Summary
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.
Total body irradiation (TBI) before allogeneic hematopoietic stem cell transplantation (HSCT) in pediatric patients with acute lymphoblastic leukemia (ALL) is efficacious, but long-term side effects ...are concerning. We investigated whether preparative combination chemotherapy could replace TBI in such patients.
FORUM is a randomized, controlled, open-label, international, multicenter, phase III, noninferiority study. Patients ≤ 18 years at diagnosis, 4-21 years at HSCT, in complete remission pre-HSCT, and with an HLA-compatible related or unrelated donor were randomly assigned to myeloablative conditioning with fractionated 12 Gy TBI and etoposide versus fludarabine, thiotepa, and either busulfan or treosulfan. The noninferiority margin was 8%. With 1,000 patients randomly assigned in 5 years, 2-year minimum follow-up, and one-sided alpha of 5%, 80% power was calculated. A futility stopping rule would halt random assignment if chemoconditioning was significantly inferior to TBI (EudraCT: 2012-003032-22; ClinicalTrials.gov: NCT01949129).
Between April 2013 and December 2018, 543 patients were screened, 417 were randomly assigned, 212 received TBI, and 201 received chemoconditioning. The stopping rule was applied on March 31, 2019. The median follow-up was 2.1 years. In the intention-to-treat population, 2-year overall survival (OS) was significantly higher following TBI (0.91; 95% CI, 0.86 to 0.95;
< .0001) versus chemoconditioning (0.75; 95% CI, 0.67 to 0.81). Two-year cumulative incidence of relapse and treatment-related mortality were 0.12 (95% CI, 0.08 to 0.17;
< .0001) and 0.02 (95% CI, < 0.01 to 0.05;
= .0269) following TBI and 0.33 (95% CI, 0.25 to 0.40) and 0.09 (95% CI, 0.05 to 0.14) following chemoconditioning, respectively.
Improved OS and lower relapse risk were observed following TBI plus etoposide compared with chemoconditioning. We therefore recommend TBI plus etoposide for patients > 4 years old with high-risk ALL undergoing allogeneic HSCT.
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.
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).
The prognosis of germinal center–derived B-cell (GCB) lymphomas, including follicular lymphoma and diffuse large-B-cell lymphoma (DLBCL), strongly depends on age. Children have a more favorable ...outcome than adults. It is not known whether this is because of differences in host characteristics, treatment protocols, or tumor biology, including the presence of chromosomal alterations. By screening for novel IGH translocation partners in pediatric and adult lymphomas, we identified chromosomal translocations juxtaposing the IRF4 oncogene next to one of the immunoglobulin (IG) loci as a novel recurrent aberration in mature B-cell lymphoma. FISH revealed 20 of 427 lymphomas to carry an IG/IRF4-fusion. Those were predominantly GCB-type DLBCL or follicular lymphoma grade 3, shared strong expression of IRF4/MUM1 and BCL6, and lacked PRDM1/BLIMP1 expression and t(14;18)/BCL2 breaks. BCL6 aberrations were common. The gene expression profile of IG/IRF4-positive lymphomas differed from other subtypes of DLBCL. A classifier for IG/IRF4 positivity containing 27 genes allowed accurate prediction. IG/IRF4 positivity was associated with young age and a favorable outcome. Our results suggest IRF4 translocations to be primary alterations in a molecularly defined subset of GCB-derived lymphomas. The probability for this subtype of lymphoma significantly decreases with age, suggesting that diversity in tumor biology might contribute to the age-dependent differences in prognosis of lymphoma.
The activity of rituximab in pediatric B-cell non-Hodgkin's lymphoma (B-NHL) has not yet been determined. We conducted a phase II window study to examine activity and tolerability of rituximab in ...newly diagnosed pediatric B-NHL.
Patients younger than age 19 years with CD20(+) B-NHL with at least one measurable site were eligible. Treatment consisted of rituximab at 375 mg/m(2) administered intravenously on day 1; concomitant therapy consisted of rasburicase, intrathecally (IT) triple drug (methotrexate, cytarabine, and prednisolone) on days 1 and 3 for CNS-positive patients and steroids only for anaphylaxis. Response criterion was the product of the two largest perpendicular diameters of one to three lesions and/or the percentage of blasts in bone marrow (BM) or peripheral blood (PB) within 24 hours before rituximab and on day 5. Responders had > or = 25% decrease of at least one lesion or BM or PB blasts and no disease progress at other sites. Response rate (RR) was set at 45% for unfavorable activity or at 65% for favorable activity.
From April 2004 to August 2008, 136 patients were enrolled. National Cancer Institute Common Toxicity Criteria 3/4 toxicities attributable to rituximab were general condition, 15%; fatigue, 13%; anaphylaxis, 7%; infection, 3%; glutamic-oxaloacetic transaminase/glutamic-pyruvic transaminase, 8%; no capillary leakage; and no toxic death. Forty-nine patients were not evaluable for response because of withdrawal from the study (n = 16), IT therapy in CNS-negative patients (n = 8), corticosteroid treatment (n = 3), technical inadequacy of response evaluation (n = 21), or no evaluable lesion (n = 1). Of 87 evaluable patients, 36 were responders (RR, 41.4%; 95% CI, 31% to 52%); among them, 27 of 67 with Burkitt lymphoma and seven of 15 with diffuse large B-cell lymphoma. A response was more frequently observed in BM (12 of 18) compared with solid tumor lesions (36 of 108; P = .007).
Rituximab is active as a single-agent in pediatric B-NHL even though the RR was lower than requested in the phase II plan.
Little is known about the outcome of pediatric patients with lymphoblastic lymphoma (LBL) who suffer from progressive disease or relapse.
We analyzed the pattern of LBL relapses after current ...non-Hodgkin's lymphoma Berlin-Frankfurt-Muenster (BFM) frontline therapy between April 1990 and March 2003. Relapse therapy was according to acute lymphoblastic leukemia (ALL) -Relapse-BFM protocols or ALL-BFM protocols for high-risk patients.
Twenty-eight (11%) of 251 registered patients with precursor T-cell LBL (T-LBL) and six (8%) of 73 patients with precursor B-cell LBL (pB-LBL) suffered from relapse. Of the 28 patients with T-LBL, one died from infection during relapse chemotherapy, 18 failed to achieve stable remission and died from disease progression, and nine reached allogeneic stem-cell transplantation (SCT). Two of these nine patients who underwent SCT died from transplantation-associated toxicity, three died from disease progression, and four are still alive. These four patients are in second remission of their lymphoma for 48, 68, 125, and 131 months, respectively, after allogeneic SCT. One of the four patients developed colon adenocarcinoma 47 months after SCT. Of the six patients with pB-LBL who experienced relapse, one patient died as a result of toxicity of relapse chemotherapy, two died from disease progression after chemotherapy, and three received allogeneic SCT. Of these, two died from subsequent disease progression, and one is still alive 57 months after allogeneic SCT.
Using modern conventional therapy in the frontline treatment of LBL, 10% of patients suffer from progressive disease or relapse. Because of the extremely poor reinduction success, the salvage rate for these patients is poor, with only a 14% (SE = 6%) overall survival. Long-term survival was only achieved in those few patients who were able to undergo an allogeneic SCT.