Clinical risk scores do not accurately identify a very high risk population with diffuse large B cell lymphoma-an analysis of 386 Portuguese patients.

The identification of high-risk patients deserving alternative first-line treatments to R-CHOP is a research priority in diffuse large B cell lymphoma (DLBCL). Despite the increasing recognition of biological features underlying aggressive behavior, clinical scores remain the basis for prognostic evaluation and treatment stratification in DLBCL. We performed a retrospective analysis of patients with DLBCL uniformly treated with immunochemotherapy with the aim of assessing the discriminative power of the NCCN international prognostic index (IPI) and the GELTAMO-IPI scores in risk group stratification and compared them with the IPI. Additionally, we investigated if bulky disease, gender, beta-2 microglobulin (ß2m), body mass index, and B-symptoms have independent prognostic impact. We confirmed the discriminative ability of the three prognostic scores in terms of progression-free survival and overall survival and found that the NCCN-IPI performs better in the identification of a high-risk population compared to the IPI and the GELTAMO scores. In an attempt to improve the prognostic power of the NCCN-IPI we analyzed additional clinical variables. Bulky disease and elevated ß2m were found to be independent predictors of prognosis when controlling for the NCCN-IPI risk groups. However, they seem to bring no incremental power to the latter in the identification of poor outcome patients. We support the use of the NCCN-IPI for the clinical identification of high-risk patients in DLBCL. Future studies to unravel the biological heterogeneity within NCCN-IPI groups are needed to improve risk prediction and design targeted therapies for poor prognosis patients.

Evaluation of Pax5 expression and comparison with BLA.36 and CD79αcy in feline non-Hodgkin lymphoma.

Paired box gene 5 (Pax5) is a widely used B-cell marker for human and canine non-Hodgkin's lymphoma (nHL); however, in the literature there is only one case report using Pax5 in a cat B-cell lymphoma. The purposes of this study were to investigate the expression and detection of B-cell specific activator protein (BSAP) using a monoclonal anti-Pax5 antibody in feline nHL (FnHL) tissue samples to evaluate its diagnostic relevance as a B-cell marker. A total of 45 FnHL samples in 45 cats were evaluated. B-cell lymphoma was the most common immunophenotype (51.1%) for all the samples and T-cell the most common immunophenotype (64.3%) for the gastrointestinal (GI) form. Pax5 stained 82.6% of all B-cell lymphomas and no expression was found in any of the T-cell lymphomas. Anti-Pax5 antibody staining in FnHL is similar to that reported in human and canine counterparts and may offer an excellent B-cell marker in cats.

Cutaneous Richter syndrome: a better place to transform?

The development of high-grade lymphoma in patients with chronic lymphocytic leukaemia is known as Richter syndrome (RS) and is associated with a grave prognosis, with a mean survival of 8 months despite treatment. Cutaneous RS has been described in a handful of cases and may be associated with a better outcome than the more common extracutaneous variants. We review the literature with particular emphasis on pathogenesis, treatment and survival of RS. We postulate that the absence of B symptoms and a normal lactate dehydrogenase level, presumably reflecting localized or limited disease, and a lower tumour burden, may explain the apparently better survival in some patients with cutaneous RS than with extracutaneous variants.

Cytogenetic abnormalities in MALT lymphomas and their precursor lesions from different organs. A fluorescence in situ hybridization (FISH) study.

AIMS: To analyse the possible activation of distinct molecular pathways in mucosa-associated lymphoid tissue (MALT) lymphoma, we determined the prevalence of trisomies 3, 12, 18 in MALT lymphomas from different organs, as well as the prevalence of translocations of the MALT1 gene in a subset of primary breast MALT lymphomas. We compared the numerical cytogenetic alterations in lymphomas, precursor lesions and in normal non-haematolymphoid tissue from the same organs. METHODS AND RESULTS: Forty-two samples of paraffin-embedded tissue (29 MALT lymphomas from stomach, breast, parotid and thyroid; two Sjögren's syndrome; two Hashimoto's thyroiditis and nine reactive samples) were studied by fluorescence in situ hybridization (FISH). Analysed together, the cases of gastric, parotid and thyroid MALT lymphomas presented trisomy 3 in 46%, trisomy 12 in 28% and trisomy 18 in 21% of the cases. In contrast to other locations, trisomy 3 was not present in the majority of the cases of primary breast MALT lymphomas. None of the nine breast cases presented MALT1 gene rearrangements. Half of the cases of preneoplastic lesions exhibited trisomy 3 and trisomy 12; none exhibited trisomy 18. CONCLUSIONS: Trisomy 3 is the most frequent numerical abnormality in gastric, parotid and thyroid but not in primary breast MALT lymphomas. MALT1 gene rearrangements are also rare in this location, suggesting that distinct molecular pathways may be activated in breast cases.

Significantly improved PCR-based clonality testing in B-cell malignancies by use of multiple immunoglobulin gene targets. Report of the BIOMED-2 Concerted Action BHM4-CT98-3936.

Polymerase chain reaction (PCR) assessment of clonal immunoglobulin (Ig) and T-cell receptor (TCR) gene rearrangements is an important diagnostic tool in mature B-cell neoplasms. However, lack of standardized PCR protocols resulting in a high level of false negativity has hampered comparability of data in previous clonality studies. In order to address these problems, 22 European laboratories investigated the Ig/TCR rearrangement patterns as well as t(14;18) and t(11;14) translocations of 369 B-cell malignancies belonging to five WHO-defined entities using the standardized BIOMED-2 multiplex PCR tubes accompanied by international pathology panel review. B-cell clonality was detected by combined use of the IGH and IGK multiplex PCR assays in all 260 definitive cases of B-cell chronic lymphocytic leukemia (n=56), mantle cell lymphoma (n=54), marginal zone lymphoma (n=41) and follicular lymphoma (n=109). Two of 109 cases of diffuse large B-cell lymphoma showed no detectable clonal marker. The use of these techniques to assign cell lineage should be treated with caution as additional clonal TCR gene rearrangements were frequently detected in all disease categories. Our study indicates that the BIOMED-2 multiplex PCR assays provide a powerful strategy for clonality assessment in B-cell malignancies resulting in high Ig clonality detection rates particularly when IGH and IGK strategies are combined.

Improved reliability of lymphoma diagnostics via PCR-based clonality testing: report of the BIOMED-2 Concerted Action BHM4-CT98-3936.

The diagnosis of malignant lymphoma is a recognized difficult area in histopathology. Therefore, detection of clonality in a suspected lymphoproliferation is a valuable diagnostic criterion. We have developed primer sets for the detection of rearrangements in the B- and T-cell receptor genes as reliable tools for clonality assessment in lymphoproliferations suspected for lymphoma. In this issue of Leukemia, the participants of the BIOMED-2 Concerted Action CT98-3936 report on the validation of the newly developed clonality assays in various disease entities. Clonality was detected in 99% of all B-cell malignancies and in 94% of all T-cell malignancies, whereas the great majority of reactive lesions showed polyclonality. The combined BIOMED-2 results are summarized in a guideline, which can now be implemented in routine lymphoma diagnostics. The use of this standardized approach in patients with a suspect lymphoproliferation will result in improved diagnosis of malignant lymphoma.

Intravascular large B-cell lymphoma of the breast.

The case of an 80-year-old woman with symmetrical breast engorgement and nonspecific systemic symptoms progressively developing over 3 months and confirmed on surgical biopsy to be due to an intravascular large B-cell lymphoma (ILBCL) is presented. To our knowledge, ILBCL has never been reported in the breast before and its mammography and ultrasound appearances are described.

Treatment of gastric MALT lymphoma by Helicobacter pylori eradication: a study controlled by endoscopic ultrasonography.

OBJECTIVE: Previous studies have demonstrated a link between Helicobacter pylori infection and low grade B-cell gastric MALT lymphoma. The aim of this study was to evaluate the effect of Helicobacter pylori eradication in 17 patients with low grade B-cell gastric MALT lymphoma stage EI. METHODS: For disease staging EUS and CT scan were systematically performed. Eight patients were excluded from the present series because stage EII disease was diagnosed. To demonstrate B-cell monoclonality, immunohistochemistry and polymerase chain reaction were used. H. pylori eradication was performed with triple therapy. RESULTS: H. pylori was eradicated in all patients after first (n = 15) or second line (n = 2) treatment. Histologic regression of lymphoma was observed in all patients after a median period of 2 mo. Disappearance of monoclonality according to polymerase chain reaction took significantly longer (7 mo). At the end of the study, four of 16 patients still exhibited persistent monoclonal bands. Relapse of lymphoma occurred in two patients associated with H. pylori reinfection/recrudescence. CONCLUSION: Eradication of H. pylori seems to be an effective therapy in patients with stage EI gastric MALT lymphoma, although long-term results are still uncertain. Endoscopic ultrasonography is useful for a more accurate staging of the disease. The clinical significance of detecting monoclonality by polymerase chain reaction remains to be determined.

Differential expression of cell adhesion molecules in the functional compartments of lymph nodes and tonsils.

Aims-To analyse the topographical distribution of adhesion molecules involved in lymphocyte recirculation in human lymph nodes and tonsils. The study focused on the expression of LECAM-1 (CD62L), VLA-alpha4 (CD49d), VLA-beta1 (CD29), LFA-1 alphaL (CD11a), LFA-beta2 (CD18), VCAM-1 (CD106), ICAM-1 (CD54), and H-CAM (CD44).Methods-Reactive lymph nodes and palatine tonsils were studied using immunofluorescence methods with fluorescein isothiocyanate (FITC) labelled monoclonal antibodies directed against cell adhesion molecules. To investigate the expression patterns of these molecules in the T and B cell populations, double labelling experiments were performed using Texas Red labelled antibodies against CD2 or CD19, respectively. The images from each fluorochrome were then simultaneously analysed using a laser scanning confocal microscope.Results-LECAM-1, VLA-alpha4 and H-CAM were predominantly expressed by mantle zone B cells, VCAM-1 and ICAM-1 by germinal centre cells, most of which exhibited a reticular staining pattern suggestive of follicular dendritic cells, whereas LFA-1 alphaL and LFA-beta2 were mainly found in extrafollicular and germinal centre T cells. All high endothelial venules expressed VLA-beta1 and ICAM-1, whereas VCAM-1 was present in only a few, with variable intensity.Conclusions-The data show that all of these adhesion molecules are differentially distributed within the distinct functional microenvironments of both organs. The differences observed in the expression patterns among the B and T cells belonging to different compartments probably depend on the momentum of cell traffic, the stage of maturation/activation, as well as on their functional role in the immune response.

Mycosis fungoides with early central nervous system involvement.

The authors present a rare case of mycosis fungoides with early central nervous system involvement mimicking an intramedullary tumour in a 38- year-old white male.

Phenotyping of T-cell lymphomas in paraffin sections--which antibodies?

Five antibodies, MT1 (CD43), UCHL1 (CD45RO), OPD4, poly-CD3 and beta F1, were assessed for their reactivity with 50 archival cases of T-cell lymphoma in formalin-fixed paraffin-embedded tissue. All cases had been previously characterized as T-cell lymphomas, and the histological types included 14 cases of small cerebriform lymphoma, six cases of angioimmunoblastic lymphadenopathy-like T-cell lymphoma, four cases of T-zone lymphoma, five cases of pleomorphic small cell lymphoma, 12 cases of pleomorphic medium and large cell lymphoma, four cases of anaplastic large cell lymphoma, two cases of T-lymphoblastic lymphoma and three cases of enteropathy-associated T-cell lymphoma. UCHL1 and MT1 showed reactivity with the highest percentage of cases (94 and 86% respectively) but lack absolute specificity for T-cells, especially in high-grade lymphomas. Poly-CD3 is highly specific for T-cells, and stained neoplastic cells in almost 80% of the cases. beta F1 stained the lowest percentage of cases (40%). UCHL1 and poly-CD3 together identified 98% of cases, and this combination is recommended for the diagnosis of T-cell lymphomas in paraffin sections.