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Dysregulation of MYC is the genetic hallmark of Burkitt lymphoma (BL) but it is encountered in other aggressive mature B-cell lymphomas. MYC dysregulation needs other cooperating events for BL development. We aimed to characterize these events and assess the differences between adult and paediatric BLs that may explain the different outcomes in these two populations. We analysed patterns of genetic aberrations in a series of 24 BLs: 11 adults and 13 children. We looked for genomic imbalances (copy number variations), copy-neutral loss of heterozygosity (CN-LOH) and mutations in TP53, CDKN2A, ID3 (exon 1), TCF3 (exon17) and CCND3 (exon 6). Young patients displayed more frequent 13q31.3q32.1 amplification, 7q32q36 gain and 5q23.3 CN-LOH, while 17p13 and 18q21.3 CN-LOH were only detected in adult BLs. ID3 mutations were present in all adult samples, but only in 42% of childhood cases. CCND3 and ID3 double-hit mutations, as well as 18q21 CN-LOH, seemed to be associated with poorer outcome. For the first time, we report different genetic anomalies between adult and paediatric BLs, suggesting age-related heterogeneity in Burkitt lymphomagenesis. This may explain the poorer prognosis of adult BLs. Additional studies are needed to confirm these results in the setting of clinical trials.

In an attempt to compare the sensitivity of bone radiographs and bone marrow magnetic resonance (MR) imaging for bone lesion detection in patients with stage III multiple myeloma (MM) and to evaluate the possible consequences of the replacement of the conventional radiographic skeletal survey (RSS) by an MR survey of the spinal and pelvic bone marrow in these patients, we obtained MR studies of the thoracic and lumbar spine, pelvis and proximal femurs in addition to the conventional RSS (including radiographs of the skull, entire spine, pelvis, ribs, humerus and femurs) in 80 consecutive patients with newly diagnosed stage III MM according to the Durie and Salmon staging system (based on blood tests and on the RSS). The performance of MR and radiographic studies to detect bone lesions in given anatomic areas and in given patients were compared. The consequences on MM staging following the substitution of the RSS by the MR survey were assessed. MR imaging was superior to radiographs for lesion detection in the spine (76% v 42% of patients) and pelvis (75% v 46% of patients). The RSS was superior to the limited MR imaging survey for the detection of bone involvement in the patient population (87.5% v 79% of patients). If the RSS had been replaced by the MR imaging survey for patient staging, 7/80 patients would have been categorized as stage I and one as stage II MM on the basis of normal MR findings and biological findings consistent with these stages. Substitution of the RSS by a limited spinal and pelvic marrow MR survey would lead to 'understaging' of 10% of patients with otherwise stage III MM on the basis of blood tests and the conventional RSS.

Bone marrow blood flow has been assessed using positron emission tomography and the 15O-labelled carbon dioxide steady-state technique. The measurements were performed at the site of the posterior iliac crest. The bone marrow blood flow was 10.0 ml/min/100 cm3 +/- 3.0 (SD) in normal volunteers. It was markedly increased in patients with polycythaemia vera (26.9 +/- 4.6), chronic granulocytic leukaemia (25.2 +/- 3.9) and myelofibrosis (35.1 +/- 7.3). However, bone marrow blood flow did not differ from normal in patients with aplastic anaemia, chronic haemolysis or chronic lymphocytic leukaemia. There was no relationship between bone marrow cellularity and bone marrow blood flow. The data show that bone marrow blood flow is markedly elevated in polycythaemia vera, myelofibrosis and chronic granulocytic leukaemia and suggest that bone marrow cellularity is not a major factor in regulating bone marrow blood flow.

Idic(X)(q13) represents a rare but recurrent chromosomal abnormality in haematological malignancies. We present five new cases characterized by this particular aberration and review the literature on this subject. The patients were elderly females with a diagnosis of refractory anaemia (1/5), refractory anaemia with ringed sideroblasts (2/5), chronic myelomonocytic leukaemia (1/5), and Philadelphia chromosome-negative chronic myeloid leukaemia (1/5). Three out of the five patients demonstrated an increased proportion of bone marrow ringed sideroblasts. After a follow-up period of 30-57 months all patients but one are alive. Idic(X)(q13) always occurred as the sole chromosomal abnormality, either in one or in two copies. We confirmed the dicentric nature of the aberration by fluorescence in situ hybridization (FISH) on metaphases as well as interphase nuclei using an X-chromosome-specific alpha-satellite probe, and performed chromosome painting to visualize possible additional chromosomal changes involving the X chromosomes. Our findings and the data of 17 previously published cases indicate that idic(X)(q13): (1) may play a significant pathogenetic role in haematological malignancies affecting exclusively females and deriving predominantly from early progenitor cells; (2) is frequently associated with a pathological iron accumulation; (3) indicates a variable prognosis.

Cold-antibody autoimmune haemolytic anaemia is a rare entity that has been associated with a wide variety of pathological processes, including malignant lymphoproliferative disorders. In this retrospective study we recorded, as far as possible, clinical, haematological, immunological, morphological, pathological, cytogenetic and molecular data on 10 patients with cold agglutinin disease (CAD). Cytogenetic anomalies were found in four cases in which an underlying lymphoma could be evidenced. Trisomy 3 was the only recurrent aberration in our series. It was observed in all patients with abnormal karyotype, either as a complete trisomy or as a partial trisomy of the long arm. The importance of this particular karyotypic aberration in the monitoring of CAD is emphasized.

Chromosomal translocations of the immunoglobulin heavy chain (IgH) gene region at 14q32 are regularly involved in B lymphoid malignancies; they may initiate transformation either by deregulation of existing (proto) oncogenes or creation of new hybrid genes with transforming properties. Previously, we reported a reciprocal novel translocation, t(14;20)(q32;q12), found in the myeloma cell line UM3. In this cell line, the t(14;20) is the only translocation involving the IgH locus. Using double colour immunofluorescence in situ hybridization, the t(14;20) was also found in the diagnostic bone marrow sample, excluding a possible in vitro artefact. We also have found this recurrent t(14;20) in four other cell lines and in additional patient material. We cloned the regions containing the breakpoints in the der(14) and der(20) chromosomes from UM3, and analysed ectopic mRNA expression of genes in the breakpoint regions of both derivative chromosomes. Ectopic gene expression was observed for the transcription factor MAFB in der(14). The breakpoint scatter in the five cell lines with a t(14;20)--all expressing MAFB--is comprised within a region of 0.8 Mb. Provisional data indicate that this t(14;20) is associated with an adverse prognosis. Aberrant expression of MAFB may be involved in the oncogenic transformation of myeloma cells that harbour the t(14;20).

A few cases of secondary neoplasms occurring after treatment with 2-chloro-2'-deoxyadenosine (2CdA) have been reported, mostly in patients previously exposed to other anti-cancer drugs including alkylating agents (AA). Here we report on the occurrence of a myelodysplastic syndrome (MDS) with monosomy 5 and/or 7 in two patients after 2CdA treatment, without or prior to other toxic exposure. In light of a literature review and given the involvement of chromosomes frequently abnormal in secondary leukaemias, we suggest that 2CdA may induce therapy-related MDS (t-MDS).

263 patients (median age 65+/-10 years) with multiple myeloma were treated with cyclophosphamide-prednisone. Out of this cohort, 103 patients had progressive disease and were randomly assigned to either VAD (vincristine, doxorubicin, dexamethasone; 50 cases) or VMBCP (vincristine, BCNU, cyclophosphamide, melphalan and prednisone; 53 cases). There were no statistical differences between the two groups with the respect to clinical, biological and radiological parameters. There was no difference in survival between the VAD and VMBCP groups. The 4 months response rate was similar in the two groups (50% VAD, 56% VMBCP). With multivariate analysis for survival (Cox model), two factors had a statistically significant impact: Karnofsky index (> 60) and albuminaemia ( 60 and albuminaemia > or = 34 g/l, the median survival was 29 months v 2 months with a Karnofsky index < or = 60 and albuminaemia < 34 g/l (P

Marginal zone B-cell lymphoma (MZBCL) represents a distinct subtype of B-cell non-Hodgkin's lymphoma (NHL) which has been recently recognized and defined as a disease entity. Cytogenetically, these lymphomas reveal a high prevalence of trisomy 3, and recent data obtained by comparative genomic hybridization indicate that the chromosomal regions 3q21-23 and 3q25-29 might be of particular pathogenetic significance. We identified structural chromosomal abnormalities involving the region 3q27 and rearrangements of the BCL6 proto-oncogene in three out of 34 (9%) well-defined cases of extranodal, nodal and splenic MZBCL using cytogenetic analysis. Southern blot, and fluorescence in situ hybridization (FISH). All three cases were characterized by a t(3;14)(q27;q32). Two of them showed additional chromosomal abnormalities including trisomy 3, which was found in one case. The patients displayed extranodal disease and did not demonstrate any striking clinical and histological differences when compared with MZBCL lacking BCL6 rearrangement. The present study for the first time demonstrates the occurrence of t(3;14)/BCL6 gene rearrangement in MZBCL, thus suggesting a role of the BCL6 proto-oncogene in the pathogenesis of MZBCL.

Trisomy 3 represents the most frequent and consistent chromosomal abnormality characterizing the recently defined entity marginal zone B-cell lymphoma (MZBCL). By cytogenetic analysis and/or fluorescence in situ hybridization (FISH) on interphase nuclei we found an increased copy number of chromosome 3 in 22/36 (61%) successfully analysed cases, including 8/12 cases with extranodal MZBCL, 8/13 cases with nodal MZBCL, and 6/11 patients with splenic MZBCL. Sensitivity of interphase cytogenetics was somewhat higher than that of conventional cytogenetic investigation, Structural chromosomal changes involving at least one chromosome 3 were seen in 11/20 cases with an increased copy number of chromosome 3: +del(3)(p13) was demonstrated in three cases, and was the sole chromosomal abnormality in one of them: +i(3)(q10) was seen in two other patients; and rearrangements involving various breakpoints on the long arm of chromosome 3 were found in the remaining cases, FISH on metaphase spreads confirmed these structural abnormalities and additionally showed two unexpected translocations involving chromosome 3, We conclude that: (1) trisomy 3 occurs in a high proportion of extranodal, nodal and splenic MZBCL; (2) FISH on interphase nuclei is an additional and sensitive tool in detecting an increased copy number of chromosome 3 in MZBCL; (3) additional structural abnormalities involving the long arm of chromosome 3 are frequent but non-recurrent and are perhaps secondary changes; and (4) abnormalities such as +del(3)(p13) and +i(3)(q10) suggest that genes located on the long arm of chromosome 3 are of particular importance in the pathogenesis of MZBCL.

The PRDM16 (1p36) gene is rearranged in acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS) with t(1;3)(p36;q21), sharing characteristics with AML and MDS with MECOM (3q26.2) translocations. We used fluorescence in situ hybridization to study 39 haematological malignancies with translocations involving PRDM16 to assess the precise breakpoint on 1p36 and the identity of the partner locus. Reverse-transcription polymerase chain reaction (PCR) was performed in selected cases in order to confirm the partner locus. PRDM16 expression studies were performed on bone marrow samples of patients, normal controls and CD34(+) cells using TaqMan real-time quantitative PCR. PRDM16 was rearranged with the RPN1 (3q21) locus in 30 cases and with other loci in nine cases. The diagnosis was AML or MDS in most cases, except for two cases of lymphoid proliferation. We identified novel translocation partners of PRDM16, including the transcription factors ETV6 and IKZF1. Translocations involving PRDM16 lead to its overexpression irrespective of the consequence of the rearrangement (fusion gene or promoter swap). Survival data suggest that patients with AML/MDS and PRDM16 translocations have a poor prognosis despite a simple karyotype and a median age of 65 years. There seems to be an over-representation of late-onset therapy-related myeloid malignancies.

In an attempt to compare the sensitivity of bone radiographs and bone marrow magnetic resonance (MR) imaging for bone lesion detection in patients with stage III multiple myeloma (MM) and to evaluate the possible consequences of the replacement of the conventional radiographic skeletal survey (RSS) by an MR survey of the spinal and pelvic bone marrow in these patients, we obtained MR studies of the thoracic and lumbar spine, pelvis and proximal femurs in addition to the conventional RSS (including radiographs of the skull, entire spine, pelvis, ribs, humerus and femurs) in 80 consecutive patients with newly diagnosed stage III MM according to the Durie and Salmon staging system (based on blood tests and on the RSS). The performance of MR and radiographic studies to detect bone lesions in given anatomic areas and in given patients were compared. The consequences on MM staging following the substitution of the RSS by the MR survey were assessed. MR imaging was superior to radiographs for lesion detection in the spine (76% v 42% of patients) and pelvis (75% v 46% of patients). The RSS was superior to the limited MR imaging survey for the detection of bone involvement in the patient population (87.5% v 79% of patients). If the RSS had been replaced by the MR imaging survey for patient staging, 7/80 patients would have been categorized as stage I and one as stage II MM on the basis of normal MR findings and biological findings consistent with these stages. Substitution of the RSS by a limited spinal and pelvic marrow MR survey would lead to 'understaging' of 10% of patients with otherwise stage III MM on the basis of blood tests and the conventional RSS.

A randomized trial has been performed in which 91 patients with stage III myeloma and additional severe criteria were randomly allocated to either VAD or VMBCP. No significant difference was noted between these two groups using the following criteria: response rate (VMBCP: 54%; VAD: 39%), impact on symptoms, median survival (VMBCP: 14 months, VAD: 17 months). However, toxic effects and refusal to pursue treatment were more frequent with VAD than with VMBCP (12 v 6). Therefore, in this trial, VMBCP appears to be more useful than VAD.

Summary The functional evaluation of ataxia telangiectasia mutated (ATM) and p53 was recently developed in B-cell chronic lymphocytic leukaemia (B-CLL), a disease in which the response to DNA damage is frequently altered. We identified a novel biomarker of chemosensitivity based on the induction of DNA damage by the purine nucleoside analogues (PNA) fludarabine and 2-chlorodeoxyadenosine (CdA). Using genome-wide expression profiling, it was observed that, in chemosensitive samples, PNA predominantly increased the expression of p53-dependent genes, among which PLK2 was the most highly activated at early time points. Conversely, in chemoresistant samples, p53-dependent and PLK2 responses were abolished. Using a quantitative real time polymerase chain reaction, we confirmed that PNA dose- and time-dependently increased PLK2 expression in chemosensitive but not chemoresistant B-CLL samples. Analysis of a larger cohort of B-CLL patients showed that cytotoxicity induced by PNA correlated well with PLK2 mRNA induction. Interestingly, we observed that failure to up-regulate PLK2 following PNA and chemoresistance were not strictly correlated with structural alterations in the TP53 gene. In conclusion, we propose that testing PLK2 activation after a 24-h incubation with PNA could be used to investigate the functional integrity of DNA damage-response pathways in B-CLL cells, and predict clinical sensitivity to these drugs.

Bone marrow samples of 16 patients (two adults and 14 children) with a B lineage acute lymphoblastic leukaemia (ALL), and in whom Ig heavy chain gene rearrangements were detectable at diagnosis using polymerase chain reaction (PCR), were studied during evolution using PCR. The VDJ junctional fragment of the Ig heavy chain rearranged gene was amplified at diagnosis. After length reduction by restriction digestion, the amplified fragment was recovered by chromatography, labelled using a specific hexamer as a primer and directly used as a clonospecific probe. The sensitivity of the PCR ranged from 1:10(4) to 1:10(5) cells, depending on the patient's rearrangement. Residual disease (MRD) was detected in most of the patients achieving a complete remission after induction therapy, regardless of the long-term outcome of treatment. However, in patients remaining in complete remission, the level of MRD showed a tendency to decrease and ultimately become undetectable for variable periods of time, while in patients eventually relapsing there was a trend for MRD to persist at stable levels and even to increase before relapse was clinically evident. We conclude that the use of a simplified methodology for obtaining a clonospecific probe from the Ig heavy chain gene, though less sensitive than the sequencing methodology, is a valuable and readily available tool to monitor MRD in a high proportion of B lineage ALL.

Clonal rearrangements of immunoglobulin heavy chain genes as well as both T cell receptor (TCR) delta and gamma genes were found in four cases of blast crisis of Ph+ chronic myeloid leukaemia with unequivocal B cell precursor (common) immunophenotype. In one case, the TCR beta chain gene was also rearranged. Although the developmental sequence of TCR delta, gamma and beta rearrangements in T lymphocytes appeared to be respected, a full phenotypic effect, characteristic of T cell was not observed in these otherwise typical 'common' blast cells. Cytogenetic analysis ruled out the occurrence of TCR rearrangement due to structural chromosome changes. A high incidence of unexpected TCR gene rearrangements has been previously reported in the de novo 'common' acute lymphoblastic leukaemias (ALL). Our cases of chronic myeloid leukaemia (CML) in lymphoid blast crisis show that genotypic similarities may exist between these two haematological entities.

Clinical and cytogenetic data were analysed in 54 patients with acute non-lymphocytic leukaemias (ANLL) or MDS (myelodysplastic syndromes) and deletion of the long arm of chromosome 7 (7q-), in order to determine if there is a commonly deleted region in 7q and to establish possible correlations between karyotypic features, such as karyotype pattern, karyotype complexity, associated anomalies, and/or the type of deleted segments, and outcome of patients with these disorders. The median follow-up of our patients was 4 months (range 1-89), as was the median survival, In 30% of the cases there was a history of preceding MDS or previous chemotherapy. Clinical and cytogenetic remission was obtained in 7/36 patients treated with chemotherapy (CT). At the time of 7q- detection, three patients previously treated with CT for ANLL. were in clinical remission, 5q- was the most recurrent associated abnormality, Complex karyotypes were observed in 68% of the cases, In univariate analysis, statistical differences in survival were observed according to diagnosis (therapy-related and secondary diseases had a worse prognosis than primary disorders), the chromosomal segments deleted (the loss of band 7q32 was of poor prognostic value), the karyotype complexity (patients with single anomalies did better than patients with complex anomalies) and the response to therapy (patients who achieved complete remission had a better survival probability), In multivariate analysis, the loss of band 7q32 was found to be significantly related to very poor prognosis, This finding suggests that band 7q32 may contain critical genes that should be explored at the molecular level.