Poor outcome for children and adolescents with progressive disease or relapse of lymphoblastic lymphoma: a report from the berlin-frankfurt-muenster group

Disseminated lymphoblastic lymphoma in children and adolescents: results of the COG A5971 trial: a report from the Children's Oncology Group

The Children's Oncology Group's A5971 trial examined central nervous system (CNS) prophylaxis and early intensification in paediatric patients diagnosed with CNS-negative Stage III and IV lymphoblastic lymphoma. Using a 2 × 2 factorial design, the study randomized patients to Children's Cancer Group (CCG) modified Berlin-Frankfurt-Muenster (BFM) acute lymphoblastic leukaemia (ALL) regimen with intensified intrathecal (IT) methotrexate (MTX) (Arm A1) or an adapted non-Hodgkin lymphoma/BFM-95 therapy with high dose MTX in interim maintenance but no IT-MTX in maintenance (Arm B1). Each cohort was randomized ± intensification (cyclophosphamide/anthracycline) (Arms A2/B2). For the 254 randomized patients, there was no difference in 5-year event-free survival (EFS) for the four arms: Arm A1, 80% [95% confidence interval (CI) 67-89%] and Arm A2, 81% (95% CI 69-89%); Arm B1, 80% (95% CI 68-88%) and Arm B2, 84% (95% CI 72-91%). The cumulative incidence of CNS relapse was 1·2%. Age <10 years and institutional imaging response at 2 weeks was associated with improved outcomes (P < 0·001 and P = 0·014 for overall survival). CNS positive patients (n = 12) did poorly [5-year EFS of 63% (95% CI 29-85%)]. For CNS-negative patients, there was no difference in outcome based on CNS prophylaxis (IT-MTX versus HD-MTX) or with intensification.

Adult lymphoblastic lymphoma

Adult lymphoblastic lymphoma (LBL) is an aggressive form of non-Hodgkin lymphoma occurring in predominantly adolescent and young adult men. Lymphoblastic lymphoma is rare, accounting for 1% to 2% of all non-Hodgkin lymphomas and is of T-cell phenotype in 90% of cases. Lymphoblastic lymphoma is morphologically indistinct from acute lymphoblastic leukemia (ALL). Both express their lineage-specific markers as well as terminal deoxynucleotidyl transferase. The differences are often made on clinical grounds. Lymphoblastic lymphoma is characterized by a predominantly nodal distribution of disease, often with a large mediastinal mass. Patients with less than 25% bone marrow involvement have typically been categorized as LBL rather than ALL, although this has not been applied consistently in the literature. Gene expression studies have identified differences in gene expression, with LBL expressing higher levels of genes associated with cytoskeleton, adhesion, angiogenesis, and chemotaxis than ALL. Although LBL and ALL can be distinct clinically, chemotherapy strategies are often very similar. Acute lymphoblastic leukemia regimens, which incorporate intensive multidrug induction, consolidation, delayed intensification, and maintenance, have been shown to be superior to standard lymphoma regimens. As central nervous system (CNS) relapse is common, CNS prophylaxis with high-dose chemotherapy and intrathecal therapy is also standard. The prophylactic use of CNS irradiation has declined with the introduction of chemotherapy regimens incorporating high doses of CNS-penetrating drugs such as cytarabine and methotrexate. The use of consolidative radiation to the mediastinum remains uncertain. High-dose chemotherapy followed by autologous or allogeneic transplantation as consolidation for patients in CR1 is controversial with modern intensive chemotherapy regimens, although transplantation has a proven role in the relapse setting.

High levels of bcl-2 protein expression do not correlate with genetic abnormalities but predict worse prognosis in patients with lymphoblastic lymphoma

We aimed to investigate bcl-2, bcl-6, and c-myc rearrangements in patients with lymphoblastic lymphoma (LBL), especially focus on the correlation of protein expression with genetic abnormalities. Moreover, their prognostic significance was further analyzed in LBL. Protein expression and genetic abnormalities of bcl-2, bcl-6, and c-myc were investigated in microarrayed tumors from 33 cases of T cell LBL and eight cases of B cell lineage. Immunohistochemical (IHC) staining was performed to evaluate protein expression, including bcl-2, bcl-6, c-myc, TdT, CD1α, CD34, Ki-67, PAX-5, CD2, CD3, CD4, CD8, and CD20. Genetic abnormalities of bcl-2, bcl-6, and c-myc were detected by dual color fluorescence in situ hybridization (FISH). Bcl-2 protein was positive in 51.2 % (21/41) of the patients, bcl-6 protein in 7.3 % (three out of 41), and c-myc protein in 78.0 % (32/41). Bcl-2 breakpoint was found in two cases by FISH analysis. There was no evidence of bcl-6 or c-myc rearrangement in patients with LBL. However, both gene gain and loss events occurred in bcl-2, bcl-6, and c-myc. A univariate analysis showed that stage III or IV, elevated lactate dehydrogenase (LDH), and positivity for bcl-2 protein were associated with shorter survival (p<0.05). Enhanced protein expression and detectable genetic abnormalities of bcl-2, bcl-6, and c-myc were observed in patients with LBL. No statistical correlation was found between IHC results and cytogenetic findings. Stage III or IV, elevated LDH, and positivity for bcl-2 protein were identified as adverse prognostic factors. The patients with more adverse factors would have increasingly worse prognosis.

NK/T-cell lymphomas in children

In children, T and NK-cell lymphomas are uncommon in Western Countries. While there has been significant experience treating T-cell lymphoblastic lymphoma (T-LBL) and anaplastic large cell lymphoma (ALCL), other subtypes are very rarely encountered and there are no standard approaches to their management. There are many challenges in defining optimal therapy for many of these diseases but recent progress in elucidating their biology has led to new molecular insights and identified interesting targets for novel drug discovery. In this review, we discuss these disorders in children, how they are approached therapeutically and what lies on the horizon with respect to novel treatment approaches.

Incidence and prognostic relevance of genetic variations in T-cell lymphoblastic lymphoma in childhood and adolescence

Probability of event-free survival (pEFS) in pediatric T-cell lymphoblastic lymphoma is about 80%, whereas survival in relapsed patients is very poor. No stratification criteria have been established so far. Recently, activating NOTCH1 mutations were reported to be associated with favorable prognosis, and loss of heterozygosity at chromosome 6q (LOH6q) was reported to be associated with increased relapse risk. The current project was intended to evaluate the prognostic effect of these markers. Mutations in hot spots of NOTCH1 and FBXW7 were analyzed in 116 patients. Concerning LOH6q status, 118 patients were investigated, using microsatellite marker analysis, in addition to an earlier reported cohort of 99 available patients. Ninety-two cases were evaluable for both analyses. All patients were treated with T-cell lymphoblastic lymphoma-Berlin-Frankfurt-Münster group (BFM)-type treatment. LOH6q was observed in 12% of patients (25/217) and associated with unfavorable prognosis (pEFS 27% ± 9% vs 86% ± 3%; P < .0001). In 60% (70/116) of the patients, NOTCH1 mutations were detected and associated with favorable prognosis (pEFS 84% ± 5% vs 66% ± 7%; P = .021). Interestingly, NOTCH1 mutations were rarely observed in patients with LOH in 6q16. Both prognostic markers will be used as stratification criteria in coming Non-Hodgkin Lymphoma-BFM trials.

The immunophenotype of T-lymphoblastic lymphoma in children and adolescents: a Children's Oncology Group report

T-lymphoblastic leukaemia (T-ALL) and T-lymphoblastic lymphoma (T-LBL) are neoplasms derived from immature lymphoid cells of T-cell lineage. These neoplasms are biologically similar, but significant differences may exist between the two given their clinical differences. Although ample data regarding the immunophenotypic characterization T-ALL are available, there is a paucity of such data in children and adolescents with T-LBL. We used flow cytometry and/or immunohistochemistry to characterize the immunophenotypic profile of 180 children and adolescents with newly diagnosed T-LBL enrolled in the Children's Oncology Group 5971 study. Multiple T-cell, B-cell, myeloid, and other markers were evaluated. We identified diagnostically useful immunophenotypic features of T-LBL as well as distinct immunophenotypic subgroups, although none of these was statistically related to event-free or overall survival in this retrospective analysis. Further studies of biologically and immunophenotypically distinct subgroups of T-LBL, such as the early T-cell precursor phenotype, are warranted.

Pediatric T- and NK-cell lymphomas: new biologic insights and treatment strategies

T- and natural killer (NK)-cell lymphomas are challenging childhood neoplasms. These cancers have varying presentations, vast molecular heterogeneity, and several are quite unusual in the West, creating diagnostic challenges. Over 20 distinct T- and NK-cell neoplasms are recognized by the 2008 World Health Organization classification, demonstrating the diversity and potential complexity of these cases. In pediatric populations, selection of optimal therapy poses an additional quandary, as most of these malignancies have not been studied in large randomized clinical trials. Despite their rarity, exciting molecular discoveries are yielding insights into these clinicopathologic entities, improving the accuracy of our diagnoses of these cancers, and expanding our ability to effectively treat them, including the use of new targeted therapies. Here, we summarize this fascinating group of lymphomas, with particular attention to the three most common subtypes: T-lymphoblastic lymphoma, anaplastic large cell lymphoma, and peripheral T-cell lymphoma-not otherwise specified. We highlight recent findings regarding their molecular etiologies, new biologic markers, and cutting-edge therapeutic strategies applied to this intriguing class of neoplasms.

Double-delayed intensification paediatric protocol without radiotherapy is an efficient treatment in adult lymphoblastic lymphoma

Lymphoblastic lymphoma (LBL) is a rare disease associated with favourable prognosis in childhood but with poor prognosis in adults when treated with conventional non-Hodgkin lymphoma regimens. Improvements in long-term outcome have been made since the use of acute lymphoblastic leukaemia (ALL) regimens. We report here the feasibility of a double-delayed intensification paediatric protocol in 12 adult LBL patients. There were no relapses and no deaths, with a median follow-up of 4.7 years. Using the same protocol, overall survival was significantly longer in LBL patients versus ALL patients (100% vs 75%, p = 0.05). Overall tolerance was acceptable and better in ALL patients. We have shown the feasibility and the good results of using this paediatric protocol in LBL.

Relapsed or refractory anaplastic large-cell lymphoma in children and adolescents after Berlin-Frankfurt-Muenster (BFM)-type first-line therapy: a BFM-group study

PURPOSE

To evaluate risk factors for outcome in children and adolescents with relapse of anaplastic large-cell lymphoma (ALCL) after comparable first-line therapy.

PATIENTS AND METHODS

We analyzed a population-based cohort of 74 children with relapsed ALCL after Berlin-Frankfurt-Muenster-type first-line therapy between April 1990 and December 2003. The recommended salvage strategy was reinduction chemotherapy followed by autologous hematopoietic stem-cell transplantation (SCT).

RESULTS

With a median follow-up time of 8.4 years (range, 4.5 to 16.4 years), the 5-year overall survival (OS) rate after first relapse was 57% ± 6%. Survival correlated with time of relapse and clinically advanced dissemination. Five-year OS of 16 patients who experienced progression during first-line therapy was 25% ± 11% compared with 66% ± 6% for 58 patients with a later relapse (P = .002). Five-year OS of 11 patients with bone marrow or CNS involvement was 27% ± 13% compared with 62% ± 6% for 63 patients without involvement (P = .001). Five-year event-free survival (EFS) and OS of 39 children who received the recommended autologous SCT were 59% ± 8% and 77% ± 7%, respectively. EFS after autologous SCT was significantly associated with time to relapse (progression: n = 3; EFS, 0; later relapse: n = 36; EFS, 64% ± 8%; P = .014) and CD3 expression (CD3 negative: n = 25; EFS, 72% ± 9%; CD3 positive: n = 11; EFS, 18% ± 12%; P < .001), but not with site of relapse, conditioning regimen, or graft manipulation. No relapses occurred among 10 patients with relapsed CD3-positive ALCL treated with allogeneic SCT.

CONCLUSION

Reinduction chemotherapy followed by autologous SCT proved feasible and efficacious for patients with a first relapse of CD3-negative ALCL after first-line therapy. Patients with progression during first-line therapy or relapsed CD3-positive ALCL may benefit from allogeneic SCT.

High-risk pediatric acute lymphoblastic leukemia: to transplant or not to transplant?

Because survival with both chemotherapy and allogeneic hematopoietic stem cell transplantation (HSCT) approaches to high-risk pediatric acute lymphoblastic leukemia (ALL) generally improves through the years, regular comparisons of outcomes with either approach for a given indication are needed to decide when HSCT is indicated. Improvements in risk classification are allowing clinicians to identify patients at high risk for relapse early in their course of therapy. Whether patients defined as high risk by new methods will benefit from HSCT requires careful testing. Standardization and improvement of transplant approaches has led to equivalent survival outcomes with matched sibling and well-matched unrelated donors; however, survival using mismatched and haploidentical donors is generally worse. Trials comparing chemotherapy and HSCT must obtain sufficient data about therapy and stratify the analysis to assess the outcomes of best-chemotherapy with best-HSCT approaches.

Over-expressed Fas improves the apoptosis of malignant T-cells in vitro and vivo

Fas play a critical role in T-cell apoptosis by functioning as a major cell-surface death receptor. To explore a potential method that can improve the sensitivity to Fas-mediated apoptosis in malignant precursor T-cells. Fas gene was stable transfected into Jurkat cells to establish a new cell line named Jurkat-Fas with over-expressed Fas. RT-PCR, real-time RT-PCR, flow cytometry, and confocal microscopy assay were performed to detect the Fas level of mRNA and protein in the two cell lines. The sensitivities to Fas-mediated apoptosis of the two cell lines were evaluated by flow cytometry with Alexa Fluor 488 annexin V/PI staining in vitro. Tumor xenograft models were prepared with Jurkat and Jurkat-Fas cells for in vivo study. Fas mRNA and protein levels in Jurkat-Fas cell line were higher than that in Jurkat cell line. Compared to Jurkat cells, apoptosis rates of Jurkat-Fas cells were remarkably higher in vitro, and the tumor growth of Jurkat-Fas cells in nude mice was significantly inhibited in vivo. Stable over-expression of extrinsic Fas gene can significantly ameliorate the sensitivity to Fas-mediated apoptosis in human malignant T-cell, which indicates a novel strategy to improve therapeutic effects on precursor T-cell malignancy.

Stem cell transplantation in childhood non-Hodgkin's lymphomas

Despite the high cure rates achieved with intensified primary therapies for childhood non-Hodgkin's lymphomas (NHL), the prognosis for children with relapsed or refractory disease is poor. Optimal treatment for this group remains a challenge. Dose intensification followed by stem cell transplantation has been used in these circumstances and may provide a curative treatment option for these patients, but the number of children treated using this approach is relatively small and its effectiveness has been difficult to judge. Moreover, the limited experience is insufficient to define the patient most likely to benefit from transplantation. Likewise, the selection of autologous or allogeneic transplantation and the optimal conditioning regimen are debated. We summarize the current experience for stem cell transplantation in childhood NHL and offer our recommendations.

Successful treatment of multiply relapsed lymphoma with rituximab as a single agent

The treatment of non-Hodgkin lymphoma (NHL) is an example of the successful therapy of cancer in children; the cure rate overall at approximately 80%. Unfortunately, relapsed NHL has a dismal prognosis, and the customary treatment is highly toxic chemotherapy followed by hematopoietic stem cell transplantation (HSCT). A child with relapsed T-cell rich B-NHL was treated with rituximab alone. This was delivered in eight doses after the recurrence of disease after high-dose chemotherapy and allogenic HSCT that was undertaken for the first relapse. Eight years after the last dose of rituximab he remains in complete remission.

Autologous peripheral blood stem cell transplantation in children with refractory or relapsed lymphoma: results of Children's Oncology Group study A5962

This prospective study was designed to determine the safety and efficacy of cyclophosphamide, BCNU, and etoposide (CBV) conditioning and autologous peripheral blood stem cell transplant (PBSCT) in children with relapsed or refractory Hodgkin and non-Hodgkin lymphoma (HL and NHL). Patients achieving complete remission (CR) or partial remission (PR) after 2 to 4 courses of reinduction underwent a granulocyte-colony stimulating factor (G-CSF) mobilized PBSC apheresis with a target collection dose of 5 × 10⁶ CD34(+)/kg. Those eligible to proceed received autologous PBSCT after CBV (7200 mg/m², 450-300 mg/m², 2400 mg/m²). Forty-three of 69 patients (30/39 HL, 13/30 NHL) achieved a CR/PR after reinduction. Thirty-eight patients (28 HL, 10 NHL) underwent PBSCT. All initial 6 patients who received BCNU at 450 mg/m² experienced grade III or IV pulmonary toxicity compared to none of the subsequent 32 receiving 300 mg/m² (P < .0001). The probability of overall survival (OS) at 3 years for all patients is 51% and for transplanted patients is 64%. The 3-year event-free survival (EFS) is 38% (45% for HL; 30% NHL). The 3-year EFS in transplanted patients is 66% (65% HL; 70% NHL). Initial duration of remission of ≥12 versus <12 months was associated with a significant increase in OS (3 years OS 70% versus 34%) (P = .003). BCNU at 300 mg/m(2) in a CBV regimen prior to PBSCT is well tolerated in relapsed or refractory pediatric lymphoma patients. A short duration (<12 months) of initial remission is associated with a poorer prognosis. Last, a high percentage of patients achieving a CR/PR after reinduction therapy can be salvaged with CBV and autologlous PBSCT.

Paediatric lymphoblastic T-cell leukaemia and lymphoma: one or two diseases?

There is ongoing discussion on whether paediatric acute T-cell lymphoblastic leukaemia (T-ALL) and paediatric lymphoblastic T-cell lymphoma (T-LBL) are two distinct entities or whether they represent two variant manifestations of one and the same disease and the distinction is arbitrary. Both show overlapping clinical, morphological and immunophenotypic features. Many clinical trials use the amount of blast infiltration of the bone marrow as the sole criterion to distinguish between T-ALL and T-LBL. The current World Health Organization classification designates both malignancies as T lymphoblastic leukaemia/lymphoma. However, subtle immunophenotypic, molecular and cytogenetic differences suggest that T-ALL and T-LBL might be biologically different in certain aspects. The current review summarizes and discusses the recent advances and understanding of the molecular profile of paediatric T-ALL and T-LBL.