Proposed classification of lymphoid neoplasms for epidemiologic research from the Pathology Working Group of the International Lymphoma Epidemiology Consortium (InterLymph)

Recent evidence suggests that there is etiologic heterogeneity among the various subtypes of lymphoid neoplasms. However, epidemiologic analyses by disease subtype have proven challenging due to the numerous clinical and pathologic schemes used to classify lymphomas and lymphoid leukemias over the last several decades. On behalf of the International Lymphoma Epidemiology Consortium (InterLymph) Pathology Working Group, we present a proposed nested classification of lymphoid neoplasms to facilitate the analysis of lymphoid neoplasm subtypes in epidemiologic research. The proposed classification is based on the World Health Organization classification of lymphoid neoplasms and the International Classification of Diseases-Oncology, Third Edition (ICD-O-3). We also provide a translation into the proposed classification from previous classifications, including the Working Formulation, Revised European-American Lymphoma (REAL) classification, and ICD-O-2. We recommend that epidemiologic studies include analyses by lymphoma subtype to the most detailed extent allowable by sample size. The standardization of groupings for epidemiologic research of lymphoma subtypes is essential for comparing subtype-specific reports in the literature, harmonizing cases within a single study diagnosed using different systems, as well as combining data from multiple studies for the purpose of pooled analysis or meta-analysis, and will probably prove to be critical for elucidating etiologies of the various lymphoid neoplasms.

Current strategies and new approaches in the treatment of Hodgkin's lymphoma

As a result of continuous improvement in therapeutic options and their verification by large multicenter trials, Hodgkin's lymphoma (HL) has become one of the best curable cancers in adults. Nowadays, about 80-90% of patients in all stages achieve long-term survival. Nevertheless, these good results are threatened by treatment-associated toxicities such as infertility, cardiopulmonary toxicity and secondary malignancies. It is therefore the aim of future trial generations both to maintain excellent treatment results and to minimize late effects. At early stages, ongoing trials ask how many cycles of ABVD-like chemotherapy are necessary and if radiation doses might be further reduced or even omitted in favorable early-stage disease. In advanced stages, new combinations of chemotherapeutic drugs with higher dose densities are tested with or without the application of consolidating radiotherapy. The treatment of patients with relapsed HL depends on previous therapies with radiotherapy, chemotherapy or high-dose chemotherapy followed by autologous stem cell transplantation. For patients with multiple relapses, experimental treatment strategies include antibody- and small-molecule-based regimens. In this review we present current treatment strategies for patients with a first diagnosis of HL and relapsed HL as well as recent experimental therapeutic approaches.

Predictive and discriminating three-risk-group prognostic scoring system for staging Hodgkin lymphomas

BACKGROUND

Several 3-stage Ann Arbor classification-derived prognostic systems were constructed since 1980 to identify the prognosis of Hodgkin lymphoma (HL). Modern statistical tools were applied to 955 patients treated between 1981 and 1996 to build a 3-stage prognostic scoring system (PSS).

METHODS

Each variable associated with 10-year overall survival (10-year OS) was assigned to 2 (0 or 1) or 3 (0, 1 or 3) values. By summing the values attributed to each variable, 3 stages were defined. 10-year OS, 5-year event-free survival (5-year EFS), and freedom from progression (5-year FFP) rates of the PSS and of other existing systems were then compared.

RESULTS

Four variables were associated with 10-year OS: age (<40 = 0, >or=40 = 1), number of involved lymphoid areas (1-2 = 0, 3-4 = 1, >or=5 = 2), visceral disease (no = 0, yes = 1), and systemic symptoms (no = 0, yes = 1). Scores 0 and 1, 2 and 3, and >or=4 were attributed to 59.7%, 30.9%, and 9.4% of the patients who had 10-year OS rates of 93.5, 75.7, and 53.4% and 5-year EFS / 5-year FFP rates of 91.2%/90.3%, 78.1%/76.3%, and 54.1%/52.6%, respectively. The discrimination and prediction abilities of the PSS were better than those of the other systems tested; moreover, the PSS adequately identified the few patients with a worse prognosis without resorting to the International Prognostic Score for advanced stages. The PSS was also highly predictive for 489 patients treated between 1997 and 2002.

CONCLUSION

PSS is a useful alternative to the existing prognostic systems for evaluating HL patients.

Epidemiology and pathologic features of Hodgkin lymphoma

Hodgkin lymphoma (HL) has unique epidemiologic characteristics. The variation in incidence according to age, sex, race, socioeconomic status, and histologic subtype suggests an etiologic heterogeneity for this tumor. Epidemiologic studies have shown that both genetic and environmental factors play a role in the pathogenesis of HL. HL is one of the Epstein-Barr virus-associated lymphomas, but the oncogenetic mechanism of HL remains to be elucidated. Recent advances in molecular biology have revealed the peculiar nature of the nodular lymphocyte predominant subtype, and as a result this disease is separated from classic types of HL in the new World Health Organization classification. Reed-Sternberg (RS) cells and lymphocytic and/or histiocytic (L&H) cells originate from germinal center B-cells. Loss of the B-cell phenotype due to down-regulation of several B-cell-specific transcription factors is characteristic of RS cells in classic HL.

Expression of the human germinal center-associated lymphoma (HGAL) protein identifies a subset of classic Hodgkin lymphoma of germinal center derivation and improved survival

The human germinal-center-associated lymphoma (HGAL) gene and its cognate protein are expressed in a germinal center (GC)-specific manner. Its expression in classic Hodgkin lymphoma (cHL) prompted us to address whether HGAL expression could distinguish biologically distinct subgroups of cHL. Tissue microarrays from 145 patients treated with curative intent showed HGAL staining in 75% and was closely correlated with MUM1/IRF4 (92%) expression. BCL6 (26%), CD10 (0%), BCL2 (31%), Blimp1 (0.02%), and Epstein-Barr virus (EBV) (20%) showed no specific correlation; neither did phospho-STAT6, a key mediator of IL-4 and IL-13 signaling that induces HGAL and is implicated in cHL pathogenesis. In our study cohort, the 5-year overall survival (OS) correlated with young age (less than 45 years, P < .001), low stage (stage I and II, P = .04), and low International Prognostic Score (P = .002). In univariate analysis, HGAL expression was associated with improved OS (P = .01) and failure-free survival (FFS) (P = .05) but was not independent of other factors in multivariate analysis of OS or FFS. The expression of the GC-specific marker HGAL in a subset of cHL suggests that these cHLs retain characteristics of GC-derived lymphomas. The association with improved OS in univariate but not multivariate analysis suggests that HGAL expression is related to known clinical parameters of improved survival.

Clinicopathological analysis of 598 malignant lymphomas in Taiwan: seven-year experience in a single institution

The clinicopathological characteristics of malignant lymphomas vary according to geography. The purpose of this study is to determine the distribution and clinicopathological characteristics of malignant lymphomas in Taiwan. Archival tissue from 598 malignant lymphomas during the period of 1995-2002 was retrieved. They were reclassified according to the World Health Organization classification system. Clinical data, including age, gender, clinical staging, and follow-up, were scrutinized. There were 330 males and 268 females. The median age at onset of disease was 56 years for B-cell lymphoma (BCL), 50 years for T/NK-cell lymphoma (TCL), and 26 years for Hodgkin's lymphoma (HL). BCL accounted for 80.6%, TCL for 12.4%, and HL for 7%. The major subtypes of non-HL were diffuse large B-cell lymphoma, follicular lymphoma, plasma cell myeloma, marginal zone lymphoma of mucosa-associated lymphoid tissue type, mantle cell lymphoma, unspecified peripheral TCL, and nasal type T/NK-cell lymphoma. Nodular sclerosing subtype was the most common in HL. The frequencies of TCL and HL were relatively low. For histological subtype, enteropathy-type TCL and primary bone marrow HL had higher frequency and poorer prognosis. The 5-year overall survival of BCL, TCL, and HL was 58.9, 34.7, and 83.5%, respectively. To the best of our knowledge, this is the largest series study of malignant lymphoma in Taiwan. Immunophenotype, histological subtype, and clinical stage play significant roles in prognosis (P < 0.05).

Fine-needle aspiration diagnosis of Hodgkin lymphoma using current WHO classification—Re-evaluation of cases from 1999–2004 with new proposals

With the advent of modern therapy, the differences in prognoses and treatment regimens among different subtypes of Hodgkin lymphoma (HL) have largely vanished. Stage and the presence of systemic symptoms are much more important than histologic subtypes as predictive factors. The current (2001) WHO classification markedly de-emphasizes spatial relationships as critical to the diagnosis of lymphoma and emphasizes cell morphology, immunophenotype, genetic features, and clinical information to define the disease states. This classification, thus, greatly enhances the capability of fine-needle aspiration (FNA) to accurately diagnose HL. We searched all the FNA cases in our institute in years 1999 through 2004 and found 42 cases, for which 13 were primarily diagnosed (31.0%), 2 were recurrent (4.8%), 5 were highly suspicious (11.9%), and 22 were suspicious (52.3%) for HL. On follow-up tissue biopsy, all the primarily diagnosed, recurrent, and highly suspicious cases were confirmed to be HL (100% agreement). For the 22 suspicious cases, 13 were HL (59.1%), 5 were other lymphomas (22.8%), 1 was lymphoma unclassifiable (4.5%), and 3 were reactive processes (13.6%). The effect of immunostains on the diagnosis of HL was examined, and its importance was emphasized. Analysis of demographic data and the distribution of HL subtypes demonstrate that the study sample is representative of the general HL patient population. On the basis of these results, we propose: (1) If the FNA diagnosis of HL is confirmed both by morphology and immunostains, no further tissue confirmation, subclassification and grading is necessary, and appropriate treatment regimens should follow. (2) The nodular lymphocyte predominant HL and classical HL can be differentiated by adequate immunostaining. (3) If a definitive diagnosis cannot be achieved by FNA, a second FNA or a tissue biopsy should be recommended.

[Prevalence of lymphoma subtypes in Shanxi according to latest WHO classification]

OBJECTIVE

To analyze the prevalence of lymphoma subtypes in Shanxi according to the latest World Health Organization (WHO) classification, and to compare the figures with those in other parts of the world.

METHODS

The hematoxylin and eosin-stained sections of 447 lymphoma cases from the archive files of Shanxi Tumor Hospital were reviewed. Immunohistochemical study was performed using a panel of antibodies, including ALK1, bcl-6, CD (1a, 3, 4, 5, 7, 8, 10, 15, 20, 23, 30, 43, 56, 68, 79a and 99), cyclin D1, EMA, IgD, kappa, lambda, LMP1, PAX5, TdT and Vs38C. In addition, in-situ hybridization for Epstein-Barr virus-encoded RNA (EBER) was carried out. All cases were then reclassified according to the latest WHO classification of lymphoma.

RESULTS

Of the 447 cases studied, 385 cases (86.1%) were confirmed to be non-Hodgkin lymphoma (NHL), while 62 cases (13.9%) belonged to classic Hodgkin lymphoma (HL). Of the NHL cases, 68.3% were of B-cell lineage and 30.6% were of T and/or NK-cell lineage. Histiocytic neoplasm accounted for only 0.8% (3 cases). As for the subtyping of NHL, diffuse large B-cell lymphoma was commonest (35.1%), followed by peripheral T-cell lymphoma, NOS (12.0%), extranodal marginal zone B-cell lymphoma (MALT lymphoma) (11.7%), follicular lymphoma (8.6%), T-lymphoblastic lymphoma (7.0%), anaplastic large cell lymphoma (4.2%), B-small lymphocytic lymphoma (3.6%) and mantle cell lymphoma (2.6%). Amongst the 263 cases of B-cell lymphoma, 105 cases (39.9%) expressed immunoglobulin light chain (kappa in 52 cases and lambda in 53 cases) in paraffin sections. Regarding markers for EB virus infection, 14 cases of the B-cell lymphoma gave positive findings with both EBER in-situ hybridization and LMP-1 immunohistochemistry, while 6 of the T/NK-cell lymphoma expressed LMP-1 and 19 showed positive signals for EBER. In NHL, there was discordance in EBER in-situ hybridization and LMP-1 immunohistochemical results. As for HL, EB virus positivity was noted in 37 of the 62 cases (59.7%), including 7 cases of lymphocyte-rich HL, 11 cases of mixed cellularity HL and 19 cases of nodular sclerosis HL. In classic HL, there was complete concordance of results by both EBER in-situ hybridization and LMP-1 immunohistochemistry.

CONCLUSIONS

The prevalence of diffuse large B-cell lymphoma in Shanxi is similar to that in America, Australia, Japan and Korea. The incidence of follicular lymphoma however is much lower than America and Australia.

Immunophenotyping of Hodgkin's disease--an aid to its classification

Based on morphological, phenotypic, genotypic and clinical findings, Hodgkin's disease has recently been classified into two subtypes: Nodular lymphocyte predominant and classical Hodgkin's disease. Forty-two cases of Hodgkin's disease were subjected to detailed morphological assessment and immunophenotyping. The commonest subtype was Nodular Sclerosis seen in 27 cases. The panel of antibodies used was CD 15, CD 30, CD 3, CD 20, CD 45 and Epithelial Membrane Antigen. Immunophenotyping was done by Streptavidin Biotin Peroxidase complex technique. CD 30 was expressed in 86% and CD 15 in 76% cases. Immunophenotype helped reclassify two cases, according to the WHO classification scheme. Although morphology remains the gold standard in the diagnosis of Hodgkin's disease, immunophenotype is a useful adjunct in differentiating prognostically distinct subtypes.

The effect of Epstein-Barr virus status on clinical outcome in Hodgkin's lymphoma

The association of Epstein-Barr virus (EBV) with Hodgkin's lymphoma (HL) has been investigated over the last few years. The impact of EBV on clinical outcome is still controversial, however. In this study, we investigated the effect of EBV status on clinical outcome of HL patients. Between January 1986 and September 2004, fifty-six patients, diagnosed as having HL, were included in the analysis. Clinical data were reviewed retrospectively from the patients' records. Tissues from 56 patients were analyzed for the presence of EBV using the in situ hybridization (ISH) for EBV-encoded RNA (EBER) and immunohistochemistry for latent membrane protein (LMP)1. EBV infection was identified in 41.1% of cases by EBER ISH, 26.8% by LMP1 expression, and 26.8% by LMP1 and EBER ISH. EBER-positive HL were significantly more frequent in mixed cellularity (MC) subtype (P=0.014) and advanced stage (P=0.034). There was a trend toward shorter overall survival in EBER-positive patients without statistical significance (P=0.238). LMP1 expression also correlated with MC subtype (P=0.006) and advanced stage (P=0.007), although it did not significantly influence the survival outcome. In subgroup analysis, both EBER and LMP1 positivities were associated with longer progression-free survival in patients with age <25 years old (P=0.045). Reverse trends were shown in patients > or =25 years old. In this study, we demonstrated that the impact of tumor EBV status on prognosis may be age dependent and young patients with latent EBV infection have favorable prognosis.

Different histopathological subtypes of Hodgkin lymphoma show significantly different levels of FDG uptake

Positron emission tomography using 2-[18F]fluoro-2-deoxy-D-glucose (FDG-PET) enables quantitative analysis of metabolic activity. This study investigated standardized uptake value (SUV) levels in the different histopathological subtypes of Hodgkin lymphoma (HL). Sixty patients with newly diagnosed HL underwent staging FDG-PET/CT after lymph node biopsy. Maximum SUV in each patient (SUV(max/total)) and in each affected region or organ (SUV(max)) were recorded. Mean SUV(max/total) was 9.3 g/ml in seven nodular lymphocyte predominance (NLP) patients, 16.3 g/ml in 38 nodular sclerosis (NS) patients, 20.8 g/ml in 11 mixed cellularity (MC) patients, and 19.5 g/ml in four patients with unclassified classical HL (CHL-NOS), (ANOVA, p = 0.011). Out of 780 sites (600 lymph node regions plus 180 organs), 208 sites were found to be affected with HL. Mean SUV(max) was 8.3 g/ml in the 12 sites with NLP, 11.2 g/ml in the 147 sites affected with NS, 14.6 g/ml in the 36 sites with MC, and 13.1 g/ml in the 13 sites with CHL-NOS (ANOVA, p = 0.002). There is a significant difference in FDG/glucose uptake between the different histopathological subtypes of HL.

Lymphocyte-rich classical Hodgkin lymphoma (LRCHL): clinico-pathological characteristics and outcome of a rare entity

BACKGROUND

To investigate the proportion, clinical characteristics and outcome of lymphocyte-rich classical Hodgkin lymphoma (LRCHL) in relation to nodular lymphocyte predominant HL (NLPHL) and classical HL (cHL).

PATIENTS AND METHODS

A series of 2743 HL patients of all stages enrolled into three EORTC trials (H7, H8, H34) conducted between 1988 and 2000 and forming an unbiased series of HL patients was studied.

RESULTS

Detailed histological classification after panel review was available in 96% of the cases to allow selection of all cases with features potentially compatible with the WHO-definition of LRCHL for this study. Cases with dominance of lymphocytic infiltrate and relative paucity of eosinophils and fibrosis could be selected for re-classification. Twenty-one (0.8%) LRCHL cases were identified of which three were originally classified as NLPHL, seven as nodular sclerosis HL (NSHL) and 11 as mixed cellularity (MCHL), indicating that LRCHL is a rare disease.

CONCLUSIONS

Clinical evaluation of the unselected series of patients (n = 2743) showed that LRCHL and NLPHL cases more often presented with favorable features. Clinical outcome adjusted on ab initio patient prognosis did not differ between the three histological entities. These results strongly suggest that LRCHL corresponds to an early stage in the spectrum of cHL rather than a biologically different disease entity.

Lymphoid neoplasms in Bulgaria according to the WHO classification (2001). The experience of the National Center of Haematology

The aim of the present study was to assess the incidence of lymphoma subtypes in the largest cohort of patients in Bulgaria, referred to the National Center of Haematology and Transfusiology between 01.01.2003 and 31.12.2004, applying the WHO classification criteria, including precursor and mature cell neoplasias, plasmacytoma and Hodgkin lymphomas. A total of 790 cases were newly diagnosed. Hodgkin lymphomas comprised 24.6% of the cases, B-cell neoplasias - 66.5% whereas T/NK-cell neoplasias - 6.9% of the total. Specimens were inadequate for subclassification in 2.2% of the cases. Detailed data on the subtypes are presented and compared to reported data from other geographic locations.

Glucose-normalized standardized uptake value from (18)F-FDG PET in classifying lymphomas

Our objective was to derive the best glucose sensitivity factor (g-value) and the most discriminating standardized uptake value (SUV) normalized to glucose for classifying indolent and aggressive lymphomas.

METHODS

The maximum SUV obtained from (18)F-FDG PET over the area of biopsy in 102 patients was normalized by serum glucose ([Glc]) to a standard of 100 mg/dL. Discriminant analysis was performed by using each SUV(100) (SUV x {100/[Glc]}(g), calculated using various g-values ranging from -3.0 to 0, one at a time) as a variable against the lymphoma grades, and plotting the percentage of correct classifications against g (g-plot) to search for the best g-value in normalizing SUV(100) for classifying grades. To address the influence of the extreme glucose conditions, we repeated the same analyses in 12 patients with [Glc] < or = 70 mg/dL or [Glc] > or = 110 mg/dL.

RESULTS

SUV(100) correctly classified lymphoma grades ranging from 62% to 73% (P < 0.0005), depending on the g-value, with a maximum at a g-value of -0.5. For the subgroup with extreme glucose values, the g-plot also revealed higher and more optimal discrimination at a g-value of -0.5 (92%) than at a g-value of 0 (83%) (P = 0.03). The discrimination deteriorated at g < -1 in both analyses. The box plot for all cases using a g-value of -0.5 showed little overlap in classifying lymphoma grades. For a visually selected threshold SUV(100) of 7.25, the sensitivity, specificity, and accuracy of identifying aggressive grades were 82%, 79%, and 81%, respectively.

CONCLUSION

The results suggest that metabolic discrimination between lymphoma grades using a glucose-normalized SUV from (18)F-FDG PET is improved by introducing g-value as an extra degree of freedom.

Epstein-Barr virus is associated with all histological subtypes of Hodgkin lymphoma in Vietnamese children with special emphasis on the entity of lymphocyte predominance subtype

Early acquisition of Epstein-Barr virus (EBV) infection is prevalent in developing countries. We studied infectious mononucleosis (IM) and the subtypes of Hodgkin lymphoma (HL) with the status of EBV infection in Vietnamese children. Among the 46 cases of HL, the male-to-female ratio was 38:8, and the mean age at presentation was 6.6 years. Similar to the subtype distribution in developed countries, cases were classified as nodular sclerosis (NSHL) subtype in 56.5% (n = 26), mixed cellularity (MCHL) in 23.9% (n = 11), lymphocyte-rich classic (LRCHL) in 8.7% (n = 4), lymphocyte depletion (LDHL) subtype in 4.4% (n = 2), and nodular lymphocyte predominance (NLPHL) subtype in 6.5% (n = 3). However, in situ hybridization for EBV-encoded RNA revealed that the tumor cells were positive in 93.2% (41/44) of cases, including all 3 cases of nodular lymphocyte predominance HL. Expression of CD20 on Reed-Sternberg cells could be demonstrated in 17% (7/42) of classic HL. The high incidence of EBV in these cases of HL was correlated with an earlier mean age of presentation of primary EBV infection (ie, IM), at 5.3 years, in this patient population, compared with an average of 15 to 19 years reported in developed countries. This study demonstrates that in an area with an earlier mean age of onset of EBV infection, nearly all cases of pediatric HL, including all histological patterns, may be related to EBV infection. The association of NLPHL with EBV is unusual, and the literature is reviewed and discussed.

Malignant lymphoma in Jordan: a retrospective analysis of 347 cases according to the World Health Organization classification

BACKGROUND

Most studies describing the subtypes of lymphoma in Jordan were carried out in the 1980s at a time when immunohistochemical facilities were unavailable. Using a database established after immunohistochemical studies were introduced, we determined the frequency of the various types of nodal and extranodal lymphomas in the adult and paediatric Jordanian population. We also assessed the incidence of bone marrow involvement at the initial presentation for each lymphoma type.

METHODS

A retrospective analysis of the histopathological subtypes of various lymphomas was conducted on all primary lymphoma cases diagnosed during a 3-year period between January 2001 and December 2003.

RESULTS

Of 347 patients included in the study, 78.4% had non-Hodgkin's lymphoma (NHL) and 21.6% had Hodgkin's lymphoma (HL). In the NHL group, diffuse large B-cell lymphoma was the most common (28.2%) followed by follicular lymphoma (15.6%). In the HL group, the nodular sclerosis variant was the most frequent (7.8%) followed by the mixed cellularity type (5.5%). Of all the lymphoma cases, the highest incidence of marrow involvement was seen in patients with lymphoplasmacytic lymphoma. Forty-nine patients were children (age <15 years) in whom Burkitt's lymphoma (15 cases) and HL (14 cases) were the commonest subtypes. One-hundred six patients with primary extranodal lymphomas (ENL) accounted for 30.5% of all lymphomas.

CONCLUSIONS

There is a higher incidence of NHL in Jordan compared with other series in the Middle East. Among the various lymphomas, diffuse large B-cell lymphoma is the most commonly encountered lymphoma in adults. Burkitt's lymphoma and Hodgkin's disease are the most frequent childhood lymphomas, followed closely by lymphoblastic lymphoma.

Lymphocyte-Rich Classical Hodgkin's Lymphoma: Clinical Presentation and Treatment Outcome in 100 Patients Treated Within German Hodgkin's Study Group Trials

Purpose

To investigate the clinical characteristics and treatment outcome of patients with lymphocyte-rich classical Hodgkin's lymphoma (LRCHL) compared with other histologic subtypes of Hodgkin's lymphoma (HL).

Patients and Methods

From a total of 2,715 patients with biopsy-proven HL treated within the trials HD7 to HD12 of the German Hodgkin's Study Group, 100 patients (4%) with LRCHL, 145 patients (5%) with lymphocyte-predominant HL (LPHL), 1,688 patients (62%) with nodular sclerosis, 731 patients (27%) with mixed cellularity, and 23 patients (1%) with lymphocyte depletion were identified. Patients with LRCHL had a median age of 38 years (range, 16 to 74 years).

Results

Compared with other histologic subtypes, patients with LRCHL are, on average, older and usually present with early stages of disease (stage I, 34%; stage II, 46%). The median time of follow-up was 32.2 months (95% CI, 28.2 to 37.0 months). Complete and partial remission was achieved in 96 patients (96%) and four patients (4%), respectively, with LRCHL. The event-free and overall survival rates were 97% (95% CI, 96.7% to 96.9%) and 97% (95% CI, 96.8% to 97.0%), respectively, at 30 months. Only three patients died; all of the deaths were caused by treatment-related toxicities.

Conclusion

LRCHL is a distinct subtype of CHL, with features of CHL and LPHL, and is a rare entity accounting for only 4% of HLs. LRCHL has a different pattern of clinical presentation and age and sex distribution than other CHLs. It is associated with an excellent prognosis if treated with current treatment regimens. When treating patients with LRCHL, great attention should be paid to avoid acute toxicities.

Lymphocyte-predominant and classical Hodgkin's lymphoma--comparison of outcomes

INTRODUCTION

Lymphocyte predominant Hodgkin's lymphoma (LPHL) differs in histological and clinical presentation from classical Hodgkin's lymphoma (cHL). Treatment of LPHL patients using standard Hodgkin's lymphoma (HL) protocols leads to complete remission (CR) in more than 95% of patients. However, differences in terms of relapse rates, survival and freedom from treatment failure (FFTF) between LPHL and cHL patients were suggested by a recent intergroup analysis. To obtain a more comprehensive picture, we reviewed all LPHL-cases registered in the GHSG database and compared patient characteristics and treatment outcome with cHL patients.

PATIENTS AND METHODS

We retrospectively analyzed 8298 HL patients treated within the GHSG trials (HD4-HD12): 394 LPHL patients and 7904 cHL patients. From 394 LPHL patients 63% were in early stage, 16% in intermediate and 21% in advanced stage of disease. Of the 7904 cHL patients analyzed, 22% were in early, 39% in intermediate and 39% in advanced stages. About 9% of LPHL patients had B symptoms compared to 40% in cHL patients.

RESULTS

About 91% LPHL vs. 86% cHL patients in early stages, 86% vs. 83% in intermediate and 79% vs. 75% in advanced stages reached CR/CRu. Additional analysis for LPHL IA patients showed 98% CR/CRu after extended field, 100% after involved field (IF) and 98% CR/CRu after combined modality treatment. About 0.3% LPHL patients developed progressive disease (PD) compared to 3.7% cHL patients. The relapse rate of LPHL patients was very similar to cHL (8.1% vs. 7.9%). There were 2.5% secondary malignancies in LPHL and 3.7% in cHL patients. About 4.3% LPHL patients and 8.8% cHL patients died. The FFTF rates for LPHL and cHL patients at a median observation of 41 or 48 months were 92% and 84%, respectively. The OS for LPHL and cHL patients was 96% and 92%, respectively.

CONCLUSION

The cHL patients present more frequently with advanced stages and B symptoms compared to LPHL patients. There was no difference in treatment outcome in terms of CR/CRu, PD and mortality between LPHL and HL. Surprisingly, there were also no differences in patients with relapse.

Special issues in pediatric Hodgkin's disease

Childhood Hodgkin's disease (HD) is not a biologically unique disease; it differs from adult HD primarily in the relative incidence of disease histology. Preadolescent children are more likely to have Mixed Cellularity and nodular lymphocyte predominant HD. Adolescent and young adult HD is indistinguishable, with a predominance of nodular sclerosing (NS) HD. Nonetheless, treatment paradigms have diverged over the years as pediatric oncologists responded first to developmental issues in the young child, and later to the long-term treatment consequences in all young survivors. The latter concerns are of equal relevance to the young adult with HD. The increasing convergence of treatment approaches in the past decade is therefore most appropriate. Reproductive potential, risk of secondary malignancy and cardiopulmonary consequences of therapy have driven the pediatric treatment paradigm of care. Chemotherapy with low dose, limited field radiation is standard, with low-stage patients often treated by chemotherapy alone. Algorithms tailor therapy to response. The prognostic importance of very early chemotherapy response rather than end-of-chemotherapy response has led the Children's Oncology Group to use early response (after 6 wk) to titrate individual therapy and dense regimens to maximize the early response rates. Although the dose dense regimens of adult groups are similar, the pediatric algorithms emphasize using the enhanced efficacy to limit cumulative therapy. This review intends to address the special issues of childhood HD, with the intent of further encouraging understanding that will foster convergence of pediatric and adult treatment paradigms.

Non-mediastinal grey zone lymphomas and report from the workshop

Grey zone lymphomas represent borderline lesions between classical Hodgkin lymphoma (cHL) and other morphologically and immunophenotypically related diseases and entities like nodular lymphocyte predominant HL, T-cell rich B-cell lymphoma, ALK-negative anaplastic large cell lymphoma (ALCL), diffuse large B cell lymphoma (DLBCL) anaplastic variant and primary mediastinal LBCL. The sharp definition of morphological, immunophenotypical and molecular features of the "text-book cases" of each disease and the comparison with grey zone cases has reduced most of the latter cases. Two reports in this workshop dealt with the problematic non-mediastinal grey zone lymphomas, one with a cHL of T cell-type presenting in the skin as a ALK-negative ALCL and the other with the grey zone between cHL of B-cell type and ALK-negative ALCL.

Histological classification of 1,025 cases of Hodgkin's lymphoma from the State of São Paulo, Brazil

CONTEXT AND OBJECTIVE

It is currently asserted that, in industrialized countries, nodular sclerosis is the most frequent type of Hodgkin's lymphoma, in contrast to developing countries, where mixed cellularity and lymphocyte depletion are more frequently seen. The objective was to review histological data from cases of Hodgkin's lymphoma from São Paulo and Campinas cities.

DESIGN AND SETTING

Cross-sectional histopathological analysis, in four university hospitals and one cancer care center.

METHODS

1,025 cases diagnosed as Hodgkin's lymphoma between 1990 and 2000 were collected from five institutions; 631 of them (61.5%) had been immunophenotyped using antibodies to CD20, CD3, CD15 and CD30. The relative frequencies of histological types (as informed by the contributing authors, who are hematopathologists in their institutions) were determined according to age and gender.

RESULTS

The Hodgkin's lymphoma types were distributed as follows: lymphocyte predominance 4.8%, nodular sclerosis 69.2%, mixed cellularity 21.1% and lymphocyte depletion 4.6%.

CONCLUSIONS

The controversy regarding the frequencies of Hodgkin's lymphoma types within the Brazilian setting seems to be due to the small number of cases in previous studies. The present data show a picture close to the situation in the industrialized countries.

Immunohistochemical analysis of Hodgkin's disease in Kampala, Uganda

BACKGROUND

Histopathological examination remains crucial for diagnosis and classification of Hodgkin's disease (HD) but poses problems when characteristic features of HD are not present and hence the value of immunohistochemistry. Experience with immunohistochemistry in developing countries is limited due to cost.

OBJECTIVE

To describe the immunophenotypic and histologic types of Hodgkin's disease in Kampala, Uganda

DESIGN

A cross-sectional study.

SETTING

Makerere University Medical School, Department of Pathology.

METHODOLOGY

Two hundred formalin fixed, paraffin- embedded biopsies, which had been previously diagnosed as Hodgkin's disease in the Makerere University, Department of Pathology from 1980--2000, were re-assessed with haematoxylin and eosin. The sections were then subjected to immunohistochemistry using monoclonal antibodies: leucocyte common antigen (CD45), antibodies to Reed-Sternberg cells (CD15, CD30) and to B cells (CD20).

RESULTS

Of the 200 biopsies, 171 (71.3%) were diagnosed as Hodgkin's disease using immunohistochemistry. The mean age of the 171 cases was 26.1(SD 16.2) years; mode 20.0; median 22.5 years. The 15-24 year age group was most affected (47.2%). There were more males (65.9%) than females and most were Baganda who are the main tribe in the central region of Uganda. Mixed cellularity (35.7 %) and lymphocyte depleted (24.6 %) HD were the commonest histological types. Classic HD (CD30, CD 15, CD20, CD45) was the most commonest (77.8%) immunophenotype.

CONCLUSION

Classic Hodgkin's disease (CD30, CD 15, CD20 and CD45) is the most commonest immunophenotype in Kampala, Uganda, and mixed cellularity and Iymphocyte depleted are the main histologic subtypes.