL) (diffuse large B cell, n = 23; peripheral T cell, n = 5; transformed B cell, n = 16) proceeded to allogeneic stem cell transplant (allo-SCT) between 1987 and 2003. Median age at transplant was 40 years (range 19-56 years). At the time of transplant, 35 were chemosensitive and nine were chemorefractory. Thirty-three patients had matched sibling donors and 11 had unrelated donors. Forty-two patients (95%) received radiation-based conditioning regimens. Event-free survival (EFS) and overall survival (OS) at 5 years was 43% [95% confidence interval (CI): 27-58%] and 48% (95% CI: 32-63%) respectively. Treatment-related mortality was 25% at 1 year. Grade III-IV acute graft-versus-host disease (GVHD) was the only significant variable affecting OS and EFS, and had a negative impact. Chronic GVHD did not influence survival. Lymphoma relapse <12 months after initial therapy predicted for increased risk of relapse post-transplant (P = 0.02). Patients with chemorefractory lymphoma were not at increased risk of relapse (P = 0.20) with four of nine patients remaining alive without disease 12-103 months post-transplant. In conclusion, allo-SCT for relapsed or refractory aggressive histology NHL results in long-term EFS and OS of 40-50%. Patients with chemorefractory disease can have a durable remission post-transplant.

The incidence and spectrum of non-Hodgkin lymphoma (NHL) differ between the Chinese and Caucasian populations. Using population-based registries, we studied the pattern of NHL in Chinese migrants to British Columbia (BC). The records of all NHL cases of Chinese descent diagnosed between 1980 and 1997 were retrieved. Age-standardized incidences were calculated by 5-year intervals in terms of age and calendar years and the relative rates were compared between the migrant, Hong Kong and BC populations. The histological distribution of NHL was compared with 4500 consecutive NHL cases diagnosed in the two populations. A total of 211 cases of migrant NHL were identified, with an age-standardized incidence rate of 7.11 per 100 000 per year, compared with the Hong Kong and BC rates of 7.91 [standardized incidence ratio (SIR) = 0.86, P = 0.01] and 11.88 (SIR = 0.56, P < 0.01). The standardized rates of follicular lymphoma remained low, but the incidence of gastric and nasal natural killer/T lymphomas in migrants were lower than expected. Genetic factors appeared to be stronger than environmental factors in governing the overall incidence of NHL in Chinese. However, certain subtypes of lymphoma may show decreased rates in migrants because of environmental factors.

Myeloablative allogeneic bone marrow transplantation (BMT) may be curative in patients with follicular non-Hodgkin's lymphoma, however, the impact of this therapy on long-term survival, disease progression and functional status is less clear. Twenty-nine patients (median age 42 years, range: 20-53) with advanced stage follicular lymphoma proceeded to allogeneic BMT a median of 25 (range: 8-154) months postdiagnosis, between 1985 and 2001, and have been followed for a minimum of 2 years. Eleven of 29 (38%) had refractory disease (n = 5 induction failure, n = 6 resistant relapse). Most (27 of 29, 93%) received total body irradiation-based conditioning; stem cell source was marrow from a related donor (n = 20) or unrelated donor (n = 9). Seventeen of 29 patients (59%) were alive a median of 5 years (range: 2-11) post-BMT with a median Karnofsky Performance Score of 100%. Death occurred because of transplant complications in seven patients (cumulative incidence of non-relapse mortality 24%), and progressive lymphoma in five patients (cumulative incidence of refractory/recurrent lymphoma 23%). The 5-year probability of overall and event-free survival was 58% and 53% respectively. Allogeneic BMT has resulted in long-term disease-free survival for approximately 50% of this cohort of patients with advanced follicular lymphoma and most of them now enjoy robust health.

In order fully to identify secondary chromosomal alterations, such as duplications, additions and marker chromosomes that remained unresolved by G banding, 60 cases of t(14;18)-positive follicular lymphoma (FL) were analysed by multicolour karyotyping techniques [multicolour fluorescence in situ hybridization (MFISH)/multicolour banding for chromosome 1 (MBAND1)]. A total of 165 additional structural chromosomal aberrations were delineated. An increased frequency of chromosomal gains involving X, 1q, 2, 3q27-q29, 5, 6p11-p21, 7, 8, 11, 12, 14q32, 17q, 18 and 21 and deletions of 1p36, 3q28-q29, 6q, 10q22-q24 and 17p11-p13 was revealed by the MFISH/MBAND1 analysis. Balanced translocations other than t(14;18) were uncommon, whereas unbalanced translocations were numerous. Deletion of 1p36 and duplication of 1p33-p35, 1p12-p21 and 1q21-q41 were regularly involved in chromosome 1 alterations, seen in 53% of the cases. A strong correlation was demonstrated between gains of individual chromosomal bands and increased gene expression, including 1q22/MNDA, 6p21/CDKN1A, 12q13-q14/SAS, 17q23/ZNF161, 18q21/BCL2 and Xq13/IL2RG. Unfavourable overall survival was associated with del(1)(p36) and dup(18q). These data support the notion that translocation events are primarily responsible for FL disease initiation, whereas the unbalanced chromosomal gains and losses that mirror the gene expression patterns characterize clonal evolution and disease progression, and thus provide further insights into the biology of FL.

The clinical and pathological features, including karyotype data and BCL2 protein expression pattern, of follicular lymphoma without a t(14;18)(q32;q21) have not been well defined. We have identified and conducted a detailed analysis of 50 cases with follicular lymphoma who lack the t(14;18). Fluorescent in situ hybridization (FISH) analysis was used to exclude cases with a cryptic IGH/BCL2 rearrangement. BCL2 protein expression level was assessed by immunohistochemistry. The karyotypes were assessed for recurrent sites of structural rearrangement, duplications and deletions on a band-by-band basis, and compared with a large cohort of cases with t(14;18). A distinct pattern of chromosomal alterations was identified in the cases without t(14;18). BCL2 protein overexpression was detected in 33% of 49 tested cases. In this minority, the karyotypes frequently showed increased copies of chromosome 18. The majority of cases (67%) did not show BCL2 overexpression and were characterized prominently by the presence of t(3;14)(q27;q32), implying a role for BCL6. Follicular lymphomas that lack a t(14;18) were segregated into two subgroups with distinct cytogenetic, phenotypic and possibly clinical features: one with BCL2 protein overexpression not related to an IGH/BCL2 rearrangement and a second without BCL2 overexpression. Objective identification of BCL2 expression level as well as BCL2 and BCL6 status by cytogenetic or FISH analysis has potential clinical utility and may yield insights into alternative genetic mechanisms associated with B-cell lymphomas with a follicular growth pattern.

Despite several reports of the molecular detection of recurrent lymphoma translocations in reactive lymph nodes (LN), cytogenetic analysis is seldom performed on such cases. We report the clinical and cytogenetic analysis results on 30 reactive LN. Of these, 17 cases yielded either no growth (n = 9) or normal metaphases only (n = 8), and seven of the 17 patients subsequently developed lymphoma. Lymphoma developed in all 10 patients with a clonal karyotype (median of 2.6 months). Three patients (1 HIV-positive) had non-clonal t(3;14) or t(3;22). Their lymphadenopathy resolved spontaneously, and none progressed to lymphoma at 4-6 years of follow-up. Molecular methods detected a small B-cell clone in one case and an oligoclonal B-cell population in the other. Cytogenetic analysis may be useful for interpreting cases of lymphoid hyperplasia. A clonal abnormality is highly predictive of concurrent and/or subsequent lymphoma. A lymphoma-specific but non-clonal abnormality does not necessarily herald the development of subsequent lymphoma., (Copyright 2002 Wiley-Liss, Inc.)

Anaplastic large-cell lymphoma (ALCL) is a heterogeneous process that may have a T-cell, B-cell, or indeterminant (null) phenotype and which may or may not express the anaplastic lymphoma kinase (ALK) oncoprotein. Because the clinical significance of these variants of ALCL is unclear, we evaluated the cases of ALCL-T/null and ALCL-B identified in the Non-Hodgkin's Lymphoma Classification Project. We evaluated 1,378 cases of non-Hodgkin's lymphoma (NHL), and a consensus diagnosis of ALCL-T/null was made in 33 patients (2.4%) with a diagnostic accuracy of 85%. Compared to 96 patients with other forms of peripheral T-cell lymphoma (PTCL), those with ALCL-T/null were significantly younger, less likely to have advanced-stage disease or bone marrow involvement, more likely to have a low International Prognostic Index score, and had a significantly better survival. Among those with ALCL-T/null, there were no significant differences in the clinical features or survival on the basis of ALK expression. A consensus diagnosis of ALCL-B was made in 15 patients (1.1%), and the diagnostic accuracy was 67%. However, compared to 366 patients with other forms of diffuse large B-cell lymphoma (DLBCL), those with ALCL-B were no different with regard to clinical features or survival. We conclude that patients with ALCL-T/null have favorable prognostic features and excellent survival and should be separated from those with other forms of PTCL for prognostic and therapeutic purposes. In contrast, patients with ALCL-B appear to be similar to those with other forms of DLBCL., (Copyright 2001 Wiley-Liss, Inc.)

The clinicopathologic features of anaplastic large cell lymphoma (ALCL) are reviewed. ALCL is a heterogeneous group of tumours, and histologic examination alone is not adequate in providing useful prognostic information. However, using a combination of clinical, phenotypic, and genotypic features, several distinct clinicopathologic entities have been identified. A subset of ALCL as presently defined is characterized by a balanced translocation, t(2;5)(p23;q35), resulting in a novel fusion protein (NPM-ALK) that can be readily detected by immunohistochemical methods using antibodies against the ALK protein. Detection of ALK protein, along with other methods for demonstrating the t(2;5), has assisted in identifying a distinct biologic entity within the heterogeneous group of ALCL with significant prognostic implications. It is important to separate these from cases of ALK-negative ALCL, which have a poorer prognosis, and cases of primary cutaneous ALCL, which have an excellent prognosis., (Copyright 1999 John Wiley & Sons, Ltd.)

Recurrent chromosomal translocations in malignant lymphomas most commonly involve 18q21(bcl-2), 8q24 (c-myc) and 3q27 (bcl-6), with an incidence of 27%, 11% and 6%, respectively. Individual cases concurrently harbouring two of these three rearrangements have been previously reported. This report describes four patients with cytogenetic alterations affecting all three loci, which was confirmed by molecular analysis in one case. Clinically, each patient had aggressive B-cell lymphoma with disseminated disease often involving the central nervous system, poor response to chemotherapy and short survival. Activation of c-myc in association with deregulation of bcl-2, bcl-6 or both confers high-grade disease with a poor prognosis.

Malignant lymphomas (ML) with t(3;14) or variant t(2;3) and t(3;22) have recently been recognized. These translocations have been shown to associate predominantly with B-cell diffuse large cell lymphoma (DLCL) and less frequently with follicular lymphoma (FL). The molecular alterations associated with these translocations involve one of the immunoglobulin gene (Ig) loci and a recently cloned gene, bcl-6 located at 3q27 which codes for a zinc-finger protein that may function as a transcription factor. We have identified by cytogenetic analysis 22 cases of ML with a 3q27/Ig translocation. The pathologic diagnoses of these cases include DLCL, FL, small non-cleaved non-Burkitt lymphoma and chronic lymphocytic leukaemia. Molecular analysis confirmed a bcl-6 rearrangement in 10/12 cases tested. The karyotype in 5/22 cases revealed the t(3;14) or variant in association with another lymphoma-specific translocation, t(14;18) in three cases and t(8;14) in two cases. ML with dual translocations that implicate Ig genes in the deregulation of proto-oncogenes are being increasingly recognized and may represent distinct subtypes or 'hybrid' forms of malignant lymphoma.

To determine the frequency and clinical significance of acquired abnormalities of chromosome 3 at q21 and q25-26 in haematological malignancy, we reviewed the haematological and cytogenetic features of 24 patients with a 3q rearrangement identified amongst 1200 cases with clonal cytogenetic abnormalities detected at our institutions during a 12-year period. Thirteen patients presented with de novo acute myeloid leukaemia (AML), 10 with myelodysplasia (MDS) and one in blast phase of chronic myelogenous leukaemia. Twenty patients (83%) had megakaryocytic dysplasia and 14 (58%) had normal or increased numbers of megakaryocytes, but only four patients (16%) had absolute thrombocytosis > 500 x 10(9)/l (three with AML, one with MDS transforming to AML). A review of 205 cases of AML investigated in our institutions between 1985 and 1990 for whom cytogenetic results were obtained revealed that a platelet count > 500 x 10(9)/l at presentation was highly suggestive of an underlying 3q abnormality. A limited review of the literature on this subject confirmed that 15-20% of patients with a 3q abnormality will have thrombocytosis. The response of these patients to conventional antileukaemic therapy is uniformly poor, despite haematological and clinical differences between the subtypes of 3q rearrangements.