Contribution of the Epstein-Barr virus to the oncogenesis of mature T-cell lymphoproliferative neoplasms.

EBV is a lymphotropic virus, member of the Herpesviridae family that asymptomatically infects more than 90% of the human population, establishing a latent infection in memory B cells. EBV exhibits complex survival and persistence dynamics, replicating its genome through the proliferation of infected B cells or production of the lytic virions. Many studies have documented the infection of T/NK cells by EBV in healthy individuals during and after primary infection. This feature has been confirmed in humanized mouse models. Together these results have challenged the hypothesis that the infection of T/NK cells per se by EBV could be a triggering event for lymphomagenesis. Extranodal NK/T-cell lymphoma (ENKTCL) and Epstein-Barr virus (EBV)-positive nodal T- and NK-cell lymphoma (NKTCL) are two EBV-associated lymphomas of T/NK cells. These two lymphomas display different clinical, histological and molecular features. However, they share two intriguing characteristics: the association with EBV and a geographical prevalence in East Asia and Latin America. In this review we will discuss the genetic characteristics of EBV in order to understand the possible role of this virus in the oncogenesis of ENKTCL and NKTCL. In addition, the main immunohistological, molecular, cytogenetic and epigenetic differences between ENKTCL and NKTCL will be discussed, as well as EBV differences in latency patterns and other viral molecular characteristics.

Tumor-associated macrophages in classical Hodgkin lymphoma: hormetic relationship to outcome.

Commonly attributed to the prevalence of M2 macrophages, tumor-associated macrophages (TAM) are linked to poor outcome in Hodgkin lymphoma (HL). MYC is supposed to control the expression of M2-specific genes in macrophages, and deficiency in MYC-positive macrophages inhibits tumor growth in mouse models. To verify this hypothesis for HL, seventy-six samples were subjected to immunohistochemical double staining using CD68 or CD163 macrophage-specific antibodies and a reagent detecting MYC. For each cell population, labelled cells were grouped according to low, intermediate and high numbers and related to disease-free survival (DFS) and overall survival (OS). MYC+ cells accounted for 21% and 18% of CD68+ and CD163+ cells, respectively. Numbers of MYC- macrophages were significantly higher in EBV+ cases while no differences were observed for MYC+ macrophages between EBV+ and EBV- cases. Cases with highest numbers of macrophages usually showed worst DFS and OS. In most scenarios, intermediate numbers of macrophages were associated with better outcome than very low or very high numbers. Our observations are reminiscent of the "hormesis hypothesis" and suggest that a relative lack of TAM may allow HL growth while macrophages display an inhibitory effect with increasing numbers. Above a certain threshold, TAM may again support tumor growth.

Revisiting the Tissue Microenvironment of Infectious Mononucleosis: Identification of EBV Infection in T Cells and Deep Characterization of Immune Profiles.

To aid understanding of primary EBV infection, we have performed an in depth analysis of EBV-infected cells and of local immune cells in tonsils from infectious mononucleosis (IM) patients. We show that EBV is present in approximately 50% of B-cells showing heterogeneous patterns of latent viral gene expression probably reflecting different stages of infection. While the vast majority of EBV+ cells are B-cells, around 9% express T-cell antigens, with a predominance of CD8+ over CD4+ cells. PD-L1 was expressed by a median of 14% of EBV+ cells. The numbers of EBER+PD-L1+ cells were directly correlated with the numbers of EBER+CD3+ and EBER+CD8+ cells suggesting a possible role for PD-L1 in EBV infection of T-cells. The microenvironment of IM tonsils was characterized by a predominance of M1-polarized macrophages over M2-polarized cells. However, at the T-cell level, a heterogeneous picture emerged with numerous Th1/cytotoxic cells accompanied and sometimes outnumbered by Th2/regulatory T-cells. Further, we observed a direct correlation between the numbers of Th2-like cells and EBV- B-cells. Also, a prevalence of cytotoxic T-cells over Th2-like cells was associated with an increased viral load. These observations point to contribution of B- and Th2-like cells to the control of primary EBV infection. 35% of CD8+ cells were differentiated CD8+TBET+ cells, frequently detected in post-capillary venules. An inverse correlation was observed between the numbers of CD8+TBET+ cells and viral load suggesting a pivotal role for these cells in the control of primary EBV infection. Our results provide the basis for a better understanding of immune reactions in EBV-associated tumors.

Pathway-focused gene expression profiles and immunohistochemistry detection identify contrasting association of caspase 3 (CASP3) expression with prognosis in pediatric classical Hodgkin lymphoma.

The search for clinically relevant molecular markers in classical Hodgkin lymphoma (cHL) is hampered by the histopathological complexity of the disease, resulting from the admixture of a small number of neoplastic Hodgkin and Reed-Sternberg (H-RS) cells with an abundant and heterogeneous microenvironment. In this study, we evaluated gene expression profiles of 11 selected genes previously proposed as a molecular score for adult cHL, aiming to validate its application in the pediatric setting. Assays were performed by RT-qPCR from formalin-fixed paraffin-embedded (FFPE) lymph nodes in 80 patients with cHL. Selected genes were associated with cell cycle (CENPF, CDK1, CCNA2, CCNE2, and HMMR), apoptosis (BCL2, BCL2L1, and CASP3), and monocytes/macrophages (LYZ and STAT1). Despite using controlled preanalytical and analytical strategies, we were not able to validate the 11-gene score to be applied in pediatric cHL. Principal component analysis (PCA) disclosed 3 components that accounted for 65.7% of the total variability. The second PC included microenvironment and apoptosis genes, from which CASP3 expression was associated with a short time of progression-free survival, which impact was maintained in the unfavorable risk group, Epstein-Barr virus-negative cases, and multivariate analysis (P < .05). Because this is a counterintuitive association, CASP3 active expression was assessed at the protein level in H-RS cells by double immunohistochemistry. In contrast to the association of mRNA levels with a poor therapeutic response, a high number of cleaved CASP3+ cells were associated with longer progression-free survival (P = .03) and overall survival (P = .002). Our results demonstrate the feasibility of using FFPE samples as RNA source for molecular prognostication, but argue against the concept of direct and wide applicability of molecular scores in cHL. We reinforce the potential of CASP3 as an interesting target to be explored in adult and pediatric cHL, and alert for its dual biological role in H-RS cells and tumor microenvironment.

Interleukin 10 (IL10) proximal promoter polymorphisms beyond clinical response in classical Hodgkin lymphoma: Exploring the basis for the genetic control of the tumor microenvironment.

Interleukin-10 (IL10) is an immune regulatory cytokine. Single nucleotide polymorphisms (SNPs) in IL10 promoter have been associated with prognosis in adult classical Hodgkin lymphoma (cHL). We analyzed IL10 SNPs -1082 and -592 in respect of therapy response, gene expression and tumor microenvironment (TME) composition in 98 pediatric patients with cHL. As confirmatory results, we found that -1082AA/AG; -592CC genotypes and ATA haplotype were associated with unfavourable prognosis: Progression-free survival (PFS) was shorter in -1082AA+AG (72.2%) than in GG patients (100%) (P = 0.024), and in -592AA (50%) and AC (74.2%) vs. CC patients (87.0%) (P = 0.009). In multivariate analysis, the -592CC genotype and the ATA haplotype retained prognostic impact (HR: 0.41, 95% CI 0.2-0.86; P = 0.018, and HR: 3.06 95% CI 1.03-9.12; P = 0.044, respectively). Our analysis further led to some new observations, namely: (1) Low IL10 mRNA expression was associated with -1082GG genotype (P = 0.014); (2) IL10 promoter polymorphisms influence TME composition;-1082GG/-592CC carriers showed low numbers of infiltrating cells expressing MAF transcription factor (20 vs. 78 and 49 vs. 108 cells/mm2, respectively; P< 0.05); while ATA haplotype (high expression) associated with high numbers of MAF+ cells (P = 0.005). Specifically, -1082GG patients exhibited low percentages of CD68+MAF+ (M2-like) intratumoral macrophages (15.04% vs. 47.26%, P = 0.017). Considering ours as an independent validation cohort, our results give support to the clinical importance of IL10 polymorphisms in the full spectrum of cHL, and advance the concept of genetic control of microenvironment composition as a basis for susceptibility and therapeutic response.

Persistent KSHV Infection Increases EBV-Associated Tumor Formation In Vivo via Enhanced EBV Lytic Gene Expression.

The human tumor viruses Epstein-Barr virus (EBV) and Kaposi sarcoma-associated herpesvirus (KSHV) establish persistent infections in B cells. KSHV is linked to primary effusion lymphoma (PEL), and 90% of PELs also contain EBV. Studies on persistent KSHV infection in vivo and the role of EBV co-infection in PEL development have been hampered by the absence of small animal models. We developed mice reconstituted with human immune system components as a model for KSHV infection and find that EBV/KSHV dual infection enhanced KSHV persistence and tumorigenesis. Dual-infected cells displayed a plasma cell-like gene expression pattern similar to PELs. KSHV persisted in EBV-transformed B cells and was associated with lytic EBV gene expression, resulting in increased tumor formation. Evidence of elevated lytic EBV replication was also found in EBV/KSHV dually infected lymphoproliferative disorders in humans. Our data suggest that KSHV augments EBV-associated tumorigenesis via stimulation of lytic EBV replication.

Prevalence of HPV infection in head and neck carcinomas shows geographical variability: a comparative study from Brazil and Germany.

Rising prevalence rates of high-risk human papillomaviruses (hrHPV) infection in oropharyngeal carcinoma (up to 80 %) have been reported in North America and Scandinavia. We have analysed 424 German and 163 Brazilian head and neck squamous cell carcinomas (HNSCC) from the oral cavity (OSCC), oropharynx (OPSCC) and hypopharynx (HPSCC) using p16 immunohistochemistry, HPV DNA PCR and sequencing, hrHPV DNA in situ hybridisation (ISH) and hrHPV E6/E7 RNA ISH. In the German series, 52/424 cases (12.3 %) were p16-positive/hrHPV-positive (OSCC 3.8 % [10/265], OPSCC 34.4 % [42/122], HPSCC 0 % [0/37]). In addition, there were 9 cases that were p16-positive/hrHPV-negative (5 OPSCC and 4 OSCC). In the Brazilian series, the overall hrHPV DNA prevalence by PCR was 11.0 % ([18/163]; OSCC 6 % [5/83], OPSCC 15.5 % [11/71], HPSCC 22.2 % [2/9]). Ten of these cases were hrHPV-positive/p16-positive. The remaining 8 hrHPV-positive/p16-negative cases were also negative in both ISH assays. Furthermore, 5 p16-positive/hrHPV-negative cases (2 OPSCC and 3 OSCC) were identified. In both series, HPV16 was by far the most common HPV type detected. We confirm that regardless of geographical origin, the highest hrHPV prevalence in HNSCC is observed in oropharyngeal carcinomas. The proportion of HPV-associated OPSCC was substantially higher in the German cohort than in the Brazilian series (34.4 vs. 15.5 %), and in both groups, the prevalence of hrHPV in OPSCC was much lower than in recent reports from North America and Scandinavia. We suggest, therefore, that it may be possible to define areas with high (e.g. USA, Canada, Scandinavia), intermediate (e.g. Germany) and low (e.g. Brazil) prevalences of HPV infection in OPSCC.

Analysis of biological and technical variability in gene expression assays from formalin-fixed paraffin-embedded classical Hodgkin lymphomas.

Formalin-fixed paraffin-embedded (FFPE) tissues are invaluable sources of biological material for research and diagnostic purposes. In this study, we aimed to identify biological and technical variability in RT-qPCR TaqMan® assays performed with FFPE-RNA from lymph nodes of classical Hodgkin lymphoma samples. An ANOVA-nested 6-level design was employed to evaluate BCL2, CASP3, IRF4, LYZ and STAT1 gene expression. The most variable genes were CASP3 (low expression) and LYZ (high expression). Total variability decreased after normalization for all genes, except by LYZ. Genes with moderate and low expression were identified and suffered more the effects of the technical manipulation than high-expression genes. Pre-amplification was shown to introduce significant technical variability, which was partially alleviated by lowering to a half the amount of input RNA. Ct and Cy0 quantification methods, based on cycle-threshold and the kinetic of amplification curves, respectively, were compared. Cy0 method resulted in higher quantification values, leading to the decrease of total variability in CASP3 and LYZ genes. The mean individual noise was 0.45 (0.31 to 0.61 SD), indicating a variation of gene expression over ~1.5 folds from one case to another. We showed that total variability in RT-qPCR from FFPE-RNA is not higher than that reported for fresh complex tissues, and identified gene-, and expression level-sources of biological and technical variability, which can allow better strategies for designing RT-qPCR assays from highly degraded and inhibited samples.

Human natural killer cells prevent infectious mononucleosis features by targeting lytic Epstein-Barr virus infection.

Primary infection with the human oncogenic Epstein-Barr virus (EBV) can result in infectious mononucleosis (IM), a self-limiting disease caused by massive lymphocyte expansion that predisposes for the development of distinct EBV-associated lymphomas. Why some individuals experience this symptomatic primary EBV infection, whereas the majority acquires the virus asymptomatically, remains unclear. Using a mouse model with reconstituted human immune system components, we show that depletion of human natural killer (NK) cells enhances IM symptoms and promotes EBV-associated tumorigenesis mainly because of a loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies.

Macrophage polarisation: an immunohistochemical approach for identifying M1 and M2 macrophages.

Macrophage polarization is increasingly recognised as an important pathogenetic factor in inflammatory and neoplastic diseases. Proinflammatory M1 macrophages promote T helper (Th) 1 responses and show tumoricidal activity. M2 macrophages contribute to tissue repair and promote Th2 responses. CD68 and CD163 are used to identify macrophages in tissue sections. However, characterisation of polarised macrophages in situ has remained difficult. Macrophage polarisation is regulated by transcription factors, pSTAT1 and RBP-J for M1, and CMAF for M2. We reasoned that double-labelling immunohistochemistry for the detection of macrophage markers together with transcription factors may be suitable to characterise macrophage polarisation in situ. To test this hypothesis, we have studied conditions associated with Th1- and Th2-predominant immune responses: infectious mononucleosis and Crohn's disease for Th1 and allergic nasal polyps, oxyuriasis, wound healing and foreign body granulomas for predominant Th2 response. In all situations, CD163+ cells usually outnumbered CD68+ cells. Moreover, CD163+ cells, usually considered as M2 macrophages, co-expressing pSTAT1 and RBP-J were found in all conditions examined. The numbers of putative M1 macrophages were higher in Th1- than in Th2-associated diseases, while more M2 macrophages were seen in Th2- than in Th1 related disorders. In most Th1-related diseases, the balance of M1 over M2 cells was shifted towards M1 cells, while the reverse was observed for Th2-related conditions. Hierarchical cluster analysis revealed two distinct clusters: cluster I included Th1 diseases together with cases with high numbers of CD163+pSTAT1+, CD68+pSTAT1+, CD163+RBP-J+ and CD68+RBP-J+ macrophages; cluster II comprised Th2 conditions together with cases displaying high numbers of CD163+CMAF+ and CD68+CMAF+ macrophages. These results suggest that the detection of pSTAT1, RBP-J, and CMAF in the context of CD68 or CD163 expression is a suitable tool for the characterisation of macrophage polarisation in situ. Furthermore, CD163 cannot be considered a reliable M2 marker when used on its own.

Detection of HPV infection in head and neck squamous cell carcinoma: a practical proposal.

Detecting human papillomavirus (HPV) infection in head and neck squamous cell carcinoma (HNSCC) is clinically relevant, but there is no agreement about the most appropriate methodology. We have studied 64 oropharyngeal carcinomas using p16 immunohistochemistry, HPV DNA in situ hybridisation (ISH) and HPV DNA polymerase chain reaction (PCR) followed by pyrosequencing. We have also evaluated a new assay, RNAscope, designed to detect HPV E6/E7 RNA transcripts. Using a threshold of 70 % labelled tumour cells, 21 cases (32.8 %) were p16 positive. Of these, 19 cases scored positive with at least one HPV detection assay. Sixteen cases were positive by HPV DNA-ISH, and 18 cases were positive using the E6/E7 RNAscope assay. By PCR and pyrosequencing, HPV16 was detected in 15 cases, while one case each harboured HPV33, 35 and 56. All p16-negative cases were negative using these assays. We conclude that p16 expression is a useful surrogate marker for HPV infection in HNSCC with a high negative predictive value and that p16-positive cases should be further evaluated for HPV infection, preferably by PCR followed by type determination. Using RNase digestion experiments, we show that the RNAscope assay is not suitable for the reliable discrimination between E6/E7 RNA transcripts and viral DNA.

Tumor-associated macrophages in pediatric classical Hodgkin lymphoma: association with Epstein-Barr virus, lymphocyte subsets, and prognostic impact.

PURPOSE: Tumor-infiltrating macrophages are associated with adverse outcome in adult classical Hodgkin lymphoma (cHL). We have previously shown age-related changes in the lymphocyte composition of pediatric cHL. We therefore hypothesized that the number, function, and prognostic impact of macrophages in pediatric cHL would be different from adult cases. EXPERIMENTAL DESIGN: We analyzed the number of macrophages and dendritic cells (DC) in the tumor microenvironment of pediatric cHL by immunohistochemistry. Results were analyzed in context of age, histologic characteristics, Epstein-Barr virus (EBV) status, clinical follow-up, and our previous study of T-cell populations in these cases. RESULTS: One hundred cHL cases were studied, including 69% nodular sclerosis and 23% mixed cellularity cases. A total of 44.8% of cases were EBV-positive. Patients ≤10 years displayed more CD14(+) cells (P = 0.025). In comparison with nodular sclerosis, mixed cellularity was characterized by higher numbers of CD14(+), (P = 0.003) and CD163(+) cells (P = 0.027). EBV(+) cases exhibited higher numbers of CD14(+) (P < 0.0005), CD68(+) (P = 0.005), and CD163(+) cells (P = 0.02). CD68-positive cells did not display an effect on outcome. Worse overall survival was observed in cases with CD163/CD8 ratio ≥2 (P = 0.007). High numbers of CD163(+) cells were associated with worse progression-free survival (PFS; P = 0.015). Furthermore, high numbers of CD163(+) and granzyme B(+) cells were associated with worse PFS in EBV-negative (P = 0.005) but not in EBV-positive cases. CONCLUSION: Our results suggest that macrophage composition in pediatric cHL is distinct from adults. Functional status of macrophages and their value as prognostic indicators in pediatric cHL may depend on EBV status.

Lytic Epstein-Barr virus infection in epithelial cells but not in B-lymphocytes is dependent on Blimp1.

Epstein-Barr virus (EBV) replicates in superficial differentiated cells of oral hairy leukoplakia (OHL). Differentiation of squamous epithelial cells depends on B-lymphocyte-induced maturation protein 1 (Blimp1). Here we show that expression of the EBV immediate-early protein BZLF1 is restricted to Blimp1-positive epithelial cells in OHL. Luciferase assays revealed Blimp1-dependent induction of the BZLF1 promoter Zp in epithelial cell lines. Expression of ZEB1, a negative regulator of Zp, and of Xbp-1, which mediates the Blimp1 effect on Zp in B-cells, was not affected by enforced Blimp1 expression. Moreover, Xbp-1 protein expression was not detected in differentiated epithelial cells of OHL. Thus, Blimp1 induces BZLF1 expression in epithelial cells independently of ZEB1 and Xbp-1. In contrast to epithelial cells of OHL, BZLF1 expression was also observed in Blimp1-negative lymphoid cells in infectious mononucleosis tonsils, suggesting that EBV replication in B-cells may be induced independently of terminal differentiation.

Tumor microenvironment composition in pediatric classical Hodgkin lymphoma is modulated by age and Epstein-Barr virus infection.

Classical Hodgkin lymphoma (cHL) is characterized by a small number of neoplastic cells in a background of reactive cells. Children and adults differ in constitution and functionality of the immune system and it is possible that there may be age-related differences in tumor microenvironment composition in cHL. One hundred children with pediatric cHL were studied. Tumor-infiltrating lymphocytes were analyzed by immunohistochemistry (IHC) and image analysis. Epstein-Barr virus (EBV) status was determined by EBER-specific in situ hybridization and IHC. Results were analyzed in the context of age-group, histological characteristics and clinical follow-up. EBV-status was not associated with age-group. Children<10 years and EBV+ cases were characterized by a more intense T cell infiltrate, exhibiting a cytotoxic/Th1 profile, characterized by higher numbers of CD3+, CD8+, TIA1+ and TBET+ lymphocytes. Extranodal disease (p=0.016) and high number of GranzymeB+ lymphocytes (p=0.04) were independently associated with reduced progression-free survival (PFS). Yet, in EBV+ cases, improved outcome was observed in cases with low numbers of FOXP3+ lymphocytes (p=0.046), FOXP3/CD8 ratio<1 (p=0.021) and TBET/CMAF ratio<1 (p=0.017). By contrast, in EBV- cases, poor survival was observed in cases with extranodal disease (p=0.028), MC subtype (p=0.009) and high numbers of TIA1+ (p=0.044) and GranzymeB+ (p=0.04) lymphocytes. The results suggest that in EBV+ cHL an effective immune response directed against viral or tumor antigens may be triggered in the tumor microenvironment and that physiological and age-related changes of the immune system may also modulate the tumor microenvironment in pediatric cHL.

Disease patterns in pediatric classical Hodgkin lymphoma: a report from a developing area in Brazil.

Epidemiological patterns established about 20 years ago, divided classical Hodgkin lymphoma (cHL) in three entities with regard to Epstein-Barr virus (EBV) status and histological subtypes and suggested different epidemiological patterns associated with degree of economic development. Here, we investigated histopathological features and EBV association in 100 consecutive pediatric cHL cases occurring in Rio de Janeiro (Brazil). Age at diagnosis ranged from 3 to 18 years (median 14 years) with 27% of cases ≤10 years. Unexpectedly, we did not observe an early childhood peak with most cases occurring in the >10 years age group. Nodular sclerosis (NS) was the most frequent subtype (69%) and was more frequently observed in the >10 years age group, followed by mixed cellularity (MC, 23%) which was distributed equally between age groups. EBV was identified in 44.8% of cases, without preferential association with age groups (≤10 years vs. >10 years). MC cases were independently associated with EBV infection of tumour cells (p = 0.045) and with a CD4/CD20 ratio <1 in the microenvironment (p = 0.014). Our results suggest that a gradual shift from childhood peak to early adulthood peak may be observed in developing regions. The development of MC subtype may result from early exposure to EBV in the context of an impaired immune system reflected by a CD4/CD20 ratio <1. Conversely, it is possible that NS originates predominantly in the context of a better immune response against EBV and/or tumour antigens expressed in the neoplastic cells.

Cell cycle characteristics and Epstein-Barr virus are differentially associated with aggressive and non-aggressive subsets of Hodgkin lymphoma in pediatric patients.

We investigated the correlation of tumor characteristics with clinico-biological markers of aggressive disease, evaluated by Ann Arbor stage, risk group, B-symptoms, number of involved anatomic areas, mediastinal mass, nodular sclerosis (NS) grade, and risk, in pediatric Hodgkin lymphoma (HL). Leukopenia and extranodal disease influenced event-free survival (p = 0.032 and p = 0.041). In multivariate analysis, extranodal disease was associated with high number of tumor-infiltrating eosinophils (p = 0.035) and Ki67 < 50% (p = 0.024); B-symptoms with Ki67 > or =75% (p = 0.027) and high LDH levels (p = 0.001); and mediastinal mass with leukopenia (p = 0.048), NS grade II (p = 0.025), and high-risk (p = 0.046). Furthermore, low stages correlated with Ki67 > or =50% (p = 0.005) and Epstein-Barr virus (EBV) (p = 0.065). Low-risk NS was associated with EBV (p = 0.014). Hierarchical cluster analysis identified two clusters, one composed of high-risk patients and cell cycle and apoptosis features, and the other including low-risk patients, EBV, and low-risk NS. Our results show the association of biological markers with disease aggressiveness in pediatric HL.

Number of involved anatomic areas as a risk predictor in pediatric Hodgkin's lymphoma: a retrospective study.

OBJECTIVES: To determine if the number of involved anatomic areas can modify the standard risk groups in pediatric Hodgkin's lymphoma, identifying children who would benefit from a reduction in treatment intensity. METHODS: Retrospective study evaluating age, sex, histology, Ann-Arbor stage, presence of B symptoms, number of involved anatomic areas, risk grouping (favorable vs. unfavorable), and laboratory exams. All patients received doxorubicin-containing chemotherapy. Patients in complete remission for 5 years or longer were evaluated as for late effects. RESULTS: Sixty-nine patients (2-18 years) were included, 68% belonged to the unfavorable risk group. Overall survival and event-free survival were 94 and 87%, respectively. Late effects were screened in 46 cases. Advanced stage and > or = four involved anatomic areas had negative impact on event-free survival, while only the number of involved anatomic areas retained statistical significance when using Cox analysis (hazard ratio = 6.4, 95%CI = 1.08-38.33; p = 0.04). Risk groups were adjusted by number of involved anatomic areas (< four/> or = four involved anatomic areas), with a significant reallocation of patients (p = 0.008). Of the 30 patients with late effects, 21 were in the original unfavorable risk group and 14 (66.6%) could have been reallocated to the favorable risk group based on the number of involved anatomic areas. CONCLUSIONS: If re-stratification had been applied, a considerable number of children would have received less intensive treatment and, consequently, could have had lower chances of late effects. A prospective study could define if adjustment of risk group by number of involved anatomic areas would have any impact on survival rates.

Número de áreas anatômicas envolvidas como preditor de risco no linfoma de Hodgkin em crianças: um estudo retrospectivo / Number of involved anatomic areas as a risk predictor in pediatric Hodgkin's lymphoma: a retrospective study

OBJETIVO: Determinar se o número de áreas anatômicas envolvidas pode modificar os grupos de risco padrão no linfoma de Hodgkin pediátrico, identificando as crianças que poderiam se beneficiar de uma redução da intensidade do tratamento. MÉTODOS: Estudo retrospectivo com avaliação de idade, sexo, histologia, classificação de Ann-Arbor, presença de sintomas B, número de áreas anatômicas envolvidas, grupos de risco (favorável versus desfavorável) e exames laboratoriais. Todos os pacientes receberam quimioterapia com doxorrubicina. Os pacientes em remissão completa por 5 anos ou mais foram avaliados para a detecção de efeitos tardios. RESULTADOS: Sessenta e nove pacientes (2-18 anos) foram incluídos, sendo que 68 por cento pertenciam ao grupo de risco desfavorável. A sobrevida global e a sobrevida livre de eventos foram de 94 e 87 por cento, respectivamente. Os efeitos tardios foram detectados em 46 casos. Estágio avançado e > quatro áreas anatômicas envolvidas tiveram impacto negativo sobre a sobrevida livre de eventos, enquanto que o número de áreas anatômicas envolvidas apresentou significância estatística de acordo com a análise de Cox (razão de risco = 6,4; IC95 por cento = 1,08-38,33; p = 0,04). Os grupos de risco foram ajustados por número de áreas anatômicas envolvidas (< quatro/> quatro áreas anatômicas envolvidas), com uma significativa realocação de pacientes (p = 0,008). Dos 30 pacientes com efeitos tardios, 21 estavam no grupo de risco desfavorável original, e 14 poderiam ter sido realocados para o grupo de risco favorável com base no número de áreas anatômicas envolvidas. CONCLUSÃO: Se uma reestratificação tivesse sido aplicada, um número considerável de crianças teria recebido tratamento de menor intensidade e, consequentemente, poderia ter tido menores chances de apresentar efeitos tardios. Um estudo prospectivo poderia definir se o ajuste de grupos de risco pelo número de áreas anatômicas envolvidas teria algum impacto sobre ...

OBJECTIVE: To determine if the number of involved anatomic areas can modify the standard risk groups in pediatric Hodgkin's lymphoma, identifying children who would benefit from a reduction in treatment intensity. METHODS: Retrospective study evaluating age, sex, histology, Ann-Arbor stage, presence of B symptoms, number of involved anatomic areas, risk grouping (favorable vs. unfavorable), and laboratory exams. All patients received doxorubicin-containing chemotherapy. Patients in complete remission for 5 years or longer were evaluated as for late effects. RESULTS: Sixty-nine patients (2-18 years) were included, 68 percent belonged to the unfavorable risk group. Overall survival and event-free survival were 94 and 87 percent, respectively. Late effects were screened in 46 cases. Advanced stage and > four involved anatomic areas had negative impact on event-free survival, while only the number of involved anatomic areas retained statistical significance when using Cox analysis (hazard ratio = 6.4, 95 percentCI = 1.08-38.33; p = 0.04). Risk groups were adjusted by number of involved anatomic areas (< four/> four involved anatomic areas), with a significant reallocation of patients (p = 0.008). Of the 30 patients with late effects, 21 were in the original unfavorable risk group and 14 (66.6 percent) could have been reallocated to the favorable risk group based on the number of involved anatomic areas. CONCLUSION: If re-stratification had been applied, a considerable number of children would have received less intensive treatment and, consequently, could have had lower chances of late effects. A prospective study could define if adjustment of risk group by number of involved anatomic areas would have any impact on survival rates.