Long-term results of AIEOP LNH-92 protocol for the treatment of pediatric lymphoblastic lymphoma: a report of the Italian Association of Pediatric Hematology and Oncology

Diagnosis and management of lymphoblastic lymphoma in children, adolescents and young adults

Lymphoblastic lymphoma (LBL) is the second most common type of non-Hodgkin Lymphoma (NHL) in children, adolescents, and young adults (CAYA), accounting for 25-35% of all cases. T-lymphoblastic lymphoma (T-LBL) comprises 70-80% of cases, while precursor B-lymphoblastic lymphoma (pB-LBL) makes up the remaining 20-25% of cases. Event-free and overall survival (EFS and OS) for paediatric LBL patients both exceed 80% with current therapies. Treatment regimens, especially in T-LBL with large mediastinal tumours, are complex with significant toxicity and long-term complications. Though prognosis overall is good for T-LBL and pB-LBL with upfront therapy, outcomes for patients with relapsed or refractory (r/r) disease remain dismal. Here, we review new understanding about the pathogenesis and biology of LBL, recent clinical results and future directions for therapy, and remaining obstacles to improve outcomes while reducing toxicity.

Observation of Alectinib‐ and Crizotinib‐ included chemotherapy in children with ALK ‐positive anaplastic large cell lymphoma: A single institutional experience

Approximately one-third children with anaplastic large cell lymphoma (ALCL) relapse after completion of chemotherapy, particularly for those high-risk patients. The introduction of novel therapeutic modalities is much needed for these sub-group patients. Two groups (n = 3, n = 4) of ALCL patients were treated with crizotinib- and alectinib-included ALCL-99 therapy, respectively, achieving complete remission rates of 66.7% and 100%. Two patients of crizotinib group relapsed, while none relapsed among the alectinib-treated patients. Adding alectinib instead of crizotinib sufficiently suppressed and maintained the deep NPM-ALK molecular response. ALK inhibitors were well tolerated with only grade 1 adverse events in both groups. Though a relatively small case number, this study raised the possibility that alectinib-included therapeutic regimens may benefit the early response, in-depth molecular remission, and persistent remission to some extent. Further studies are warranted to validate our preliminary findings.

Oncogenetic landscape of T-cell lymphoblastic lymphomas compared to T-cell acute lymphoblastic leukemia

In the latest 2016 World Health Organization classification of hematological malignancies, T-cell lymphoblastic lymphoma (T-LBL) and lymphoblastic leukemia (T-ALL) are grouped together into one entity called T-cell lymphoblastic leukemia/lymphoma (T-LBLL). However, the question of whether these entities represent one or two diseases remains. Multiple studies on driver alterations in T-ALL have led to a better understanding of the disease while, so far, little data on genetic profiles in T-LBL is available. We sought to define recurrent genetic alterations in T-LBL and provide a comprehensive comparison with T-ALL. Targeted whole-exome next-generation sequencing of 105 genes, multiplex ligation-dependent probe amplification, and quantitative PCR allowed comprehensive genotype assessment in 818, consecutive, unselected, newly diagnosed patients (342 T-LBL vs. 476 T-ALL). The median age at diagnosis was similar in T-LBL and T-ALL (17 vs. 15 years old, respectively; p = 0.2). Although we found commonly altered signaling pathways and co-occurring mutations, we identified recurrent dissimilarities in actionable gene alterations in T-LBL as compared to T-ALL. HOX abnormalities (TLX1 and TLX3 overexpression) were more frequent in T-ALL (5% of T-LBL vs 13% of T-ALL had TLX1 overexpression; p = 0.04 and 6% of T-LBL vs 17% of T-ALL had TLX3 overexpression; p = 0.006). The PI3K signaling pathway was significantly more frequently altered in T-LBL as compared to T-ALL (33% vs 19%; p < 0.001), especially through PIK3CA alterations (9% vs 2%; p < 0.001) with PIK3CA^H1047 as the most common hotspot. Similarly, T-LBL genotypes were significantly enriched in alterations in genes coding for the EZH2 epigenetic regulator and in TP53 mutations (respectively, 13% vs 8%; p = 0.016 and 7% vs 2%; p < 0.001). This genetic landscape of T-LBLL identifies differential involvement of recurrent alterations in T-LBL as compared to T-ALL, thus contributing to better understanding and management of this rare disease.

Ruxolitinib as a Novel Therapeutic Option for Poor Prognosis T-LBL Pediatric Patients

Simple Summary

Current treatment protocols for pediatric patients with T-Lymphoblastic lymphoma (T-LBL) allow the achievement of a complete remission in around 85% of T-LBL pediatric patients; however the overall survival rate of second-line treatments for patients with progressive disease or relapse is around 14%. Thus, the major issues to be addressed are the identification of a valuable predictor marker to foresee the disease risk and new therapeutic targets to improve relapsed/resistant patients’ outcome. We identified JAK2 Y1007-1008 as a potential prognosis marker as well as a therapeutic target for patients with progressive disease or relapse and suggest that its inhibition by ruxolitinib, a JAK1/2 FDA approved inhibitor, could represent a novel therapeutic approach to overcome therapy resistance and meliorate the outcome of pediatric T-LBL patients.

Abstract

Lymphoblastic lymphoma (LBL) is the second most common type of non-Hodgkin lymphoma in childhood, mainly of T cell origin (T-LBL). Although current treatment protocols allow a complete remission in 85% of cases, the second-line treatment overall survival for patients with progressive or relapsed disease is around 14%, making this the major issue to be confronted. Thus, we performed a Reverse Phase Protein Array study in a cohort of 22 T-LBL patients to find reliable disease risk marker(s) and new therapeutic targets to improve pediatric T-LBL patients’ outcome. Interestingly, we pinpointed JAK2 Y1007-1008 as a potential prognosis marker as well as a therapeutic target in poor prognosis patients. Hence, the hyperactivation of the JAK1/2-STAT6 pathway characterizes these latter patients. Moreover, we functionally demonstrated that STAT6 hyperactivation contributes to therapy resistance by binding the glucocorticoid receptor, thus inhibiting its transcriptional activity. This was further confirmed by specific STAT6 gene silencing followed by dexamethasone treatment. Finally, JAK1/2-STAT6 pathway inhibition by ruxolitinib, an FDA approved drug, in cell line models and in one T-LBL primary sample led to cell proliferation reduction and increased apoptosis. Globally, our results identify a new potential prognostic marker and suggest a novel therapeutic approach to overcome therapy resistance in pediatric T-LBL patients.

Second malignant neoplasms after treatment of non-Hodgkin's lymphoma-a retrospective multinational study of 189 children and adolescents

Data on the spectrum of second malignant neoplasms (SMNs) after primary childhood non-Hodgkin's lymphoma (NHL) are scarce. One-hundred-and-eighty-nine NHL patients diagnosed in a 30 years period of 1980-2010 developing an SMN were retrieved from 19 members of the European Intergroup for Childhood NHL and/or the international Berlin-Frankfurt-Münster Study Group. Five subgroups of SMNs were identified: (1) myeloid neoplasms (n = 43; 23%), (2) lymphoid neoplasms (n = 51; 27%), (3) carcinomas (n = 48; 25%), (4) central nervous system (CNS) tumors (n = 19; 10%), and (5) "other" SMNs (n = 28; 15%). In 37 patients (20%) preexisting disorders were reported with 90% having any kind of cancer predisposition syndrome (CPS). For the 189 primary NHL patients, 5-year overall survival (OS) after diagnosis of an SMN was 56 ± 4%, being worst for patients with preexisting disorders at 28 ± 8%. Five-year OS rates were 38 ± 8%, 59 ± 7%, 79 ± 8%, 34 ± 12%, and 62 ± 11%, respectively, for patients with myeloid and lymphoid neoplasms, carcinomas, CNS tumors, and "other" SMNs (p < 0.0001). Patients with SMNs after childhood NHL having a reported CPS, mostly mismatch repair disorders, carried a very poor prognosis. Moreover, although outcome was favorable in some subtypes of SMNs after childhood NHL (carcinomas, lymphoid neoplasms), other SMNs such as myeloid neoplasms and CNS tumors had a dismal prognosis.

Lymphoblastic lymphoma in children and adolescents: review of current challenges and future opportunities

Lymphoblastic lymphoma (LBL) is the second most common type of Non-Hodgkin Lymphoma (NHL) in childhood and adolescence, accounting for 25-35% of all cases. The majority, 70-80%, is of T-lymphoblastic origin while 20-25% arise from B lymphoblasts. With current therapy, the event-free and overall survivals for paediatric LBL patients now exceeds 80%. Therapy, especially in T-LBL with large mediastinal tumours, is challenging, with both significant morbidity and late sequela. An additional challenge is the dismal prognosis of patients with refractory or relapsed disease. This review article will focus on the growing knowledge of the pathogenesis and biology of LBL, recent advances and challenges in the therapy of LBL, and ongoing and future efforts and opportunities in optimizing therapy and developing novel targeted treatment approaches.

Lymphoma in Adolescents and Young Adults: Current Perspectives

Lymphomas in adolescents and young adults represent approximately one quarter of all cancers in this age group. Historically, adolescent and young adult cancer patients represent a unique population with diverging issues surrounding psychosocial hardships/barriers, economics, and lack of standardization of therapeutic approaches.Furthermore, the biologic differences within the adolescent and young adult population seen in various lymphoma subtypes likely play a role in overall outcomes for this group. Without an organized approach to clinical and translational research for adolescent and young adult patients within specialized treatment centers, this population may continue to experience inferior results. Here we look at the current perspectives of adolescent and young adult lymphomas with respect to disease biology, clinical characteristics, treatment, and prognosis of this unique lymphoma population.

Treatment Options for Paediatric Anaplastic Large Cell Lymphoma (ALCL): Current Standard and beyond

Anaplastic Lymphoma Kinase (ALK)-positive Anaplastic Large Cell Lymphoma (ALCL), remains one of the most curable cancers in the paediatric setting; multi-agent chemotherapy cures approximately 65–90% of patients. Over the last two decades, major efforts have focused on improving the survival rate by intensification of combination chemotherapy regimens and employing stem cell transplantation for chemotherapy-resistant patients. More recently, several new and ‘renewed’ agents have offered the opportunity for a change in the paradigm for the management of both chemo-sensitive and chemo-resistant forms of ALCL. The development of ALK inhibitors following the identification of the EML4-ALK fusion gene in Non-Small Cell Lung Cancer (NSCLC) has opened new possibilities for ALK-positive ALCL. The uniform expression of CD30 on the cell surface of ALCL has given the opportunity for anti-CD30 antibody therapy. The re-evaluation of vinblastine, which has shown remarkable activity as a single agent even in the face of relapsed disease, has led to the consideration of a revised approach to frontline therapy. The advent of immune therapies such as checkpoint inhibition has provided another option for the treatment of ALCL. In fact, the number of potential new agents now presents a real challenge to the clinical community that must prioritise those thought to offer the most promise for the future. In this review, we will focus on the current status of paediatric ALCL therapy, explore how new and ‘renewed’ agents are re-shaping the therapeutic landscape for ALCL, and identify the strategies being employed in the next generation of clinical trials.

Outcome and Toxicity Patterns in Children and Adolescents with Non-Hodgkin Lymphoma: A Single Institution Experience

Background

The incidence and biology of non-Hodgkin lymphoma (NHL) vary according to age. Some data suggest that the impact of age in pediatric and adolescent NHL patients depends on the histological subtype. Objectives: We aimed to analyze the impact of age at diagnosis on clinical characteristics and treatment-related toxicity in children and adolescents with NHL.

Methods

Retrospective review of medical records of children and adolescents diagnosed with NHL at the Hospital for Sick Children, Toronto, between January 1995 and December 2008.

Results

164 children were diagnosed with NHL during the study period, with a median age at diagnosis of 10 years. With a median follow-up of 6.2 years, 5-year OS in patients aged <15 and 15–18 years was 89± 2% vs 82% ± 6%, respectively (P = 0.30), and 5-year EFS was 84% ± 3% vs. 77% ± 7% (P= 0.37). In Burkitt’s lymphoma (BL) and lymphoblastic lymphoma (LL) there was a trend towards better outcomes in children compared to adolescents, with EFS of 91% ± 4% vs. 75% ± 15%, respectively in BL (P= 0.17), and 82% ± 7% vs. 51.4% ± 2% respectively in LL (P= 0.16). Late effects occurred in 21 patients (12.8%).

Conclusions

Children with NHL aged < 15 years tend to have better survival rates and similar long-term toxicity than adolescents aged 15–18 years.

Results and conclusions of the European Intergroup EURO-LB02 trial in children and adolescents with lymphoblastic lymphoma

In the European Intergroup EURO-LB02 trial, children and adolescents with lymphoblastic lymphoma underwent the non-Hodgkin lymphoma Berlin-Frankfurt-Münster protocol without prophylactic cranial radiotherapy. The primary aims of this trial were to test whether replacing prednisone with dexamethasone during induction increases event-free survival in the subgroups with T-cell lymphoblastic lymphoma and whether therapy duration could be reduced from 24 to 18 months (factorial design, randomizations). These questions could not be answered due to premature closure of the trial. Here we report on the secondary aims of the trial: whether the results of the NHL-BFM90 study could be reproduced and evaluation of disease features and prognostic factors. Three hundred and nineteen patients (66 with precursor B-cell lymphoblastic lymphoma, 233 with T-cell lymphoblastic lymphoma, 12 with mixed phenotype, 8 not classifiable) were enrolled. In induction, 215 patients received prednisone and 104 patients received dexamethasone. The median follow-up was 6.8 years (range, 3.0–10.3). The 5-year event-free survival was 82±2% [12 toxic deaths, 5 secondary malignancies, 43 non-response/relapse (central nervous system n=9; all received prednisone during induction)]. The event-free survival rate was 80±5% for patients with precursor B-cell lymphoblastic lymphoma, 82±3% for those with T-cell lymphoblastic lymphoma, and 100% for patients with a mixed phenotype. During induction, significantly more grade III/IV toxicities were observed in patients receiving dexamethasone, resulting in significant treatment delays. The number of toxic deaths did not differ significantly. The only variable associated with outcome was performance status at diagnosis. The 90% event-free survival rate for patients with T-cell lymphoblastic lymphoma shown in study NHL-BFM90 was not replicated, mainly due to more toxic deaths and central nervous system relapses. Dexamethasone in induction may prevent central nervous system relapse more effectively than prednisone but produces a higher burden of toxicity. (#NCT00275106).

Non-Hodgkin lymphoma and pre-existing conditions: spectrum, clinical characteristics and outcome in 213 children and adolescents

Children and adolescents with pre-existing conditions such as DNA repair defects or other primary immunodeficiencies have an increased risk of non-Hodgkin lymphoma. However, large-scale data on patients with non-Hodgkin lymphoma and their entire spectrum of pre-existing conditions are scarce. A retrospective multinational study was conducted by means of questionnaires sent out to the national study groups or centers, by the two largest consortia in childhood non-Hodgkin lymphoma, the European Intergroup for Childhood non-Hodgkin Lymphoma, and the international Berlin-Frankfurt-Münster Study Group. The study identified 213 patients with non-Hodgkin lymphoma and a pre-existing condition. Four subcategories were established: a) cancer predisposition syndromes (n=124, 58%); b) primary immunodeficiencies not further specified (n=27, 13%); c) genetic diseases with no increased cancer risk (n=40, 19%); and d) non-classifiable conditions (n=22, 10%). Seventy-nine of 124 (64%) cancer predispositions were reported in groups with more than 20 patients: ataxia telangiectasia (n=32), Nijmegen breakage syndrome (n=26), constitutional mismatch repair deficiency (n=21). For the 151 patients with a known cancer risk, 5-year event-free survival and overall survival rates were 40%±4% and 51%±4%, respectively. Five-year cumulative incidences of progression/relapse and treatment-related death as a first event were 22%±4% and 24%±4%, respectively. Ten-year incidence of second malignancy was 24%±5% and 7-year overall survival of the 21 patients with a second malignancy was 41%±11%. Patients with non-Hodgkin lymphoma and pre-existing conditions have an inferior survival rate with a large proportion of therapy-related deaths compared to patients with non-Hodgkin lymphoma and no pre-existing conditions. They may require special vigilance when receiving standard or modified/reduced-intensity chemotherapy or when undergoing allogeneic stem cell transplantation.

Molecular genetics of childhood, adolescent and young adult non-Hodgkin lymphoma

Molecular genetic abnormalities are ubiquitous in non-Hodgkin lymphoma (NHL), but genetic changes are not yet used to define specific lymphoma subtypes. Certain recurrent molecular genetic abnormalities in NHL underlie molecular pathogenesis and/or are associated with prognosis or represent potential therapeutic targets. Most molecular genetic studies of B- and T-NHL have been performed on adult patient samples, and the relevance of many of these findings for childhood, adolescent and young adult NHL remains to be demonstrated. In this review, we focus on NHL subtypes that are most common in young patients and emphasize features actually studied in younger NHL patients. This approach highlights what is known about NHL genetics in young patients but also points to gaps that remain, which will require cooperative efforts to collect and share biological specimens for genomic and genetic analyses in order to help predict outcomes and guide therapy in the future.

Detection and role of minimal disseminated disease in children with lymphoblastic lymphoma: The AIEOP experience

BACKGROUND

The use of intensive chemotherapy regimens in children with lymphoblastic lymphoma (LBL) has significantly improved outcome, but the salvage rate for these patients is still poor. The aim of this study was to evaluate the prognostic value of minimal disseminated disease (MDD), studied by multiparametric flow cytometry (MFC), in pediatric patients with T- and B-lineage LBL.

PROCEDURE

We examined bone marrow (BM) and peripheral blood (PB) samples from a series of 65 children affected by T- (52) and B-lineage (13) LBL using an MFC method; 10 of them were also analyzed for clonality of T-cell receptor gene rearrangements.

RESULTS

MDD was detected in 49% (32/65) of BM samples, whereas only 21% (14/65) were positive at standard morphological evaluation. Findings from MFC analyses of paired BM and PB samples were highly concordant. We analyzed the prognostic significance of MDD results detected at diagnosis in morphologically negative patients, as almost all relapsed cases (10/11) did not have any morphological involvement of BM at diagnosis. Using an MDD cut-off level of 3% by FCM (75th percentile), 5-year event-free survival (EFS) was 60% (SE ± 22) for patients with MDD >3% LBL cells versus 83% (SE ± 6) for the remaining patients (P = 0.04). No statistically significant difference in EFS was observed between LBL patients considering all the other clinical characteristics.

CONCLUSIONS

Our data demonstrated that MDD studied at diagnosis by MFC could represent a useful prognostic tool in childhood LBL and further application for better stratification is warranted.

Non-Hodgkin lymphoma in children with an associated inherited condition: A retrospective analysis of the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP)

BACKGROUND

Inherited conditions affecting genetic aberration, viral oncogenesis, reduced immune surveillance, and long-lasting antigen stimulation may build the way to lymphomagenesis in humans.

METHODS

We extracted from the database of 4 consecutive trials for pediatric non-Hodgkin lymphoma (NHL) all cases with an associated genetic disease.

RESULTS

Among 1,430 patients, 34 (2.4%) had an associated inherited condition and a mature B-lineage (n = 28), anaplastic large cell lymphoma (n = 4), or T-lineage (n = 2) NHL. Their median age at the diagnosis was 9.3 years (range, 2.6-17.8 years). In 14 cases (41%) the underlying condition was considered to be a potential cause for undue toxicity if the expected therapy was applied. Thus, treatment modification had been planned in advance. The overall survival was 89% (standard error [SE] 1%), 73% (SE 10%), and 73% (SE 23%) at 3 years for registered patients with no inherited condition associated, with genetic abnormalities and with underlying condition causing an immune deficiency, respectively (P = 0.003).

CONCLUSION

In our cohort, patients with NHL with an underlying constitutional condition represent the 2.4% of the cases. In the subset of patients with primary immune deficiency, which may have contributed to lymphomagenesis, allogeneic hematopoietic stem cell transplantation may be required. In the remaining patients, the association with lymphoma remains apparently unexplained and could be not causative. Detailed reporting of such cases may contribute to disclose even rare and fully unexpected association, which may have implications for research in the field of lymphomagenesis.

Non-Hodgkin Lymphoma in Children and Adolescents: Progress Through Effective Collaboration, Current Knowledge, and Challenges Ahead

Non-Hodgkin lymphoma is the fourth most common malignancy in children, has an even higher incidence in adolescents, and is primarily represented by only a few histologic subtypes. Dramatic progress has been achieved, with survival rates exceeding 80%, in large part because of a better understanding of the biology of the different subtypes and national and international collaborations. Most patients with Burkitt lymphoma and diffuse large B-cell lymphoma are cured with short intensive pulse chemotherapy containing cyclophosphamide, cytarabine, and high-dose methotrexate. The benefit of the addition of rituximab has not been established except in the case of primary mediastinal B-cell lymphoma. Lymphoblastic lymphoma is treated with intensive, semi-continuous, longer leukemia-derived protocols. Relapses in B-cell and lymphoblastic lymphomas are rare and infrequently curable, even with intensive approaches. Event-free survival rates of approximately 75% have been achieved in anaplastic large-cell lymphomas with various regimens that generally include a short intensive B-like regimen. Immunity seems to play an important role in prognosis and needs further exploration to determine its therapeutic application. ALK inhibitor therapeutic approaches are currently under investigation. For all pediatric lymphomas, the intensity of induction/consolidation therapy correlates with acute toxicities, but because of low cumulative doses of anthracyclines and alkylating agents, minimal or no long-term toxicity is expected. Challenges that remain include defining the value of prognostic factors, such as early response on positron emission tomography/computed tomography and minimal disseminated and residual disease, using new biologic technologies to improve risk stratification, and developing innovative therapies, both in the first-line setting and for relapse.

Long-term results of the AIEOP LNH-97 protocol for childhood lymphoblastic lymphoma

BACKGROUND

Treatment intensification was considered a suitable strategy to increase the cure rate of lymphoblastic lymphoma (LBL) in children.

PROCEDURE

The AIEOP LNH-97 trial was run between 1997 and 2007 for newly diagnosed LBL in patients aged less than 18 years. Treatment schedule was based on the previous, LSA2-L2 derived, AIEOP LNH-92 protocol. Modifications included: increased dose of upfront cyclophosphamide and methotrexate, use of l-Asparaginase during induction therapy, intensive block therapy for slow responders, and late intensification ("Reinduction") for patients with advanced stage disease. Total therapy duration was 12 months for stage I and II, and 24 months for stage III and IV. Central nervous system prophylaxis did not include cranial irradiation.

RESULTS

114 eligible patients were enrolled, 84 males and 30 females; median age was 9 years. Complete remission was obtained in 98% of patients. After a median follow-up time of seven years, 29 patients failed due to progression of disease (n = 2), relapse (n = 25), or second malignancy (n = 2). The 7-year overall survival was 82% (standard error [SE] 4%) and the 7-year event-free survival was 74% (SE 4%). No subgroup showed significantly different event free survival. None of the patients died of front line chemotherapy-related toxicity.

CONCLUSIONS

Treatment intensification was associated with good outcome in children and adolescents with LBL, with limited toxicity. Prognosis after relapse was better for patients who underwent allogeneic hematopoietic stem cell transplantation. Measurements of biological markers and treatment response are necessary for achieving further improvement through more accurate identification and stratification of patients at risk of disease relapse.

Clinical outcome of childhood lymphoblastic lymphoma in Shanghai China 2001-2010

BACKGROUND

This retrospective cohort study analysed the clinical characteristics and outcomes of patients with childhood lymphoblastic lymphoma (LBL) treated in Shanghai, China.

PROCEDURE

From 2001 to 2010, 108 evaluable patients ≤16 years of age who were newly diagnosed with biopsy-proven LBL were treated with one of three treatment protocols: CCCG-99, SCMC-T-NHL-2002, or LBL-CHOF-2006.

RESULTS

Two patients had Stage I disease, 5 had Stage II, 55 had Stage III, and 46 had Stage IV. The immunophenotype was T-cell LBL in 92 patients (85.2%) and precursor B-cell LBL in 16 (14.8%). The abandonment rate was 11.5%. Twenty-five patients (23.2%) suffered from resistant disease, including 1 with isolated central nervous system (CNS) relapse. At a median follow-up of 40.4 months (range, 0-114 months), the 5-year probability of event-free survival (pEFS) was 63.9 ± 4.6% in all patients. The 5-year pEFS for patients with pB-LBL was better than for patients with T-LBL (100% vs. 61.3 ± 5.1%, P = 0.007). Patients who had achieved complete remission on day 33 of induction had significantly better pEFS than those who had not (78.8 ± 4.6% vs. 28.2 ± 9.0%, P = 0.000). Three of 25 patients who experienced resistant disease were alive at the end of the study period.

CONCLUSIONS

The abandonment rate was lower for patients with LBL than for patients with acute lymphoblastic leukemia. Prophylactic cranial radiation can be omitted for patients with LBL even when advanced-stage disease is present, as intensive systemic chemotherapy with intrathecal therapy is sufficient to prevent CNS relapse. The survival of patients with resistant disease was very poor.

Should children with non-Hodgkin lymphoma be treated with different protocols according to histopathologic subtype?

BACKGROUND

The New York protocol, primarily developed to treat children with high-risk acute lymphoblastic leukemia (ALL), is characterized by early intensive chemotherapy followed by less intensive pulse chemotherapy during maintenance. This study was performed to evaluate the efficacy of this protocol in children with non-Hodgkin lymphoma (NHL), irrespective of histopathologic subtype.

PROCEDURE

From January 1996 to December 2011, 146 newly diagnosed children and adolescents with NHL were treated with the modified New York protocol. Treatment duration was determined according to the stage.

RESULTS

The 5-year failure-free survival (FFS), event-free survival (EFS), and overall survival (OS) rates were 86.7 ± 2.9%, 79.1 ± 3.5%, and 84.7 ± 3.1%, respectively. The 5-year FFS for patients with mature B-cell lymphoma, T-cell and NK-cell lymphoma (T/NK-cell lymphoma), and lymphoblastic lymphoma were 95.4 ± 2.6%, 76.1 ± 7.0%, and 82.1 ± 6.6%, respectively. In multivariate analysis, T/NK-cell lymphoma and non-complete response (non-CR) at the end of induction chemotherapy were associated with a significant increase in treatment failure rate (relative risk [RR], 4.5, P = 0.03, and RR, 5.0, P = 0.002).

CONCLUSION

The protocol appears to be efficacious in the treatment of children and adolescents with NHL, irrespective of histopathologic subtype. Achievement of CR after intensive induction chemotherapy was an important prognostic factor. Early response to treatment may be used to stratify risk groups and modify therapy in children with NHL.

Lymphoblastic lymphoma in childhood and adolescence

Lymphoblastic lymphoma (LBL) are thought to derive from immature precursor T-cells or B-cells. LBL are the second most common subtype of Non-Hodgkin Lymphoma (NHL) in children and adolescents. LBL are closely related to acute lymphoblastic leukemia (ALL), the most common type of cancer in children. Using ALL-type treatment regimen to treat children with LBL was an important development in the treatment of LBL. During the last decades, several systematic clinical trials contributed to the controlled optimization of treatment. Today event-free survival (EFS) can be achieved for 75-90% of patients. However, acute and long-term toxicity, the lack of prognostic parameters and the poor outcome for patients who suffer from refractory or relapsed LBL remain highly relevant subjects for improvement. To date, the pathogenesis of LBL is poorly understood. Learning more about the biology and pathogenesis of LBL might pave the way for targeted treatment to improve survival especially in relapsed and refractory patients.

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.

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.

Outcome of newly diagnosed children and adolescents with localized lymphoblastic lymphoma treated on Children's Oncology Group trial A5971: a report from the Children's Oncology Group

BACKGROUND

Localized lymphoblastic lymphoma (LL) is rare in pediatric patients. We report the 5-year event-free survival (EFS) and overall survival (OS) for children and adolescents with localized LL treated on a uniform regimen based on Children's Cancer Group (CCG) leukemia therapy (COG A5971).

PROCEDURE

From June 2000 to October 2005, the study enrolled 60 patients >12 months old with Murphy stages I or II LL. Central review confirmed 56 eligible patients. Treatment consisted of 24 months of CCG BFM without day 28 intrathecal methotrexate in maintenance therapy or prophylactic cranial radiation.

RESULTS

Most patients had pre-B immunophenotype (75%). At a median follow-up of 5.9 years (range 1.4-9.3 years), the 5-year EFS was 90% [95% confidence interval (CI), 78-96%] and the 5-year OS was 96% (95% CI, 84-99%). Stage (I vs. II), immunophenotype, elevated LDH > institutional normal, or primary site did not impact outcome. Five relapses occurred-none in the CNS and none in patients with pre-T lymphoblastic disease. Patients tolerated treatment well with no toxic deaths.

CONCLUSION

Outcomes of pediatric patients with localized LL treated with 2 years of intensive acute lymphoblastic leukemia (ALL)-type therapy was excellent and is similar to the outcome for standard risk ALL treated less intensively. CNS prophylaxis was adequate with limited intrathecal methotrexate and no radiation. Future studies should identify biologic prognostic factors or biomarkers for pediatric patients with LL, explore less intensive treatment for patients with localized disease, and explore novel immunophenotype directed therapies.

Gastric Burkitt's lymphoma in a child: A rare case

Burkitt's lymphoma (BL) is a high-grade lymphoma which represents 8-10% of all tumors in individuals younger than 15 years old. It may occur as an abdominal tumor, which in rare cases may include gastric mucosa, although in most cases, the tumor is located in the ileum or cecum. Primary gastric lymphoma constitutes as low as 1.48% of all gastric cancers in children. In this study, we described a case of gastric BL in a 4-year-old child, presenting discontinuous abdominal pain, weight loss, constipation and irritability. Despite its rarity in children, this tumor should be treated aggressively and long-term survival has been reported.

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.

Pediatric non-Hodgkin lymphoma: a retrospective 14-year experience with Berlin-Frankfurt-Münster (BFM) protocols from a tertiary care hospital in Serbia

Use of current intensive chemotherapy protocols in pediatric non-Hodgkin lymphoma (NHL) in high-income countries resulted in event-free survival (EFS) rates ranging from 80 to 90%. The results are inferior in less privileged countries with limited resources for medical care. There are no reports about comprehensive data analysis in pediatric NHL in Serbia. A retrospective study was carried out at University Children's Hospital, Belgrade, in children aged less than 18 years diagnosed with non-Hodgkin lymphoma from 1997 to 2011. Fifty-seven children were eligible for analysis. Fourteen were diagnosed with lymphoblastic lymphoma, 38 with mature B-cell NHL (B-NHL), and 5 with anaplastic large-cell lymphoma. Mean age at diagnosis was 9.2 years, with male to female ratio 2.35:1. Children were treated according to Berlin-Frankfurt-Münster (BFM) protocols. With median follow-up of 59.3 months, 5-year probability of EFS was 84.1% for all patients, whereas overall survival was 93%. These results with BFM protocol administration, although inferior to leading international groups, reflect good treatment outcome in our patients. To the best of the authors' knowledge, this article presents the first results regarding treatment and survival of childhood NHL in Serbia.

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.