B-cell non-Hodgkin Lymphoma (b-cell + non-hodgkin_lymphoma)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Nuclear morphometry and texture analysis of B-cell non-Hodgkin lymphoma: Utility in subclassification on cytosmears

DIAGNOSTIC CYTOPATHOLOGY, Issue 2 2010
Shilpa Gupta M.D.
Abstract Non-Hodgkin lymphoma (NHL) is a heterogeneous group of lymphoid neoplasms and accurate subclassification is an essential prerequisite for proper management of patients. This study was aimed at evaluating the utility of nuclear morphometry and textural features on cytology smears to classify the cases of NHL on aspiration cytology. Fine needle aspiration smears of 50 cases of B-cell NHL were included. Various morphometric and texture parameters were obtained by manually tracing the nuclei on digitized images in each case and discriminant analysis performed using various features taken individually as well as all together. The percentage of cells correctly classified to a particular NHL subtype using the discriminant functions so obtained was noted. Our results show that discriminant analysis done on size parameters could correctly classify a greater number of cells than on shape parameters (36.4% vs. 21.2%, respectively). Texture parameters based on single pixel values (first order texture) were inferior (42.8%) to those based on pair of pixels (58.7%) in subtyping of cells. Discriminant analysis based on color parameters was more effective (61.9%) as compared to rest of the morphometric and textural parameters. Using all the morphometric and textural parameters together, 83.3% of cells could be correctly classified to a particular NHL subtype. The present study, perhaps the first study of detailed morphometric analysis on cytosmears, shows that satisfactory classification of NHL on aspiration cytology is possible using nuclear morphometry and textural parameters considered together. These results are promising for further studies on this subject and development of automated cytodiagnosis. Diagn. Cytopathol. 2010. © 2009 Wiley-Liss, Inc. [source]


Mixed cryoglobulinemia is associated with increased risk for death, or neoplasia in HIV-1 infection

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2001
T. Kordossis
Backround Cryoglobulinemia has been reported in several chronic infectious and autoimmune diseases, and in patients with HIV-1 infection. Cryoglobulinemia associated with hepatitis C virus infection is considered a risk factor for the development of neoplasia, especially B-cell non-Hodgkin lymphoma. This study was undertaken to investigate whether the presence of circulating cryoglobulins is associated with survival or development of neoplastic disease in HIV-1 infection. Design We evaluated 87 unselected consecutive HIV-1 infected patients for the presence of cryoglobulinemia and they were prospectively followed up for a median of 34 months, with clinic visits at 4-month intervals. None of the patients had neoplasia at study entry. Time-to-event analysis for death, neoplasm and B-cell lymphoproliferative disorder were performed with Cox proportional hazards models. Results Mixed cryoglobulinemia (types II and III) was detected in 24 (28%) of the 87 patients. During the follow up, 12 patients died and 8 developed neoplastic disease. Multivariate analysis showed that circulating cryoglobulins were an independent predictor of death [relative risk (RR), 4·97; 95% confidence intervals (CI), 1·26,19·63] and development of neoplasia (RR, 5·18; 95% CI, 1·23,21·83). In addition, cryoglobulinemia reached borderline significance as a predictor of lymphoproliferative disorder of B-cell origin (P = 0·08; RR, 4·53; 95% CI, 0·83,24·75). Conclusions Our results suggest that cryoglobulinemia is associated with an increased risk for death, neoplasia or development of lymphoproliferative disorder of B-cell origin, in HIV-1 infected patients. [source]


Clonally related splenic marginal zone lymphoma and Hodgkin lymphoma with unmutated V gene rearrangements and a 15-yr time gap between diagnoses

EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2004
Richard Rosenquist
Abstract:, Hodgkin lymphoma (HL) can rarely occur during the course of B-cell non-Hodgkin lymphoma (B-NHL), where both the HL and NHL tumours have been reported to be clonally related in most of the few combination lymphomas so far investigated. We here investigated a case that developed HL 15 yr after being diagnosed with an indolent B-cell lymphoma, classified as a splenic marginal zone lymphoma (SMZL). Analysis of rearranged immunoglobulin genes in the SMZL clone and in single Hodgkin Reed,Sternberg cells revealed presence of identical V gene rearrangements, thus demonstrating a clonal relationship. In contrast to previously described B-NHL/HL combinations, in this case both types of tumour cells carried unmutated V gene rearrangements. We conclude that the HL evolved from an unmutated tumour precursor, either the SMZL clone itself or a common earlier precursor. [source]


Expression of HYAL2 mRNA, hyaluronan and hyaluronidase in B-cell non-Hodgkin lymphoma: Relationship with tumor aggressiveness

INTERNATIONAL JOURNAL OF CANCER, Issue 2 2005
Philippe Bertrand
Abstract Hyaluronidases and their substrate, hyaluronan (HA), were mainly explored in solid tumors but rarely in hematologic malignancies. While HA involvement was demonstrated in invasion and metastasis in most cases of solid tumors, the role of hyaluronidases in cancer progression remains controversial. One of the hyaluronidases, HYAL2, is suspected to be involved in the first step of HA degradation. In this work, HYAL2 mRNA, HA and total hyaluronidases expression were examined in lymphoma tissue extracts and correlated to the lymphoma subtype. Real-time RT-PCR was performed to evaluate HYAL2 mRNA. HA and hyaluronidase were assayed by enzyme-linked sorbent assay. Our results showed that HYAL2 mRNA expression was correlated to lymphoma diagnosis (p = 6 × 10,3) and was significantly lower in high-grade lymphoma, i.e., diffuse large B-cell diffuse lymphomas (DLBCLs). Several forms of hyaluronidase were detected by zymography and total hyaluronidase activity detected in tissue extracts was not significantly different according to tumor grade. HA levels also correlated to lymphoma subtype (p = 1 × 10,5) and were higher in DLBCLs. Moreover, HYAL2 mRNA and HA expressions were inversely correlated (p = 0.035). HYAL2 gene is localized on chromosome 3p21, which contains candidates tumor suppressor genes. Our results suggest that HYAL2 may have a prognostic significance in lymphomas and an antioncogenic activity. Conversely, HA overexpression in high-grade lymphomas is in favor of its involvement in tumor development and could provide a useful target for lymphoma therapy using HA-binding peptides. [source]


Outcome of children with B cell lymphoma in Venezuela with the LMB-89 protocol

PEDIATRIC BLOOD & CANCER, Issue 5 2004
G. Acquatella MD
Abstract Background We analyzed the results of the LMB-89 protocol performed in seven centers in Venezuela in 96 children having B-cell non-Hodgkin lymphoma treated from 1995 to 2002. Procedure Mean age was 7.1 years with 71 (74%) been male. Eighty-two patients (85%) had diffuse small cell lymphoma Burkitt and Burkitt-like, and 14 (15%) had diffuse large B-cell lymphoma. Initial disease sites included the abdomen in 67%, peripheral nodes in 8%, and mediastinal in 4%. Treatment was directed to risk groups as described for LMB-89 protocol. Group A: seven patients (7%), group B: 80 patients (83%), and group C: nine patients (9%). Results Mean follow-up was 35,±,31 months. Complete remission (CR) occurred in 70 patients (73%); four patients (6%) had relapse during the first year and ten patients (10%) had progressive disease. Overall survival (OS) and event free survival (EFS) were 85 and 80% at 1 year, and 82 and 75% at 2 years, respectively. The EFS by therapeutic groups at 3 years was A: 100%; B: 76%, and C: 56%. Toxicity: neutropenia in 75%, thrombocytopenia in 63%, febrile neutropenia in 39%. Viral infections: hepatitis B in 20%, hepatitis C in 2%, and Herpes zoster in 3%. Tumor lysis syndrome (TLS) occurred in 9% during induction phase with a high mortality of 44% (urate-oxidase was available only at the end of the study). Conclusions The high mortality rate during induction phase prohibited a better EFS. Prophylactic use of xantine-oxidase may improve future results. The high incidence of hepatitis B requires a vaccination program. © 2004 Wiley-Liss, Inc. [source]


Phase II study of bryostatin 1 and vincristine for aggressive non-Hodgkin lymphoma relapsing after an autologous stem cell transplant,

AMERICAN JOURNAL OF HEMATOLOGY, Issue 8 2009
Paul M. Barr
Bryostatin 1, isolated from a marine bryozoan, enhances the efficacy of cytotoxic agents through modulation of the protein kinase C pathway and is active in combination with vincristine for diffuse large B-cell lymphoma. Further, the apoptotic frequency of peripheral blood T lymphocytes as determined by flow cytometry may predict which patients will respond to this combination. We tested the efficacy and safety of bryostatin 1 50 ,g/m2 given over 24 hr and vincristine 1.4 mg/m2 on days 1 and 15 every 28 days in aggressive B-cell non-Hodgkin lymphoma (NHL) relapsing after autologous stem cell transplantation. End points included tumor response, toxicity, and survival. Responses were correlated with an increase in apoptotic frequency of CD5+ cells by flow cytometry using annexin V staining. Fourteen patients were enrolled with 13 being evaluable for a response. The overall response rate was 31% with two patients achieving a complete response. The most common toxicities were Grade 3 lymphopenia (seven patients), Grade 3 to 4 neutropenia (two patients), and Grade 3 hypophosphatemia (two patients). Median progression-free and overall survivals for all patients were 5.7 and 21.4 months, respectively. One patient demonstrated an increase in T-cell apoptotic frequency, also achieving a complete response. Bryostatin 1 and vincristine have efficacy in select patients with aggressive NHL. Future investigations of agents targeting the protein kinase C pathway may benefit from early response assessment using flow cytometry to evaluate T-cell apoptosis. Am. J. Hematol., 2009. © 2009 Wiley-Liss, Inc. [source]


Response of myasthenia gravis to rituximab in a patient with non-Hodgkin lymphoma

AMERICAN JOURNAL OF HEMATOLOGY, Issue 2 2004
Ajeet Gajra
Abstract Myasthenia gravis is a B-cell-mediated autoimmune neuromuscular disorder characterized by weakness and fatigability of skeletal muscles. The underlying defect is an autoantibody-mediated attack on the acetylcholine receptors (AchRs) at the neuromuscular junction. Rituximab is a genetically engineered chimeric murine/human monoclonal antibody indicated for treatment of patients with low-grade or follicular, CD20-positive, B-cell non-Hodgkin lymphoma. Based on its potential for elimination of auto-reactive B-cell clones, rituximab may have a role in the management of some autoimmune disorders. We report a patient with B-cell, follicular non-Hodgkin lymphoma and a long-standing history of myasthenia gravis and the favorable impact of rituximab on both disorders. Am. J. Hematol. 77:196,197, 2004. © 2004 Wiley-Liss, Inc. [source]


High activity 90Y-ibritumomab tiuxetan (Zevalin®) with peripheral blood progenitor cells support in patients with refractory/resistant B-cell non-Hodgkin lymphomas

BRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2007
Pier F. Ferrucci
Summary Radioimmunotherapy (RIT) is an alternative approach in the treatment of resistant/refractory B-cell non-Hodgkin lymphoma (NHL). We performed a feasibility and toxicity pilot study of escalating activity of 90Y-ibritumomab tiuxetan followed by autologous stem cell transplantation (ASCT). Three activity levels were fixed , 30 MBq/kg (0·8 mCi/kg), 45 MBq/kg (1·2 mCi/kg) and 56 MBq/kg (1·5 mCi/kg) , and 13 patients enrolled. One week before treatment all patients underwent dosimetry. ASCT was performed 13 d after Zevalin® administration. Treatment was well tolerated and all patients engrafted promptly. No differences in terms of haematological toxicities were observed among the three levels, apart from a delayed platelet recovery in heavily pretreated patients receiving 56 MBq/kg. Non-haematologic toxicity was mainly related to infections and liver toxicity. One patient died 4 months after treatment because of hepatitis C virus reactivation. One patient developed a myelodysplastic syndrome 2 years after treatment. In conclusion, high-activity Zevalin® with ASCT is feasible and could be safely delivered in elderly and heavily pretreated NHL patients, including those who previously received high-dose chemotherapy and ASCT. Maximum tolerated dose was not clearly defined according to dosimetry and clinical toxicities, and further studies are needed to confirm the toxicity profile and evaluate efficacy. [source]


Frequent occurrence of B-cell lymphomas in angioimmunoblastic T-cell lymphoma and proliferation of Epstein,Barr virus-infected cells in early cases

BRITISH JOURNAL OF HAEMATOLOGY, Issue 6 2007
Klaus Willenbrock
Summary Secondary lymphomas occurring in the setting of angioimmunoblastic T-cell lymphoma (AILT) are considered to be rare. Their occurrence has been attributed to Epstein,Barr virus (EBV)-associated lymphoproliferations. A previous study detected a dysregulated hypermutation process in B-cells of AILT. The present study aimed at estimating the frequency of B-cell lymphomas in AILT. By studying the expression of EBV and activation-induced cytidine deaminase (AID) as an indicator of hypermutating cells, we assessed whether B-cell lymphoproliferations in AILT were strictly associated with EBV and whether hypermutation might contribute to lymphomagenesis. Among 161 cases of AILT, diagnosed between 1996 and 2005 at the lymph node registry, Frankfurt, Germany, 19 cases were detected that also had B-cell non-Hodgkin lymphoma (NHL) and two cases had classical Hodgkin lymphoma (HL). EBV was detected in tumour cells of 7/18 NHL and both HL, suggesting that factors other than EBV contribute to lymphomagenesis. AID was expressed in AILT in large cells disseminated in the tissue, implying that the process of somatic hypermutation is ongoing in AILT, although the GC architecture is disrupted. This might be relevant in the development of secondary lymphomas. [source]


Cost utility in the United States of rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone for the treatment of elderly patients with diffuse large B-cell lymphoma,

CANCER, Issue 8 2005
John C. Hornberger M.D., M.S.
Abstract BACKGROUND Findings from the Groupe d'Etude des Lymphomes Adultes LNH 98-5 study showed that rituximab added to combined cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) prolonged progression-free survival and overall survival in adults age , 60 years with diffuse large B-cell non-Hodgkin lymphoma (DLBCL). The current study was conducted to investigate the incremental cost utility of the addition of rituximab to CHOP (R-CHOP) compared with CHOP alone. METHODS Clinical prognosis of the time to disease progression and death was estimated using published evidence from the LNH 98-5 study (n = 399 patients) that was linked mathematically to published long-term outcome data on patients with DLBCL. Drug-acquisition costs were based on published data from formulary pricing sources, and the costs of cancer surveillance and end-of-life care were based on published literature sources. The authors assessed cost utility as the difference in costs between R-CHOP and CHOP divided by the increase in expected overall survival adjusted for quality of life. RESULTS Over 5 years, it was projected that R-CHOP would prolong overall survival by 1.04 years. The mean cumulative cost of CHOP was $3358, and the mean cost of R-CHOP was $17,225, resulting in a cumulative net increase of $13,867. The posttreatment cancer surveillance cost for CHOP was $3950, compared with $5202 for R-CHOP. It was estimated that R-CHOP would have a cost-utility ratio of $19,297 per year of life gained compared with CHOP when adjusted for quality of life. R-CHOP remained cost effective over wide ranges of variables in sensitivity analyses. CONCLUSIONS Compared with CHOP alone, it was predicted that R-CHOP would be cost effective in elderly patients with DLBCL. Cancer 2005. © 2005 American Cancer Society. [source]


Randomized phase II study of concurrent and sequential rituximab and CHOP chemotherapy in untreated indolent B-cell lymphoma

CANCER SCIENCE, Issue 4 2006
Michinori Ogura
CHOP combined with rituximab (R-CHOP) is regarded as one of the most effective treatments for indolent B-cell non-Hodgkin lymphoma (B-NHL), however, its optimal combination schedule remains unknown. We performed a randomized phase II study to explore a more promising schedule in untreated, advanced indolent B-NHL. Patients were randomized to receive either six courses of CHOP concurrently with rituximab (Arm C), or six courses of CHOP followed by six courses of weekly rituximab (Arm S). A total of 69 patients received the concurrent (n = 34) or sequential (n = 35) regimen. Overall response rate (ORR) in Arm C was 94% (95% confidence interval [CI], 79 to 99), including a 66% complete response (CR) compared with 97% (95% CI, 85,100), including a 68% CR in Arm S. Patients in Arm C experienced more grade 4 neutropenia (85%versus 70%) and experienced more grade 3 or greater non-hematological toxicities (21%versus 12%). Both arms were tolerated well. With a median follow-up of 28.2 months, the median progression-free survival (PFS) time was 34.2 months in Arm C, and was not reached in Arm S. R-CHOP is highly effective in untreated indolent B-NHL, either concurrent or in a sequential combination. Both combination schedules deserve further investigation. (Cancer Sci 2006; 97: 305 , 312) [source]


Genetic and phenotypic analysis of B-cell post-transplant lymphoproliferative disorders provides insights into disease biology

HEMATOLOGICAL ONCOLOGY, Issue 4 2008
Efsevia Vakiani
Abstract B-cell post-transplant lymphoproliferative disorders (PTLD) are classified as early lesions, polymorphic lymphomas (P-PTLD) and monomorphic lymphomas (M-PTLD). These morphologic categories are thought to reflect a biologic continuum, although supporting genetic data are lacking. To gain better insights into PTLD pathogenesis, we characterized the phenotypes, immunoglobulin (Ig) gene alterations and non-Ig gene (BCL6, RhoH/TTF, c-MYC, PAX5, CIITA, BCL7A, PIM1) mutations of 21 PTLD, including an IM-like lesion, 8 P-PTLD and 12 M-PTLD. Gene expression profile analysis was also performed in 12 cases. All PTLD with clonal Ig rearrangements showed evidence of germinal centre (GC) transit based on the analysis of Ig and BCL6 gene mutations, and 74% had a non-GC phenotype (BCL6,±,MUM1+). Although surface Ig abnormalities were seen in 6/19 (32%) PTLD, only three showed ,crippling' Ig mutations indicating other etiologies for loss of the B-cell receptor. Aberrant somatic hypermutation (ASHM) was almost exclusively observed in M-PTLD (8/12 vs. 1/8 P-PTLD) and all three recurrent cases analysed showed additional mutations in genes targeted by ASHM. Gene expression analysis showed distinct clustering of PTLD compared to B-cell non-Hodgkin lymphomas (B-NHL) without segregation of P-PTLD from non-GC M-PTLD or EBV+ from EBV, PTLD. The gene expression pattern of PTLD appeared more related to that of memory and activated B-cells. Together, our results suggest that PTLD represent a distinct type of B-NHL deriving from an antigen experienced B-cell, whose evolution is associated with accrual of genetic lesions. Copyright © 2008 John Wiley & Sons, Ltd. [source]


High activity 90Y-ibritumomab tiuxetan (Zevalin®) with peripheral blood progenitor cells support in patients with refractory/resistant B-cell non-Hodgkin lymphomas

BRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2007
Pier F. Ferrucci
Summary Radioimmunotherapy (RIT) is an alternative approach in the treatment of resistant/refractory B-cell non-Hodgkin lymphoma (NHL). We performed a feasibility and toxicity pilot study of escalating activity of 90Y-ibritumomab tiuxetan followed by autologous stem cell transplantation (ASCT). Three activity levels were fixed , 30 MBq/kg (0·8 mCi/kg), 45 MBq/kg (1·2 mCi/kg) and 56 MBq/kg (1·5 mCi/kg) , and 13 patients enrolled. One week before treatment all patients underwent dosimetry. ASCT was performed 13 d after Zevalin® administration. Treatment was well tolerated and all patients engrafted promptly. No differences in terms of haematological toxicities were observed among the three levels, apart from a delayed platelet recovery in heavily pretreated patients receiving 56 MBq/kg. Non-haematologic toxicity was mainly related to infections and liver toxicity. One patient died 4 months after treatment because of hepatitis C virus reactivation. One patient developed a myelodysplastic syndrome 2 years after treatment. In conclusion, high-activity Zevalin® with ASCT is feasible and could be safely delivered in elderly and heavily pretreated NHL patients, including those who previously received high-dose chemotherapy and ASCT. Maximum tolerated dose was not clearly defined according to dosimetry and clinical toxicities, and further studies are needed to confirm the toxicity profile and evaluate efficacy. [source]


Analysis of proliferating cell fraction determined by monoclonal antibody to M1-subunit ribonucleotide reductase and Ki-67 in relation to p53 protein expression in fine-needle aspirates from non-Hodgkin's lymphomas

CYTOPATHOLOGY, Issue 5 2000
V. Sviatoha
Analysis of proliferating cell fraction determined by monoclonal antibody to M1-subunit ribonucleotide reductase and Ki-67 in relation to p53 protein expression in fine-needle aspirates from non Hodgkin's lymphomas The purpose of this study was to analyse the proliferative fraction with the monoclonal antibody M1-R-R to M1-subunit ribonucleotide reductase and with MIB-1 to Ki-67 antigen in relation to p53 protein expression in fine needle aspirates from B-cell non-Hodgkin's lymphomas. One hundred and thirty-seven cases, previously diagnosed and sub-typed according to the Kiel classification and characterized by immunophenotyping, were included in the study. The M-1 subunit ribonucleotide reductase (M1 -R-R), Ki-67 and p53 antigens were detected using monoclonal antibodies on stored cytospin preparations. There was a good correlation (r = 0.72) between Ki-67 and M1 -R-R positive cell fraction in both high and low grade lymphomas. High-grade lymphomas had a median percentage of M1 -R-R/MIB-1 positive cells of 53.0/73.0 for lymphoblastic, 61.0/52.0 for immunoblastic and 33.5/41.0 for centroblastic lymphomas, respectively. In low grade lymphomas figures of median percentage of M1 -R-R/MIB-1 were 9.0/15.0 for centroblastic/centrocytic, 11.0/9.5 for chronic lymphocytic leukaemia, 16.0/27.0 for centrocytic and 12.0/9.0 for immunocytomas, respectively. The median percentages of M1 -R-R/MIB-1 for high and low grade lymphomas were 37.0/50.5 and 11.0/12.0, respectively. In the p53 positive cases the proliferation rate as measured by staining for M1 -R-R and MIB-1 was higher than in p53 negative cases, but the difference was not statistically significant. The results show that cytospin material obtained by fine needle aspiration and stored at ,70 °C for years can be used reliably for both peroxidase-avidin-biotin and three-step alkaline phosphatase immunocytochemical staining. In addition, proliferation fraction determined by M1 -R-R monoclonal antibody staining correlates well with that measured by an established marker for cell proliferation, the Ki-67 antibody. However, the proliferation fraction as measured by the two antibodies differs in the various subtypes of non-Hodgkin's lymphoma which indicates that they may contribute different prognostic information. [source]


Quantitative microsatellite analysis to delineate the commonly deleted region 1p22.3 in mantle cell lymphomas

GENES, CHROMOSOMES AND CANCER, Issue 10 2006
Asha Balakrishnan
The molecular pathogenesis of mantle cell lymphomas (MCL), a subset of B-cell non-Hodgkin's lymphomas with a poor prognosis, is still poorly understood. In addition to the characteristic primary genetic alteration t(11;14)(q13;q32), several further genetic changes are present in most cases. One of the most frequent genomic imbalances is the deletion of 1p22.1,p31.1 observed in nearly one-third of MCL cases. This might indicate the presence of tumor suppressor gene(s) in this critical region of deletion. Quantitative microsatellite analysis (QuMA) is a real-time PCR-based method to detect DNA copy number changes. Since QuMA has the resolving power to detect subtle genomic alterations, including homozygous deletions, this may help to identify candidate tumor suppressor genes from deleted regions. To gain more insight into the molecular pathogenesis of MCL, QuMA was performed on genomic DNA from 57 MCL cases. Eight microsatellite loci mapping to the chromosomal region 1p22.3 were analyzed. Losses were observed in 51 of the 57 (,89.5%) samples. Two cases showed a homozygous deletion at the locus containing the gene SH3GLB1, which plays a key role in Bax-mediated apoptosis. Two hotspots with copy number losses were detected at chromosomal localizations 85.4 and 86.6 Mb encompassing BCL10 and CLCA2. Both the genes seem to be attractive candidates to study tumor suppressor function in MCL. This article contains Supplementary material available at http://www.interscience.wiley.com/jpages/1045,2257/suppmat. © 2006 Wiley-Liss, Inc. [source]


Pathology of lymphoma progression

HISTOPATHOLOGY, Issue 4 2001
H K Müller-Hermelink
Reflecting the stepwise process of oncogenesis, lymphomas may cumulatively develop a more aggressive phenotype during the course of disease, a process referred to as lymphoma progression. Although morphological, clinical and biological aspects of lymphoma progression do not always overlap, changes in lymphoma morphology frequently indicate alterations in the clinical and biological behaviour of the disease. Indolent and aggressive lymphomas in disease progression can either be clonally related or represent clonally unrelated neoplasms. We propose to use the term ,lymphoma progression' in a biological sense denoting only clonal development of and within a lymphoma entity. The term ,composite lymphoma' should be used as a merely descriptive morphological designation for different lymphoma entities in one individual irrespective of clonal relationship. Many types of aggressive B-cell non-Hodgkin's lymphomas and Hodgkin's lymphomas are reported to secondarily develop in lymphoma progression. Genetic changes associated with lymphoma progression frequently abrogate the differentiating effects of alterations occurring in indolent lymphomas, leading to increased cell proliferation. Within different lymphoma entities, high-risk disease variants mimicking lymphoma progression exist. [source]