Childhood and adolescent non-Hodgkin lymphoma: new insights in biology and critical challenges for the future

Update on FDG-PET in pediatric lymphoma

Lymphoma represent the third most common malignant disease in childhood and adolescence. They are divided into pediatric Hodgkin lymphoma (P-HL) and pediatric non-Hodgkin lymphoma (P-NHL). In P-HL, excellent cure rates are achieved through combined modality treatment using chemotherapy and radiotherapy. For more than 20 years, FDG-PET has been an integral part of the treatment and guides its intensity through improved staging and precise assessment of chemotherapy response. In P-NHL, good cure rates are achieved with chemotherapy alone. At present FDG-PET plays only a subordinate role in the treatment setting. Its potential to contribute to treatment management is far from being fully utilised. In this article, the current status of FDG-PET in pediatric lymphoma is presented in detail. The core elements are the sections on staging and response assessment. In addition, challenges and pitfalls are discussed and future developments are outlined.

30 Years of Experience with Non-Hodgkin Lymphoma in Children and Adolescents: a retrospective cohort study

OBJECTIVE

Describe the clinical and demographic characteristics of pediatric patients with non-Hodgkin's lymphoma (NHL) enrolled in a tertiary unit of Pediatric Hematology between 1982-2015.

PATIENTS AND METHODS

A retrospective cohort study of 140 patients aged 16 years or less with NHL. Demographic characteristics, data on diagnosis, and outcomes were analyzed. The overall survival (OS) analysis and stratification by the most frequent histological subtypes were performed using the Kaplan-Meier method.

RESULTS

One hundred and thirty-six patients with de novo NHL and four with NHL as a second malignancy were analyzed. The median age at diagnosis was 6.4 years (interquartile range, 4.2 to 11.1 years); 101 patients were males. Four patients had primary immunodeficiency, four had human immunodeficiency virus, two post-liver transplantation, and one had autoimmune lymphoproliferative syndrome. The most frequent histological type was NHL of mature B- cell (B-NHL-B; 67.1%), with Burkitt's lymphoma being the most frequent subtype, and lymphoblastic lymphoma (LBL, 21.4%). The main clinical manifestation at the diagnosis was abdominal tumors (41.4%). During the follow-up time, 13 patients relapsed, but five of them reached a second remission. Thirty-five patients died, and 103 remained alive in clinical remission. No contact was possible for two patients. The OS at 5 years was 74.5% (± 3.8%). The OS estimated for patients with LBL, NHL-B, and the remaining was 80.4%±7.9%, 72.8%±4.7%, and 74.5%±11%, respectively (P = 0.58).

CONCLUSION

Our results are comparable with cohorts from other middle-income countries.

Pediatric non-Hodgkin lymphoma: Characteristics, stratification, and treatment at a single institute in Thailand

BACKGROUND

In the modern era of chemotherapy, the outcome of pediatric non-Hodgkin lymphoma (NHL) continues to improve internationally. Limited data such as information on epidemiology and survival, however, are available in Asian countries.

METHODS

Children (≤15 years old) diagnosed with histologically proven NHL from 1998 to 2014 were retrospectively analyzed.

RESULTS

In total, 114 patients were enrolled; they were predominantly male (65.8%) and had advanced disease (stage III, IV; 71.9%). Of these, 22.8% had Burkitt lymphoma, 20.2% had diffuse large B-cell lymphoma, 21.1% had lymphoblastic lymphoma, 20.2% had large cell lymphoma, and 15.8% had peripheral T-cell lymphoma. Twenty-nine patients died, especially of uncontrolled disease (62.1%) and infection (20.7%). During a median follow up of 78.4 months, Kaplan-Meier 5 year event-free and overall survival rates were 71.5% ± 4.3% and 74.8% ± 4.1%, respectively, regardless of subtype. B symptoms (i.e. systemic symptoms of fever, night sweats, and weight loss that can be associated with both Hodgkin's lymphoma and non-Hodgkin's lymphoma) and advanced disease had a significant negative impact on 5 year survival. No other prognostic factor was found, but survival tended to have a negative correlation with age.

CONCLUSIONS

Pediatric NHL is aggressive, with a high prevalence of peripheral T-cell lymphoma. The present treatment stratification seems to be effective compared with that used in developed countries.

Patients over 40 years old with precursor T-cell lymphoblastic lymphoma have different prognostic factors comparing to the youngers

This study aimed to analyze the clinical characteristics and prognostic factors of patients, divided into over 40-year-old group or not, with precursor T-cell lymphoblastic lymphoma (Pre-T-LBL). Based on the retrospective analysis of the clinical data of 59 patients with Pre-T-LBL during the period from December 2010 to December 2015, albumin level, anemia, pleural or pericardial effusion, protocol, therapy response, mediastinal mass, lactate dehydrogenase (LDH), and international prognostic index (IPI) or age-adjusted international prognostic index (aaIPI) were summarized. For patients aged <40 years, factors correlating with poor progression-free survival (PFS) were pleural or pericardial effusion, regimen, albumin level and therapy response. Pleural or pericardial effusion, aaIPI score, regimen, LDH increased, albumin level, therapy response and mediastinal mass were all related with poor overall survival (OS). In the patients aged ≥40 years, only anemia associated with PFS. However, anemia, involvement of bone marrow and therapeutic response were all related with poor OS. In conclusion, the patients with Pre-T-LBL are characterized by a low incidence and bad prognosis. Different prognostic factors can be discovered for patients over 40-year-old with Pre-T-LBL comparing to the youngers. New prognostic evaluation factors should be explored for patients ≥40 years old.

Outcome of children and adolescents with lymphoblastic lymphoma

INTRODUCTION

lymphoblastic lymphoma (LBL) is the second most common subtype of non-Hodgkin lymphoma in children. The aim of this study was to characterize the clinical course of children and adolescents with LBL treated at a tertiary center.

METHODS

this is a retrospective cohort study of 27 patients aged 16 years or younger with LBL admitted between January 1981 and December 2013. Patients were treated according to the therapy protocol used for acute lymphoblastic leucemia. Diagnosis was based on biopsy of tumor and/or cytological examination of pleural effusions. The overall survival was analyzed using the Kaplan-Meier method.

RESULTS

the median age at diagnosis was 11.6 years (interquartile range, 4.6- 13.8). LBL had T-cell origin in 16 patients (59%). The most common primary manifestation in T-cell LBL was mediastinal involvement, in 9 patients (56%). Intra-abdominal tumor was the major site of involvement in patients with precursor B-LBL. Most patients had advanced disease (18 patients - 67%) at diagnosis. Twenty-four patients (89%) achieved complete clinical remission. After a median follow-up of 43 months (interquartile range, 6.4-95), 22 patients (81%) were alive in first complete remission. Five children (18.5%) died, three of them soon after admission and two after relapsing. The probability of survival at five years for 20 patients with de novo LBL was 78% (SD 9.4).

CONCLUSION

our findings confirm the favorable prognosis of children with LBL with an intensive chemotherapy regimen derived from ALL therapy.

Primary T-cell lymphoblastic lymphoma in the middle ear

T-cell lymphoblastic lymphoma (T-LBL) is a highly aggressive lymphoma characterized by precursor T-cell malignancy and lymphadenopathy or mediastinal involvement. We present the case of an 11-year-old boy with a diagnosis of middle ear T-LBL, which manifested as a headache, hearing loss and peripheral facial paralysis. The child was given intensive chemotherapy and had a complete response. To our knowledge, this is the first case reported in the literature of T-LBL originating in the middle ear. This case aims to help clinicians to be vigilant about the possibility of primary lesions at atypical sites in some special diseases.

Outcome of children and adolescents with lymphoblastic lymphoma

SUMMARY Introduction: lymphoblastic lymphoma (LBL) is the second most common subtype of non-Hodgkin lymphoma in children. The aim of this study was to characterize the clinical course of children and adolescents with LBL treated at a tertiary center. Methods: this is a retrospective cohort study of 27 patients aged 16 years or less with LBL admitted between January 1981 and December 2013. Patients received intensive chemotherapy regimen derived from acute lymphoblastic leukemia (ALL) therapy. Diagnosis was based on biopsy of tumor and/or cytological examination of pleural effusions. The overall survival was analyzed using the Kaplan-Meier method. Results: the median age at diagnosis was 11.6 years (interquartile range, 4.6-13.8). LBL had T cell origin in 16 patients (59%). The most common primary manifestation in T-cell LBL was mediastinum involvement in 9 patients (56%). Intra-abdominal tumor was the major site of involvement in patients with pB-LBL. Most patients had advanced disease (18 patients - 67%) at diagnosis. Twenty-four patients (89%) achieved complete clinical remission. After a median follow-up of 43 months (interquartile range, 6.4-95), 22 patients (81%) were alive in first complete remission. Five children (18.5%) died, three of them soon after admission and two after relapsing. The probability of survival at five years for 20 patients with de novo LBL was 78% (SD 9.4). Conclusion: our findings confirm the favorable prognosis of children with LBL with an intensive chemotherapy regimen derived from ALL therapy.

Antibody therapies for lymphoma in children

BACKGROUND

Lymphomas are the third most common malignancy in childhood. Cure rates are high but have reached a plateau. Therefore new treatment modalities should be developed. Antibody therapy is a successful new treatment option in adult lymphoma. However, none of the therapeutic antibodies available for adults with cancer have been approved for treatment of paediatric lymphoma.

OBJECTIVES

To assess the efficacy of antibody therapy for childhood lymphoma in terms of survival, response and relapse rates, compared with therapy not including antibody treatment. To assess quality of life and the occurrence of adverse effects caused by antibody therapy treatment in children compared with therapy not including antibody treatment.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, 2014, Issue 10), MEDLINE in PubMed (from 1945 to October 2014), EMBASE in EMBASE.com (from 1980 to October 2014) and reference lists of relevant articles. Furthermore, we searched conference proceedings abstracts of SIOP, ASCO and ASH for studies from 2009 to 2013), and the World Health Organization (WHO) ICTRP portal and ClinicalTrials.gov for ongoing trials.

SELECTION CRITERIA

Randomised controlled trials and controlled clinical trials comparing conventional therapy with antibody therapy in children with lymphoma.

DATA COLLECTION AND ANALYSIS

Two authors independently performed the study selection.

MAIN RESULTS

We found no studies meeting the inclusion criteria of the review.

AUTHORS' CONCLUSIONS

At this moment, it is not possible to draw evidence-based conclusions regarding clinical practice. Phase I and II studies show a positive effect of using antibody therapy in childhood lymphoma. Further research is needed to evaluate and implement antibody therapy for paediatric lymphoma.

T-cell Lymphoblastic Lymphoma in the Maxilla and Mandible of a Child: A Rare Case Report

T-cell lymphoblastic lymphomas (T-LBL), defined as neoplasms of immature T cells, are the most common paediatric T-cell lymphoma. These account for approximately 90% of all lymphoblastic lymphomas. The primary manifestation of T-LBL rarely occurs in the oral cavity. In this case report, we describe a case of primary T-LBL affecting the maxilla and mandible of a 10-year-old male patient. This is the first case of T-LBL reported in this region. We emphasize that early diagnosis of aggressive lesions in the maxilla or mandible is one of the responsibilities of oral physicians, who can help patients to overcome the many challenges of malignant diseases.

Disease patterns of pediatric non-Hodgkin lymphoma: A study from a developing area in Egypt

Non-Hodgkin lymphoma (NHL) accounts for 8-10% of all childhood cancers. NHL collectively represents various lymphoid malignancies with diverse clinicopathological and biological characteristics. In this study, we aimed to describe the epidemiological and clinicopathological characteristics and treatment outcomes of pediatric NHL patients treated at the Pediatric Oncology Unit of Zagazig University Hospital and the Benha Specialized Pediatric Hospital. We conducted a cross-sectional retrospective study by reviewing the medical records of 142 patients admitted with a diagnosis of NHL over a period of 8 years (February, 2004 to February, 2012) in these two Oncology Units. The age at presentation ranged between 2 and 15 years, with a mean ± standard deviation (SD) of 6.1±2.8 years and a male:female ratio of 1.7:1. Abdominal involvement was the most common presentation (73.2%). Burkitt's lymphoma (BL) was the most common NHL subtype (69%), followed by lymphoblastic lymphoma, diffuse large B-cell lymphoma and anaplastic large-cell lymphoma, accounting for 18.3, 10.6 and 2.1% of the cases, respectively. The majority of the patients (88.7%) had been diagnosed with advanced disease (Murphy stage III/IV). Complete remission was achieved in 120 cases (84.5%). A total of 16 patients (11.3%) succumbed to the disease during the first few months and 6 patients (4.2%) remained alive following relapse. The mean follow-up duration ± SD was 34.6±25.1 months (range, 3-84 months). The 5-year overall survival (OS) and event-free survival (EFS) rates were 88.7 and 85.1%, respectively. None of the clinical, epidemiological or pathological variables exhibited a statistically significant association with the OS or EFS. In conclusion, NHL occurs at a younger age, with a higher incidence of BL and advanced-stage disease. The outcome of NHL in our two centers was satisfactory, approaching the international rates.

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.

FDG PET/CT in children and adolescents with lymphoma

The aim of this review is to give an overview of FDG PET/CT applications in children and adolescents with lymphoma. Today, FDG PET is used for tailoring treatment intensity in children with Hodgkin lymphoma within the framework of international treatment optimisation protocols. In contrast, the role of this method in children with Non-Hodgkin lymphoma is not well defined. This paper overviews clinical appearance and metabolic behaviour of the most frequent lymphoma subtypes in childhood. The main focus of the review is to summarise knowledge about the role of FDG PET/CT for initial staging and early response assessment.

Agreement between diagnoses of childhood lymphoma assigned in Uganda and by an international reference laboratory

Background

Correct diagnosis is key to appropriate treatment of cancer in children. However, diagnostic challenges are common in low-income and middle-income countries. The objective of the present study was to assess the agreement between a clinical diagnosis of childhood non- Hodgkin lymphoma (NHL) assigned in Uganda, a pathological diagnosis assigned in Uganda, and a pathological diagnosis assigned in The Netherlands.

Methods

The study included children with suspected NHL referred to the Mulago National Referral Hospital, Kampala, Uganda, between 2004 and 2008. A clinical diagnosis was assigned at the Mulago National Referral Hospital, where tissue samples were also obtained. Hematoxylin and eosin-stained slides were used for histological diagnosis in Uganda, and were re-examined in a pathology laboratory in The Netherlands, where additional pathological, virological and serological testing was also carried out. Agreement between diagnostic sites was compared using kappa statistics.

Results

Clinical and pathological diagnoses from Uganda and pathological diagnosis from The Netherlands was available for 118 children. The agreement between clinical and pathological diagnoses of NHL assigned in Uganda was 91% (95% confidence interval [CI] 84–95; kappa 0.84; P < 0.001) and in The Netherlands was 49% (95% CI 40–59; kappa 0.04; P = 0.612). When Burkitt’s lymphoma was considered separately from other NHL, the agreement between clinical diagnoses in Uganda and pathological diagnoses in Uganda was 69% (95% CI 59–77; kappa 0.56; P < 0.0001), and the corresponding agreement between pathological diagnoses assigned in The Netherlands was 32% (95% CI 24–41; kappa 0.05; P = 0.326). The agreement between all pathological diagnoses assigned in Uganda and The Netherlands was 36% (95% CI 28–46; kappa 0.11; P = 0.046).

Conclusion

Clinical diagnosis of NHL in Uganda has a high probability of error compared with pathological diagnosis in Uganda and in The Netherlands. In addition, agreement on the pathological diagnosis of NHL between Uganda and The Netherlands is very low.

Clinical course and prognostic factors of children with Burkitt's lymphoma in a developing country: the experience of a single centre in Brazil

Objective:

Burkitt's lymphoma is the most common subtype of non-Hodgkin lymphoma in children. The aim of this study was to characterize the clinical course and prognostic factors of children and adolescents with Burkitt's lymphoma treated in the Hematology Unit of Hospital das Clínicas, Universidade Federal de Minas Gerais (UFMG).

Methods:

A retrospective cohort study was made of 50 consecutive cases of children and adolescents aged 16 years or less with Burkitt's lymphoma admitted between January 1981 and December 2007. Prognostic factors associated with death were evaluated using the Kaplan-Meier method and compared by the two-tailed log-rank test.

Results:

The median age at diagnosis was 4.7 years. Most patients had abdominal tumors (66.7%) and advanced disease (68.9%) at diagnosis. Thirty-eight patients (84.4%) achieved complete clinical remission and 33 (73.3%) were alive at the first remission. Twelve children (26.7%) died. The median follow-up was 35 months with the probability of overall survival being 73% (89.2% and 35.7% for patients with uric acid < 7 mg/dL and ≥ 7.0 mg/dL, respectively - p-value < 0.001). Uric acid was the only significant prognostic factor at diagnosis.

Conclusion:

Our findings confirm the favorable prognosis of children with Burkitt's lymphoma even when treated with intermediate doses of methotrexate (500 mg/m2). Survival was significantly lower for individuals with concentrations of uric acid > 7 mg/dL.

EBV primary infection in childhood and its relation to B-cell lymphoma development: a mini-review from a developing region

In most underdeveloped countries, the initial contact with Epstein Barr virus (EBV) usually happens in the first decade of life and results in an asymptomatic infection, whereas in developed areas, primary infection in adolescence or adulthood is accompanied by infectious mononucleosis in 50% cases. Although it is generally a harmless passenger, in some individuals, it is associated with B-cell lymphoma. In Argentina, EBV primary infection shows the classical pattern observed in developing populations, given that nearly 70% of patients are seropositive by the age of 2 years. However, EBV association with pediatric Hodgkin and Burkitt lymphoma resembles that observed in developed regions. Concerning diffuse large B-cell lymphoma, our series demonstrated higher EBV association than other adult ones from either developed or underdeveloped countries. Interestingly, the early EBV primary infection observed, characteristic of an underdeveloped population, together with the statistically significant EBV association with patients ≤ 10 years old demonstrated in all types of lymphoma studied, suggest a relationship between low age of EBV seroconversion and B-cell lymphoma development risk.

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.

Leukemia and lymphoma

Leukemia and lymphoma are the most common and third most common pediatric malignancies, respectively, and share cell lineages, but the clinical and imaging manifestations of these malignancies vary substantially. Along with providing pertinent details on classification, epidemiology, and treatment, this article reviews the current roles of imaging in the management of childhood leukemia and lymphoma, with attention to diagnosis, staging, risk stratification, therapy response assessment, and surveillance for disease relapse and adverse effects of therapy. Advances in functional imaging are also discussed to provide insights into future applications of imaging in the management of pediatric patients with leukemia and lymphoma.

Pathologic Evaluation of Routine Pediatric Tonsillectomy Specimens

Objective. Evaluate the utility and explore the cost-effectiveness of mandatory gross or pathologic analysis of routine tonsillectomy specimens in children.

Study Design. Case series with chart review.

Setting. Tertiary care children’s hospital.

Subjects and Methods. Retrospective case series of results of pathologic analysis of tonsillectomy specimens from all pediatric patients who underwent tonsillectomy between 1996 and 2008 (n = 5235). The results of pathologic evaluation of routine and nonroutine specimens were evaluated, and an economic analysis of alternative methods of specimen handling was performed.

Results. Zero cases of unsuspected pathology were identified on planned gross specimen evaluation (n = 4186), resulting in an estimated prevalence of 0 to 0.00088 (95% confidence interval [CI]). Positive pathologic findings on microscopic analysis (n = 1066) were only identified in posttransplant patients (10/63; 95% CI, 0.079-0.27) and cases of surgeon suspicion (8/78; 0.045-0.19). No cases were identified among the 17 undergoing microscopic pathologic analysis on the basis of pathologist suspicion on gross evaluation (95% CI, 0-0.20). From an economic standpoint, microscopic evaluation of routine pediatric tonsillectomy specimens appears to be superior to gross evaluation but with an estimated cost of $766 500 per case of unsuspected lymphoma identified.

Conclusions. This study identifies a very low prevalence of unsuspected pathology on gross pathologic analysis of routine tonsillectomy specimens in children. Exploration of the cost implications suggests that such a practice is not a cost-effective use of limited health care resources. Microscopic examination is appropriate for posttransplantation patients and in cases of surgeon suspicion.

Emerging non-transplant-based strategies in treating pediatric non-Hodgkin's lymphoma

Lymphomas represent the third most common cancer in children and adolescents. The non-Hodgkin's lymphomas comprise a heterogeneous group of tumors, with distinct clinical and pathologic features. Although intensive multi-agent chemotherapy has made non-Hodgkin's lymphoma one of the most curable malignancies in children and young adults, there is room for improvement in treatment, particularly for those with advanced-stage disease and those who relapse after conventional therapy. New approaches are now attempting to reduce the burden of treatment, to focus on novel and more specific biologic targets, and to improve outcomes for patients with advanced-stage disease while reducing the potential for late effects. A comprehensive review of all potential agents is beyond the scope of this review, which will focus on some of the newer strategies for treating non-Hodgkin's lymphoma that are coming into clinical use today.

T-lymphoblastic lymphoma cells express high levels of BCL2, S1P1, and ICAM1, leading to a blockade of tumor cell intravasation

The molecular events underlying the progression of T-lymphoblastic lymphoma (T-LBL) to acute T-lymphoblastic leukemia (T-ALL) remain elusive. In our zebrafish model, concomitant overexpression of bcl-2 with Myc accelerated T-LBL onset while inhibiting progression to T-ALL. The T-LBL cells failed to invade the vasculature and showed evidence of increased homotypic cell-cell adhesion and autophagy. Further analysis using clinical biopsy specimens revealed autophagy and increased levels of BCL2, S1P1, and ICAM1 in human T-LBL compared with T-ALL. Inhibition of S1P1 signaling in T-LBL cells led to decreased homotypic adhesion in vitro and increased tumor cell intravasation in vivo. Thus, blockade of intravasation and hematologic dissemination in T-LBL is due to elevated S1P1 signaling, increased expression of ICAM1, and augmented homotypic cell-cell adhesion.

Pediatric lymphomas in Brazil

OBJECTIVE

This study provides the clinical pathological characteristics of 1301 cases of pediatric/adolescent lymphomas in patients from different geographic regions of Brazil.

METHODS

A retrospective analyses of diagnosed pediatric lymphoma cases in a 10-year period was performed. We believe that it represents the largest series of pediatric lymphomas presented from Brazil.

RESULTS

Non-Hodgkin lymphomas represented 68% of the cases, including those of precursor (36%) and mature (64%) cell origin. Mature cell lymphomas comprised 81% of the B-cell phenotype and 19% of the T-cell phenotype. Hodgkin lymphomas represented 32% of all cases, including 87% of the classical type and 13% of nodular lymphocyte predominant type. The geographic distribution showed 38.4% of the cases in the Southeast region, 28.7% in the Northeast, 16.1% in the South, 8.8% in the North, and 8% in the Central-west region. The distribution by age groups was 15-18 years old, 33%; 11-14 years old, 26%; 6-10 years old, 24%; and 6 years old or younger, 17%. Among mature B-cell lymphomas, most of the cases were Burkitt lymphomas (65%), followed by diffuse large B-cell lymphomas (24%). In the mature T-cell group, anaplastic large cell lymphoma, ALK-positive was the most prevalent (57%), followed by peripheral T-cell lymphoma, then not otherwise specified (25%). In the group of classic Hodgkin lymphomas, the main histological subtype was nodular sclerosis (76%). Nodular lymphocyte predominance occurred more frequently than in other series.

CONCLUSION

Some of the results found in this study may reflect the heterogeneous socioeconomical status and environmental factors of the Brazilian population in different regions.

Trends in survival after diagnosis with hematologic malignancy in adolescence or young adulthood in the United States, 1981-2005

BACKGROUND

: There are few population-based studies of long-term survival of adolescents and young adults with hematologic malignancies; most pertain to patients diagnosed in the 1990s or earlier. Period analysis was used to obtain up-to-date information on survival expectations of adolescents and young adults diagnosed with hematologic malignancies through the early 21st century.

METHODS

: Period analysis was used to calculate 5- and 10-year relative survival for adolescents and young adults diagnosed with Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL), acute lymphoblastic leukemia (ALL), acute myeloblastic leukemia (AML), and chronic myelocytic leukemia (CML) for 5 5-year periods from 1981-1985 to 2001-2005, using data from the Surveillance, Epidemiology, and End Results database.

RESULTS

: Survival strongly improved for each of the 5 hematologic malignancies. Increases in 10-year relative survival between 1981-1985 and 2001-2005 were as follows: HL, from 80.4% to 93.4%; NHL, from 55.6% to 76.2%; ALL, from 30.5% to 52.1%; AML, from 15.2% to 45.1%; CML, from 0 to 74.5% (P < .001 in all cases). However, although survival improved steadily throughout the period examined for the lymphomas and CML, survival was stable during the late 1990s and early 21st century for the acute leukemias.

CONCLUSIONS

: Survival expectations for adolescents and young adults with hematologic malignancies have strongly improved since the 1980s. However, with the exception of HL, survival rates have not reached the levels observed for children diagnosed with these malignancies, and survival expectations for patients with acute leukemia have stabilized at relatively low levels. Cancer 2009. (c) 2009 American Cancer Society.

Minimal disseminated disease in childhood T-cell lymphoblastic lymphoma: a report from the children's oncology group

PURPOSE Disease dissemination to the bone marrow is detected at diagnosis in approximately 15% of children with T-cell lymphoblastic lymphoma (T-LL). It is unclear whether the remaining patients have submicroscopic systemic disease and, if so, what is the clinical significance of this finding. PATIENTS AND METHODS Using a flow cytometric method that can detect one T-LL cell among 10,000 normal cells, we examined bone marrow and peripheral-blood samples collected from 99 children with T-LL at diagnosis, as well as blood samples collected from 42 patients during treatment. Results In 71 (71.7%) of the 99 marrow samples obtained at diagnosis, T-LL cells represented 0.01% to 31.6% (median, 0.22%) of mononuclear cells; 57 of the 71 T-LL-positive samples were from patients with stage II/III disease. Results of studies in bilateral marrow aspirates were highly concordant. Two-year event-free survival (EFS) was 68.1% +/- 11.1% (SE) for patients with > or = 1% T-LL cells in bone marrow versus 90.7% +/- 4.4% for those with lower levels of marrow involvement (P = .031); EFS for patients with > or = 5% lymphoblasts was 51.9% +/- 18.0% (P = .009). T-LL cells were as prevalent in blood as in marrow; monitoring residual T-LL cells in blood during remission induction therapy identified patients with slower disease clearance. CONCLUSION More than two thirds of children with T-LL have disseminated disease at diagnosis, a proportion much higher than previously demonstrated. Measurements of disease dissemination at diagnosis might provide useful prognostic information, which can be further refined by monitoring response to therapy through blood testing.

Successful salvage chemotherapy for isolated central nervous system (CNS) relapse in Burkitt lymphoma: monocentric experience of 3 pediatric patients

Short-term intensive chemotherapy regimens have substantially improved the prognosis of pediatric patients with Burkitt lymphoma (BL), which now has an excellent overall outcome. However, central nervous system (CNS) involvement at diagnosis remains a poor prognostic factor, and progressive or relapsed disease in the CNS is associated with even worse outcomes. We report 3 boys aged 4, 7, and 12 years treated under the French Société Française d'Oncologie Pédiatrique LMB 89/96 protocols who presented, respectively, with CNS-/bone marrow+ stage-IV BL; CNS+ stage-IV BL; and stage-I BL. Each experienced an isolated CNS relapse, which was treated with CNS-directed salvage chemotherapy. All 3 are alive after 11 years of median follow-up, indicating that this chemotherapy regimen can be curative in pediatric BL with isolated CNS relapse.

Characterization of childhood precursor T-lymphoblastic lymphoma by immunophenotyping and fluorescent in situ hybridization: a report from the Children's Oncology Group

BACKGROUND

T-lymphoblastic lymphoma (T-LBL) accounts for 25-30% of childhood non-Hodgkin's lymphoma and is closely related to T-lymphoblastic leukemia (T-ALL). Recently, we demonstrated distinct differences in gene expression between childhood T-LBL and T-ALL, but molecular pathogenesis and relevant protein expression patterns in T-LBL remain poorly understood.

PROCEDURE

Children with T-LBL with disseminated disease were registered and treated on COG protocol 5971. Paraffin-embedded tumor tissue was obtained at diagnosis for immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) studies. We determined the pattern and intensity of staining for c-Myc, Skp2, Mib-1, p53, TCL-1, bcl-2, and bcl-6 proteins by IHC and c-Myc, p53, bcl-2, bcl-6, and TCR alpha/delta molecular alterations by FISH in 22 pediatric T-LBL cases.

RESULTS

The majority of T-LBL samples expressed Mib-1 (59%) and c-Myc (77%) proteins in greater than 50% of the cells, but Skp2 (14%), p53 (14%), and bcl-2 (23%) expression was less common. FISH studies demonstrated 18% gains and 10% losses in c-Myc, 16% gains in p53, 12% gains and 6% losses in bcl-2, and 6% gains and 19% losses in bcl-6 with little direct correlation between the IHC and FISH studies.

CONCLUSIONS

Childhood T-LBL is a highly proliferative tumor associated with enhanced expression of c-Myc protein, but without detectable c-Myc molecular alterations. FISH studies did not identify consistent etiologies of molecular dysregulation, and future studies with other molecular approaches may be required to elucidate the molecular pathogenesis of childhood T-LBL.

Shortened intensified multi-agent chemotherapy and non-cross resistant maintenance therapy for advanced lymphoblastic lymphoma in children and adolescents: report from the Children's Oncology Group

Pediatric lymphoblastic lymphoma (LL) has utilized treatment strategies similar to childhood acute lymphoblastic leukaemia (ALL) with prolonged maintenance chemotherapy. We report the results of a pilot study to estimate the feasibility, toxicity and efficacy of a 12-month aggressive multi-agent chemotherapy regimen in children and adolescents with advanced LL. Between July 1994 and June 1997, 85 eligible children and adolescents with advanced LL (Stage III/IV) were enrolled on this pilot study. Patients achieving a complete response following induction and consolidation received six cycles of maintenance chemotherapy for a total duration of 12 months. Grade III/IV toxicities included: hematological (80%), infections (20%), stomatitis and elevated transaminases, (29%). There were a total of 19 events, 13 relapses, two secondary acute myeloid leukaemia and four toxic deaths (5%). The 5-year event-free survival (EFS) and overall survival (OS) was 78 +/- 4.5% and 85 +/- 3.9%, respectively. Relapsed patients had a 5-year OS of only 33 +/- 14%. Multivariate analysis failed to demonstrate age, gender, lactate dehydrogenase level, presence of marrow and/or central nervous system disease to have independent prognostic value. These results suggest that this experimental approach is safe and results in similar outcomes as more prolonged childhood ALL regimens.

Non-anaplastic peripheral t-cell lymphoma in childhood and adolescence: a Children's Oncology Group study

BACKGROUND

Peripheral T-cell lymphomas (PTCL) other than anaplastic large cell lymphoma (ALCL) are rare in young patients. While a high proportion of adults with PTCL have poor risk disease, pediatric PTCL is not well characterized. This study examines the outcome of localized and advanced PTCL in pediatric patients treated in standardized fashion.

PROCEDURE

We identified 20 pediatric patients diagnosed with PTCL whose tumor cells did not express CD30 and/or ALK, as determined by immunohistochemistry, between 1992 and 2000 on one of two treatment protocols for localized NHL (POG 9219) or advanced stage large cell lymphoma (POG 9315). All cases were centrally reviewed.

RESULTS

The median age was 12.6 (range 0.7-16.9)-9 male and 11 female. Histological subtypes in the WHO Classification included PTCL, unspecified (12), extra-nodal NK/T-cell lymphoma of nasal type (4), subcutaneous panniculitis-like T cell lymphoma (1) and enteropathy-type T-cell lymphoma (1). Two cases exhibited both T-cell and histiocyte markers and were reclassified as histiocytic sarcoma per the WHO, although T-lineage remains possible. Of 10 patients with localized disease, only two relapsed and 9 survive. Of 10 patients with advanced disease, six relapsed and five (50%) survive.

CONCLUSIONS

These results suggest that localized PTCL in children and adolescents is frequently cured with modern therapy, but that advanced stage cases may require novel therapy.

Excellent survival following two courses of COPAD chemotherapy in children and adolescents with resected localized B-cell non-Hodgkin's lymphoma: results of the FAB/LMB 96 international study

High cure rates are possible in children with localized mature B-cell lymphoma (B NHL) using a variety of chemotherapeutic strategies. To reduce late sequelae, the duration and intensity of chemotherapy has been progressively reduced. The Lymphome Malins de Burkitt (LMB) 89 study reported long-term survival in almost all children with localized resected disease treated with two courses of COPAD (cyclophosphamide, vincristine, prednisolone and doxorubicin). This study was designed to confirm the effectiveness of this approach in a larger number of patients in a multinational co-operative study. The patient cohort was part of an international study (French-American-British LMB 96), which included all disease stages and involved three national groups. Patients in this part of the study had resected stage I or completely resected abdominal stage II disease. Following surgery, two courses of COPAD were given, without intrathecal (IT) chemotherapy. One hundred and thirty-two children were evaluable. Two of 264 (0.9%) courses were associated with grade IV toxicity (one stomatitis and one infection). With a median follow up of 50.5 months, the 4 year event-free survival is 98.3% and overall survival is 99.2%. Children with resected localized B-NHL can be cured with minimal toxicity following two courses of low intensity treatment without IT chemotherapy.

A unique case of adolescent CD56-negative extranodal NK/T-cell lymphoma, nasal type

Mature T-cell neoplasms are unusual in the pediatric population. The majority of these neoplasms in the United States are anaplastic large cell lymphomas (ALCL) characterized by CD30 and anaplastic lymphoma kinase-1 expression. Extranodal natural killer/T (NK/T)-cell lymphomas, nasal type, are extremely rare. Extranodal NK/T-cell lymphomas often express CD56, are associated with Epstein-Barr virus, and are negative for CD30. Clinically, extranodal NK/T-cell lymphomas are much more aggressive than ALCL, and require different treatment strategies. The authors present an adolescent male with a CD56 negative extranodal NK/T-cell lymphoma, nasal type. The lymphoma was partially positive for CD30, diffusely positive for EBV by in situ hybridization, and clonal for T-cell receptor gene rearrangement and cytogenetic abnormalities. The patient was aggressively treated with chemotherapy, surgery, and radiation. More than 2 years from completion of the therapy, the patient remains disease free. This case highlights the importance and difficulty of accurate identification of this type of rare tumor. We further present the literature review and discuss the diagnostic criteria for extranodal NK/T lymphoma using morphologic, immunologic, molecular, and cytogenetic information.

Stem cell transplantation for pediatric lymphoma: past, present and future

Lymphoma is the third most common cancer in children < or =15 years of age. The prognosis for children with newly diagnosed chemosensitive non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD) has improved significantly. However, in children with relapsed and refractory NHL, the prognosis is not as promising and the best treatment approach for this poor risk group continues to be a challenge. Between 25 and 30% of patients with advanced stage HD still relapse and in subsets of this group, the outcome is dismal. Aggressive chemotherapy followed by autologous bone marrow transplantation has been used with some improvement in survival. Some centers have investigated allogeneic stem cell transplantation in pediatric patients with recurrent/relapsed lymphoma. There is little consistency in therapeutic approaches and there is no formal recommendation on the best approach for this poor prognostic subgroup. We illustrate the reported pediatric experience of transplantation for lymphoma and discuss how the results from these trials are influencing how we approach the treatment in certain subgroups of pediatric patients with relapsed/refractory lymphoma.

Diffuse large B-cell lymphoma in the young in Japan: a study by the Osaka Lymphoma Study Group

Clinicopathological and immunophenotypical characteristics in 24 patients with diffuse large B-cell lymphoma (DLBCL) under 30 years of age in Osaka, Japan were examined, and the results compared to those of DLBCL patients aged over 40 years in Osaka and of young DLBCL patients in Western countries. The level of LDH and IPI score at initial diagnosis were significantly lower in young than older patients. The sex ratio (M:F) and age range (median) in the young and older groups were 1.18 and 11-30 (24.8) years and 1.59 and 42-87 (62.4) years, respectively. Extranodal presentation was higher in the young group (83.3% versus 60.0%, P < 0.05). Based on immunophenotyping with anti-CD10, bcl-6, and MUM1 antibodies, the cases were categorized as germinal center B-cell (GCB) (CD10+ or CD10-, bcl-6+, MUM1+) or non-GCB phenotype. The frequency of GCB type was significantly lower in the young group than older group (25% vs. 54%, P < 0.05), and much lower than that reported for young patients in Western countries. In situ hybridization revealed one of the young patients to be positive for Epstein-Barr virus (EBV). In the older group, none of 31 cases showed EBV positivity. Three year event-free and overall survival rates of young patients were better than those of the older patients, although not significantly different. DLBCL in the young in Japan is characterized by a much lower frequency of the GCB phenotype compared to that in Western countries.

Recommended curriculum for teaching hematopathology to subspecialty hematopathology fellows

The performance and interpretation of clinical hematology and hematopathology laboratory tests and diagnosis of benign or malignant hematolymphoid disorders present unique challenges to hematopathology fellow trainees. To assist hematopathology fellowship program directors in preparing trainees to meet these challenges, a task force of pathologists with expertise in hematopathology developed a suggested training curriculum that includes a comprehensive list of topics in the areas of analytic hematology, bone marrow pathology, lymph node pathology, splenic pathology, lymphoma diagnostics, cytogenetics, and molecular diagnostics. This report also includes recommendations for training experiences that will facilitate the transition of subspecialty residents to practicing consultants in hematopathology.

Results of a randomized international study of high-risk central nervous system B non-Hodgkin lymphoma and B acute lymphoblastic leukemia in children and adolescents

The prognosis for higher risk childhood B-cell non-Hodgkin lymphoma has improved over the past 20 years but the optimal intensity of treatment has yet to be determined. Children 21 years old or younger with newly diagnosed B-cell non-Hodgkin lymphoma/B-cell acute lymphoblastic leukemia (B-NHL/B-ALL) with higher risk factors (bone marrow [BM] with or without CNS involvement) were randomized to standard intensity French-American-British/Lymphoma Malignancy B (FAB/LMB) therapy or reduced intensity (reduced cytarabine plus etoposide and deletion of 3 maintenance courses M2, M3, M4). All patients with CNS disease had additional high-dose methotrexate (8 g/m2) plus extra intrathecal therapy. Fifty-one percent had BM involvement, 20% had CNS involvement, and 29% had BM and CNS involvement. One hundred ninety patients were randomized. The probabilities of 4-year event-free survival (EFS) and survival (S) were 79% +/- 2.7% and 82% +/- 2.6%, respectively. In patients in remission after 3 cycles who were randomized to standard versus reduced-intensity therapy, the 4-year EFS after randomization was 90% +/- 3.1% versus 80% +/- 4.2% (one-sided P = .064) and S was 93% +/- 2.7% versus 83% +/- 4.0% (one-sided P = .032). Patients with either combined BM/CNS disease at diagnosis or poor response to cyclophosphamide, Oncovin [vincristine], prednisone (COP) reduction therapy had a significantly inferior EFS and S (P < .001). Standard-intensity FAB/LMB therapy is recommended for children with high-risk B-NHL (B-ALL with or without CNS involvement).

Chromosome abnormalities in advanced stage lymphoblastic lymphoma of children and adolescents: a report from CCG-E08

Among pediatric non-Hodgkin lymphomas, one of the most frequent types is lymphoblastic lymphoma (LBL). Specific chromosome abnormalities are associated with prognosis in childhood acute lymphoblastic leukemia, but have not been evaluated for prognostic value in pediatric LBL. For the Children's Cancer Group protocol CCG-E-08 Etiologic Study of Non-Hodgkin Lymphoma in Childhood, 13 patients were enrolled with cytogenetic analysis of LBL and on treatment protocol CCG-502. Pathology material and karyotypes at initial diagnosis were given central review. The patients were aged 6-13 years (median 9 years), with a male-to-female ratio of 12:1. All patients had advanced disease. Disease relapsed in six patients (event-free survival 54% +/- 14%, median 10.8 years). Chromosome abnormalities were identified in 11 (85%), and translocations at 14q11.2 likely involving the T-cell receptor alpha/delta locus (TCR A/D) occurred in 4 (31%). For patients with relapse, four had translocations t(1;14)(p32;q11.2), t(8;14)(q24.1;q11.2), t(11;14)(p13;q11.2), or t(9;17)(q34;q23), involving breakpoints in the regions of TAL1, MYC, LMO2, and NOTCH1, respectively. Pediatric advanced LBLs have a high frequency of chromosome abnormalities; in this limited study, these often involved translocations at 14q11.2, the site of TCR A/D. Translocations possibly involving TAL1, MYC, LMO2, or NOTCH1 may have contributed to poor outcome. Further studies are warranted in larger cohorts of children and adolescents with LBL to evaluate the prognostic significance.

Non-Hodgkin's lymphoma in children and adolescents

Lymphoma is the third most common cancer in children and adolescents. Non-Hodgkin's lymphomas comprise a heterogeneous group of tumors with distinct pathologic and clinical characteristics. Over the past three decades, significant advancements have been made in the molecular characterization of these disorders. With the use of intensive multiagent chemotherapy, non-Hodgkin's lymphomas are now among the most successfully treated cancers in the pediatric population. Future goals of therapy include reduction of treatment duration for early-stage patients and identification of novel targets and therapeutics for advanced-stage patients.