Two patterns of chromosomal breakpoint locations on the immunoglobulin heavy-chain locus in B-cell lymphomas with t(3;14)(q27;q32): relevance to histology.

The t(3;14)(q27;q32) is the most common translocation involving BCL6 in B-cell lymphoma. Although this translocation was predominantly associated with diffuse large B-cell lymphoma (DLBCL), recent studies have shown that it can also be found in follicular lymphomas (FL), often associated with a large cell component. To further investigate the relationship that might exist between this translocation and the phenotype of the tumors, we studied 34 lymphomas with a t(3;14)(q27;q32). Twenty cases were DLBCL, 14 FL and most cases, regardless of histology, were negative for the expression of CD10 (26/32, 81%). We identified the IGH switch region involved in the translocation for 32 cases. Our data indicate that in DLBCL most breakpoints involve the switch mu (17/19; 89%), whereas in FL most involve a switch gamma (9/13; 70%) (P=0.0016, Fisher's exact test). This correlation between the histology and the structure of the translocated allele suggests that the lymphomas with Smu and Sgamma translocations may originate from different cells, or that the substituted regulatory regions that come to deregulate BCL6 may affect the presentation of the disease.

Clinical and biological relevance of single-nucleotide polymorphisms and acquired somatic mutations of the BCL6 first intron in follicular lymphoma.

Genetic modifications of the BCL6 gene in lymphoma include translocations, deletions, and somatic mutations (SM) of the 5' noncoding region. Three single-nucleotide polymorphisms (SNPs) of the major mutation cluster region (MMC) have been reported, including two substitutions (397G/C, 502G/A) and one deletion (520DeltaT). Clinical and biological relevance of these SNPs are unknown. Based on a case-control study, BCL6 SNPs frequencies were assessed in 97 t(14;18) follicular lymphomas (FL) and in 54 lymphomas with 3q27 rearrangement. Allele frequencies were similar in the FL and controls groups. The 397 G/C genotype was correlated to a higher-grade transformation risk (P=0.02). SM were observed in 39.1% of FL and were characterized by a clustering distribution (hot spots spanning position 420-435, 106-127, and 590-600). No correlation between genotypes or acquired mutational status and BCL6 expression was demonstrated. However, gel mobility-shift assays, using SNPs containing probes show results representative for protein/DNA complexes. This study demonstrates that the first BCL6 intron is a highly variable region as a consequence of both SNP and SM, which may contribute to biology and outcome of FL.

[Agranulocytosis related to fluindione: A case report]. / Agranulocytose à la fluindione: à propos d'un cas.

INTRODUCTION: While in most countries warfarin is the preferred anti-vitamin K, fluindione, a molecule with a prolonged half-life remains largely prescribed in France. Some of its side effects, including immuno-allergic complications, remain poorly understood. CASE REPORT: A 77-year-old woman presented with a febrile severe neutropenia of immunoallergic mechanism with a favourable outcome associated with fluindione, introduced 25 days earlier for the treatment of atrial fibrillation. CONCLUSION: This rare side effect is a reminder of the importance of biological monitoring in the first weeks following the introduction of fluindione and key diagnostic elements and therapeutic aspects of iatrogenic agranulocytosis.

De novo acute B cell leukemia/lymphoma with t(14;18).

The t(14;18)(q32;q21) translocation is the most common translocation in B cell malignancies being found in 80% of follicular lymphomas and about 20% of diffuse large B cell lymphomas. Only rare cases of de novo acute B cell lymphoblastic leukemia with t(14;18) have been described. We describe five cases of this entity which appears to have very homogeneous clinical, phenotypic and genotypic features. None of these patients had prior history of follicular lymphoma. The disease was characterized by acute clinical features with nodal and/or extranodal disease, massive bone marrow infiltration and rapid increase of circulating blast cells of mature B cell phenotype. All patients disclosed complex chromosomal and molecular abnormalities involving at least the BCL-2 and c-MYC genes. Furthermore, three patients had evidence of BCL-6 involvement and one patient had a p53 mutation. Despite intensive chemotherapy, including for two patients allogeneic bone marrow transplantation in first complete remission, all patients died within a few months. Neuro-meningeal relapse occurred in three of the five patients in spite of neuro-meningeal prophylaxis. De novo leukemia/lymphoma with t(14;18) is a rare entity with a very poor prognosis. Whether early bone marrow transplant could modify the natural history of the disease remains to be determined. An intensive neuro-meningeal prophylaxis appears to be mandatory in these patients.

Characterisation of BCL2-JH rearrangements in follicular lymphoma: PCR detection of 3' BCL2 breakpoints and evidence of a new cluster.

Follicular lymphomas (FL) are closely associated with a t(14;18)(q32;q21) translocation, leading to a bcl2 protein over-production. This translocation probably constitutes a very early step in the development of the disease. Besides the cytogenetic assay, t(14;18) detection can be achieved using either Southern blot or polymerase chain reaction (PCR). Since 1990, several publications have reported discrepancies between the results of cytogenetic and molecular analysis of t(14;18). Using methods able to explore long DNA fragments, several authors reported breakpoints located outside the usual breakpoint regions. However, these techniques cannot be easily used in routine. The aim of this study was to develop a simple PCR assay to amplify rearrangements usually not detected in FL. We selected a group of 83 patients with a t(14;18) on cytogenetic analysis: using usual probes and primers, 54/83 (65.1%) showed a MBR rearrangement, 7/83 (8.4%) were mcr positive and 22/83 (26.5%) remained negative. Among these 22 rearrangements, nine could be detected using this new PCR assay. Four breakpoints were located in a 20 bp area suggesting a recurrent breakpoint cluster close to an Alu repetitive sequence. Finally, remaining negative cases (13/83, 15.6%) suggest that other breakpoints are located between the MBR and mcr regions.

Follicular lymphoma without t(14;18) and with BCL-6 rearrangement: a lymphoma subtype with distinct pathological, molecular and clinical characteristics.

Translocations involving the BCL-6 gene are frequently observed in diffuse large B cell lymphoma, but have rarely been reported in follicular lymphoma (FL). We studied a distinct cohort of FLs with a 3q27/BCL-6 gene rearrangement, but lacking the t(14;18) translocation. In 13/15 cases, translocations involved the 3q27 and the 14q32 regions. All cases displayed a marked follicular growth pattern and, in some instances, a monocytoid component. Tumor cells were CD5(-) CD20(+) CD23(-) CD43(-) BCL-6(+), and in the main CD10 negative (n = 10, 71%) and BCL-2 negative (n = 11, 78%). When compared to 20 typical t(14;18)(+) FLs, the presence of large follicles (P = 0.01) and a CD10(-)/BCL-2(-) phenotype were more frequently observed (P = 0.001) in our cohort. Clonal mutations arising in the BCL-6 first intron were observed in 5/7 cases with evidence of intraclonal heterogeneity, consistent with a germinal center origin. No significant difference was found in comparison to t(14;18)(+) FL regarding age, sex, performance status, bone marrow involvement or overall survival. However, in the 3q27(+) FL group, a stage III/IV disease and a bulky mass were less frequently observed. This study indicates that 3q27(+) FL without t(14;18) translocation have peculiar clinico-pathologic features and may correspond to a rare and distinct subtype of lymphoma originating from the germinal center.

Distribution of BCL2 breakpoints in follicular lymphoma and correlation with clinical features: specific subtypes or same disease?

The t(14;18)(q32;q21) translocation is closely associated with follicular lymphoma (FL), and is routinely assessed with molecular methods exploring BCL2 breakpoints for both diagnosis and minimal residual disease (MRD) monitoring. We and others have previously reported new recurrent breakpoints (3'BCL2 and 5'mcr) which could be easily analyzed. In this study, we characterized the BCL2 breakpoints in 113 untreated patients with t(14;18)-positive FL and correlated their location with the location of JH break and with the clinical features. Breakpoints were respectively located at the major breakpoint region (MBR) in 73 cases (65%), at the minor cluster region (mcr) in 10 cases (9%), at 3'BCL2 in 14 cases (12%) and at 5'mcr in seven cases (6%). Finally, the breakpoint could not be located in nine patients (8%). 5'mcr cases were associated with bulky and high-stage disease, with frequent extranodal involvement and bone marrow infiltration. Survival studies did not show any correlation between breakpoint location and clinical outcome. The joining JH6 segment was the most frequently involved whatever the breakpoint location. In conclusion, unusual BCL2 breakpoints are found in about 20% of newly diagnosed follicular lymphomas and their study should be considered in the investigation of BCL2-JH rearrangement. It was not possible, in this series, to demonstrate any correlation between breakpoint location and either initial characteristics of the disease or survival of the patients.

Follicle center lymphoma is associated with significantly elevated levels of BCL-6 expression among lymphoma subtypes, independent of chromosome 3q27 rearrangements.

The BCL-6 gene, located on chromosome 3q27, is implicated in the normal germinal center formation and is frequently rearranged in a wide spectrum of lymphomas. However the links between genetic alterations and expression of the gene are not clearly determined. We established a quantitative RT-PCR assay based on TaqMan technology to quantify BCL-6 mRNA expression in different subtypes of lymphomas and to compare the level of expression in lymphomas characterized by the presence or absence of BCL-6 translocation. Total RNA was extracted from 105 nodes biopsies (35 diffuse large B cell lymphomas (DLBCL); 26 follicle center lymphomas (FCL); 7 marginal zone lymphomas (MZL); 6 mantle cell lymphomas (MCL); 6 chronic lymphocytic leukemia (CLL); 5 T cell lymphomas (TCL); 7 classical Hodgkin diseases (HD); 6 nodal metastasis (NM); and 7 reactive hyperplasia (RH)). BCL-6 gene rearrangement was assessed by Southern blot analysis in 75% of 3q27(+) DLBCL (n = 20) cases and 67% of 3q27(+) cases (n = 10). The highest level of relative BCL-6 expression was observed in FCL (9.12 +/- 7.28) comparatively to the other lymphoma subtypes including DLBCL (2.53 +/- 1.82; P < 0.001), MCL (1.23 +/- 0.73), MZL (1.49 +/- 1.3), HD (1.60 +/- 1.00), TCL (1.75 +/- 1.64), but also RH (3.91 +/- 3.12) or NM (1.95 +/- 2.6). Among the 26 FCL cases, we observed a lower expression in grade 3 (n = 8) than in grade 1/2 (P < 0.001). Conversely, we failed to show any difference between 3q27(+) DLBCL and 3q27(-)DLBCL cases (P = 0.42). Paradoxically BCL-6 expression in 3q27(+) FCL (n = 10) was significantly lower than in 3q27(-) FCL cases (P = 0.035). Finally, this study showed that BCL-6 expression in lymphoma is largely independent of chromosome 3q27 rearrangement and is more related to the histological subtype. Clinical implication and alternative deregulation pathways of BCL-6 expression remain to be determined.

Peripheral blood stem cell transplantation for relapsed or refractory aggressive lymphoma in patients over 60 years of age.

Intensive chemotherapy with autologous bone marrow transplantation is now considered the treatment of choice for young patients with sensitive relapse of non-Hodgkin's lymphoma (NHL) but results of this procedure in older patients remain unknown. We evaluated the feasibility of two cycles of salvage therapy followed by an autologous peripheral blood stem cell (PBSC) transplantation in 13 patients aged more than 60 years (median age: 62; range 61-72) suffering from relapsed (n = 10) or refractory (n = 3) aggressive NHL. All patients had previously received first-line treatment containing doxorubicin. An association of ifosfamide, VP16, cytosine-arabinoside with or without high-dose methotrexate was used as salvage and priming therapy prior to collection of PBSC. All patients received G-CSF following salvage therapy. PBSC collection could be performed in 10 patients and yielded a median number of CFU-GM: 98.4 x 10(4)/kg (range 68-369). Nine patients underwent a transplantation using BEAM conditioning regimen. The median time to granulocyte and platelet recovery was 13 days (range respectively: 9-25 and 9-16). One patient died from sepsis after transplantation. The main adverse experience occurring after transplantation was a prolonged decline of performance status. Seven patients achieved a complete remission and one failed to respond. Three patients are still alive in CR. We conclude that PBSC collection was possible in selected patients over 60 years of age with refractory or relapsed aggressive NHL and myeloablative therapy could be used with tolerable toxicity. Hematologic recovery and organ toxicity appears to be similar to those observed in younger patients. Deterioration of performance status after transplantation is the most important factor that could limit this procedure. Further investigations are necessary to determine which patients will be able to benefit by this procedure in terms of survival and quality of life.

FISH analysis with a YAC probe improves detection of LAZ3/BCL6 rearrangement in non-Hodgkin's lymphoma.

INTRODUCTION: Chromosomal translocations involving the chromosome 3q27 region are common in B-cell non-Hodgkin's lymphoma (NHL), mainly diffuse large cell lymphoma (DLCL) and less often in follicular lymphoma. Most of these rearrangements involve the same major translocation cluster (MTC) on the 3q27 region, disrupting the LAZ3/BCL6 gene. Some of those translocations are difficult to detect by cytogenetic analysis and/or Southern-blot analysis. In the present report we used a FISH assay to improve the detection of LAZ3/BCL6 rearrangements. METHODS: We isolated a YAC clone (803g3), containing the BCL6 gene, in order to analyze by FISH 19 cases of B-cell non-Hodgkin's lymphoma with cytogenetically detectable 3q27 rearrangement, including reciprocal translocation in 11 cases, deletion in two cases, and addition of undefined chromosomal material on 3q27 in six cases. RESULTS: In the 11 cases with reciprocal translocation, FISH results confirmed cytogenetic data and showed disruption of the LAZ3 region: four t(3;4)(q27;p13), two t(3;11)(q27;q23.1), four t(3;14)(q27;q32) and one t(2;3)(p12;q27). In two of the cases, reciprocal t(3;14) was associated with other cytogenetically detectable abnormalities of 3q27, but FISH showed that they did not affect the LAZ3 gene region. FISH demonstrated a reciprocal translocation with LAZ3 gene rearrangement in two of the six patients with add 3q27: one t(3;11) and one t(3;14). In the two patients with del(3q27), one had two 3q27 FISH signals and one had only one 3q27 FISH signal, but no LAZ3 gene rearrangement was observed. CONCLUSION: We have identified a YAC containing the LAZ3/BCL6 gene. This YAC probe could be useful in clinical practice to demonstrate LAZ3 rearrangements by FISH analysis on tumor samples in NHL.

Chromosome abnormalities in peripheral T-cell lymphoma.

Data on chromosomal abnormalities in T-cell lymphomas are very rare as compared with those reported in B-cell lymphomas. We performed a cytogenetic study in 71 untreated patients with peripheral T-cell lymphoma, classified according to the criteria of the REAL classification. Fifty-seven patients (80.3%) had abnormal clones, whereas 9 karyotypes (12.7%) showed only normal metaphases; 5 karyotypes (7%) could not be analyzed. Recurrent numerical chromosomal abnormalities comprised +3 (21%), +5 (15.7%), +7 (15.5%), +21 (14%), -13 (14%), +8 (12.2%), +19 (12.2%), -10 (10.5%), and -Y (9% of male patients). Chromosomes involved in structural rearrangements were chromosome 6 (31.5%), mainly due to 6q deletions (19.2%), 1q (22.8%), 7q (22.8%), 9p (19.4%), 9q (19.2%), 4q (19.2%), 3q (19.2%), 2p (17.5%), 1p (17.5%), and 14q (17%). Trisomies 3 and 5 mainly correlated with angioimmunoblastic T-cell lymphoma. Isochromosome 7q, associated with trisomy 8, was present in two cases of hepatosplenic gamma/delta T-cell lymphoma. Rearrangements involving the location of T-cell receptor genes were rarely observed (chromosome band 7q35 was rearranged only in three cases, 14q11 in two cases, and 7p15 in none). No correlation could be found between the cytogenetic findings and histologic subgroup or clinical outcome in these patients. Further studies are needed to understand the significance of these abnormalities in peripheral T-cell lymphoma, and to reach a better evaluation of histologic correlations, as many differences persist between the two major classification systems, KIEL and REAL.

Transient anti rhesus alloantibody produced by graft after non-myeloablative allogeneic stem cell transplant.

BACKGROUND: We report the case of a patient who received an allogeneic transplant with peripheral blood compatible ABO, Rhesus mismatched progenitor cells and who developed an asymptomatic transient anti Rhesus alloimmunisation. CASE REPORT: A 56-year-old man with renal cell carcinoma received a non-myeloablative allogeneic PBPC ABO compatible graft from his HLA-identical brother. Graft-versus-host disease prophylaxis consisted of cyclosporine alone. On day + 59, prior to any transfusion, a positive direct antiglobulin test (IgG++, C3d-) was detected. The indirect antiglobulin test (IAT) was considered doubtful, and IAT identification revealed the presence of an active anti Rhesus antibody (anti D specificity) in the patient's serum. This immunisation had no clinical consequence, with no acute hemolytic episode. Further monitoring showed negative antibody screening tests on day + 78. CONCLUSION: To our knowledge this is the first reported case of transient anti Rh (D) allo-immunisation after non-myeloablative allogeneic peripheral blood progenitor cell (PBPC) transplant. The period of occurrence and the specificity of this antibody strongly suggest a donor cell origin.

Double relapse of incomplete form of thrombotic thrombocytopenic purpura.

BACKGROUND: Although several etiologies can be identified in thrombotic thrompocytopenic purpura (TTP), idiopathic cases are still frequent. Incomplete forms are rare and the diagnosis should be suspected in case of thrombocytopenia and microangiopathic haemolytic anaemia. Relapses are frequent in the complete classic form but rarely reported in incomplete forms. According to the literature, mortality and morbidity are significantly improved with plasma exchange (PE). Nevertheless, the management and treatment of relapses remain problematic. CASE REPORT: A 35-year-old woman presented with a double relapse of an incomplete TTP form in the second (24 months) and the fourth year (40 months) after the initial episode. The patient underwent plasma infusion, PE, and was then started on corticosteroids. She also received antiplatelet agents. The main biological indicators were platelet count, haematocrit, lactate dehydrogenase level and schistocytes. Following this treatment, the patient's condition rapidly improved. CONCLUSION: In this incomplete form of TTP, two relapses occurred, with the same presentation. Standard therapy was effective in this case.

[Primary pleural lymphoma after collapse therapy: modern aspects of an historic disease]. / Lymphomes pleuraux primitifs après collapsothérapie: aspects modernes d'une maladie historique.

INTRODUCTION: Pleural lymphomas after long standing pyothorax due to pulmonary tuberculosis are now well identified. Most cases have been described by Japanese investigators and it seems rare or unrecognised in Western countries. We report the study of six cases observed in a single institution. PATIENTS AND METHODS: Six pyothorax-associated pleural lymphomas, among 1,038 lymphoma (0.6%) collected during a period from 1989 to 1998, are described. Diagnosis was established by two pathologists with the usual histologic and immunohistochemical methods, according to the working formulation. The in situ hybridization method for Epstein-Barr virus was performed. RESULTS: The average age of the patient was 73 years. Presenting symptoms combined chest pain and constitutional symptoms more than 45 years after artificial pneumothorax or tuberculous pleuritis. Computerized tomography revealed a pleural mass which involved the adjacent chest wall. Open biopsy by thoracotomy show a diffuse B-cell non-Hodgkin-lymphoma in all cases. Though the lymphoma was initially localized, many poor prognostic factors (age, performance status, LDH, histology) explain the pejorative evolution (average survival of five months). Patients died from an uncontrolled tumoral proliferation or by infectious complications. In situ hybridization confirms the presence of Epstein-Barr virus in tumoral cells. CONCLUSION: Pleural lymphoma is an established complication of artificial pneumothorax. Even if the Epstein-Barr virus plays a crucial role in the pathogenesis, and despite the number of artificial pneumothorax operations that have been widely performed, this lymphoma remains rare, suggesting additional oncogenic factors.

The new haematology analyzer DxH 800: an evaluation of the analytical performances and leucocyte flags, comparison with the LH 755.

INTRODUCTION: The analytical performance and the abnormality messages on differential (flags) of the new analyzer Beckman Coulter DxH 800 were compared with those of the LH 755. METHODS: First, we evaluated the accuracy of the results of the DxH 800, in comparison with the LH 755, in 125 samples without alarm using unflagged sample results on both analyzers. Second, flagged samples on the LH 755 but not flagged by the DxH 800 were evaluated by flow cytometry for accuracy of the DxH 800 results. Finally, we evaluated the sensitivity and specificity of abnormality messages on differential given by the analyzers, in comparison with manual blood smears. RESULTS: The correlation coefficients (R) for complete blood count parameters and differential demonstrated that the DxH 800 results were similar to that of LH 755. Excellent correlation coefficients between DxH 800 and flow cytometry results were found for white blood cell count (R = 0.985, n = 31), platelet count (R = 0.976, n = 51) and nucleated red blood cells (R = 0.966, n = 37). The overall performance showed an increased sensitivity (0.892) and specificity (0.864) of the flags on DxH 800 when compared to the LH 755 (0.846 and 0.733, respectively). CONCLUSION: The DxH 800 provides reliable results and increases laboratory efficiency by reducing working time and costs associated with the optical validation of the results.

Lymphocyte volume and conductivity indices of the haematology analyser Coulter GEN.S in lymphoproliferative disorders and viral diseases.

The haematology analyser Coulter GEN.S gives a set of data -'positional parameters'- defining white blood cell (WBC) populations by mean of index values (mean and standard deviation of volume, conductivity and scatter, used to identify the WBC populations). The volume and conductivity parameters related to the lymphocytes were analysed at diagnosis in patients suffering from chronic B-lymphocytic leukaemia (B-CLL), other non-CLL lymphoproliferative disorders (OLPD) and viral diseases. The standard deviation of volume index (SDVI) is significantly higher in the three groups, whereas the mean volume index (MVI) is significantly lower in B-CLL, and increased in OLPD and viral diseases. These two groups could be distinguished by their mean conductivity index (MCI), which is significantly lower in viral disease group. Cut-offs were calculated for each parameter by the mean of Receiver Operating Characteristic (ROC) analysis. The study of the detection performances showed that the combination of lymphocyte count with SDVI, MVI and MCI could be used with a good sensitivity and specificity to discriminate between the most frequent lymphocyte pathologies, even in patients with normal lymphocyte count.

Difficulties in the management of an incomplete form of refractory thrombotic thrombocytopenic purpura, the usefulness of vincristine.

BACKGROUND: Although several etiologies can be identified in thrombotic thrombocytopenic purpura (TTP), idiopathic cases are still frequent. Incomplete forms are more rare. Currently, the diagnosis may be made in cases of thrombocytopenia and microangiopathic hemolytic anemia. According to the literature, mortality and morbidity are significantly improved with plasma exchange. However, treatment in refractory forms remains problematic. CASE REPORT: A 33-year old woman presented with an incomplete form of TTP, refractory to a combination of therapeutics. The patient underwent plasma infusion, plasma exchange, and then was started on corticosteroids. She also received intravenous immunoglobulins and antiplatelet agents in close proximity to vincristine (Oncovin) infusion. The main biological indicators used were the platelet count, hematocrit, LDH, and the presence of schistocytes. Following vincristine treatment, the patient's condition rapidly improved. CONCLUSION: Vincristine administered after the failure of standard therapeutics was effective in this refractory form of TTP.