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High-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements (DH/TH-HGBL) still miss an in-depth genomic characterization. To identify accompanying genetic events, we performed a pilot study on 7 cases by applying DNA microarray and targeted NGS sequencing. Interestingly, the genetic background of DH/TH-HGBL is largely overlapping with that of other high-grade/poor prognosis lymphomas. Namely, copy number abnormalities were trisomy of chromosome 7 and chromosome 8q gain, encompassing MYC . Among gene variants, those affecting transcription factors ( MYC, FOXO1 ), epigenetic modulators ( KMT2D , EZH2 and CREEBP ), and anti-apoptotic gene ( BCL2 ), were recurrent. MYC and BCL2 were mutated in 3 and 5 cases, respectively. In addition, mutations of FOXO1, previously reported in Diffuse Large B-Cell Lymphomas, were also detected. Clarifying the genomic background of this subset of high-risk lymphomas will pave the way for the clinical use of new biomarkers to: (1) monitor treatment response and; (2) consider alternative targeted therapies.

We retrospectively analyzed the data of 337 patients with cytogenetically normal (CN) acute myeloid leukemia (AML), aged ≤ 65 years (training set). A prognostic index score (PIS) was calculated by totaling the score derived from the regression coefficients of each clinical variable, significantly associated with prognosis by multivariate analysis. The variables that were independent prognostic factors for event-free survival (EFS) and overall survival (OS) in the training set were: age ≥ 50 years, secondary AML and white blood cell count (WBC) ≥ 20 × 10(9)/L. The patients of the training set were stratified into three groups: low-, intermediate- and high-risk. The median EFS was 25, 12 and 7 months in the low-, intermediate- and high-risk groups (p < 0.0001), respectively. The median OS was not reached in the low-risk group and was 19 and 10 months in the intermediate- and high-risk groups (p < 0.0001). This PIS was validated in a series of 193 patients with CN-AML. The median EFS was 66, 16, and 3 months (p < 0.0001) and the median OS was 66, 16, and 5 months in the three risk groups, respectively (p < 0.0001). This PIS may be useful for clinical decision-making in CN-AML and may be prospectively integrated with the newest biological markers which at present are not routinely assessed and need prognostic validation.

Endomyocardial fibrosis (Loeffler's endocarditis) is the main cause of poor outcome in Hyper Eosinophilic Syndrome (HES) and Eosinophilic Leukemia (EL). Reversion of the cardiac damage has been seldom reported, and thrombi can superimpose on infiltrated walls, originating oembolic complications. The tyrosine kynase inhibitor imatinib has been recently employed in patients affected by HES or EL, with impressive results. We have treated with imatinib a young patient affected by Loeffler's endocarditis during EL. Loeffler's endocarditis was studied by transthoracic Doppler echocardiography with and without the contrast agent SonoVue. Cytogenetics, FISH and molecular analysis showed the presence of the FIP1L1/PDGFRA fusion gene, recently detected in a majority of HES patients. Standard echocardiography revealed a large infiltration of the apical region, with apparently pedunculate corpora floating in the LV chamber; after SonoVue injection, a thick endo-myocardial infiltration involving papillary muscles and tendinous chords appeared, which simulated mobile thrombi at standard echography. Treatment with low dose imatinib caused rapid regression of both eosinophilic proliferation and endomyocardiopathy. The fusion gene FIP1L1-PDGFRA was found significantly decreased after a few months of treatment. Using a contrast echocardiographic approach, we demonstrated the non-thrombotic origin of the "in plus" image in our patient and its rapid resolution following imatinib treatment. Imatinib is an excellent candidate for first line treatment of Loeffler's endocarditis, especially when the FIP1L1/PDGFA fusion gene is detected.

Chromosomal abnormalities involving the short arm of chromosome 12 have been frequently observed in a broad spectrum of hematological malignancies. Recently, a gene located in this chromosomal region and implicated in leukemogenesis was identified. The gene, called ETV6 (previously known as TEL) is a new member of the ETS family, a group of genes thought to act as transcriptional activators. The gene spans 240 kb and consists of eight exons coding for a helix-loop-helix (HLH) and a DNA-binding domain. ETV6 was originally identified in a t(5;12)(q33;p13) occurring in a chronic myelomonocytic leukemia (CMML). Recent reports, however, show its involvement in a growing number of translocations associated with myeloid as well as lymphoid leukemias. At the molecular level fusions of ETV6 with PDGFRB (5q33), ABL (9q34), MNI(22q11) and AML1(21q22) have already been identified. Analysis of these chimeric proteins indicates that distinct domains of ETV6 can be involved in different fusion products, thus ETV6 can provide transcriptional and dimerization properties for partner genes, or the gene itself can act as an altered transcriptional factor. At least two clinico-pathological entities associated with ETV6 rearrangements have emerged as distinct disorders. The first one is a chronic myeloid malignancy characterized by t(5;12)(q33;p13), monocytosis and/or eosinophilia. The second entity is a type of childhood acute lymphoblastic leukemia (ALL) hallmarked by t(12;21)(p13;q22), and is shown to be the most frequent but cytogenetically largely undetectable chromosomal anomaly in childhood ALL.

Two new cases of t(8;16)(p11;p13) in acute nonlymphocytic leukemia (ANLL) are described. These two patients in addition to the 34 previously described, showed a striking association with myelomonocytic (M4) or monocytic (M5) leukemia, extramedullary infiltration, erythrophagocytosis and disseminated intravascular coagulation. One of our patients showed a TCRbeta gene rearrangement. Alltogether 36 cases of t(8;16) ANLL have been documented until today. We here review their clinical and cytogenetic features.

A translocation (14;19)(q32;q13.1) was found in a 31 year old man with a large cell lymphoma which had evolved from chronic lymphocytic leukaemia (CLL). Molecular analysis showed a monoclonal proliferation of B cells with rearrangement of the immunoglobulin (Ig) heavy and kappa light chain genes, and of the bcl-3 gene on chromosome 19q. Nine cases with t(14;19) from the literature were reviewed; B cell lymphoma had been diagnosed in eight and acute biphenotypic leukaemia in one of these cases. Four had transformed from CLL to a more aggressive disease, as in the present case. Two out of seven patients as well as the present one, with t(14;19) and CLL were young (less than 40). The t(14;19) is usually associated with other cytogenetic abnormalities; in our case a (15;16)(q15;p13) translocation was found and appears to be an additional nonrandom aberration in t(14;19) disorders.

The t(2;18)(p11;q21) has recently been described in two lymphoma cases as a variant of the t(14;18)(q32;q21) typical chromosome translocation in follicular lymphomas. Molecular investigations of t(2;18) confirmed juxtaposition of the bcl-2 gene to the immunoglobulin kappa (Igk) locus and described a new break point region on 18q21 found also in the recently reported, second follicular variant translocation (18;22)(q21;q11). Thus, cytogenetic and molecular studies established the same mechanism of (onco)gene activation by the heavy or light Ig gene in follicular lymphomas and Burkitt lymphomas. We describe a case of small non cleaved non Hodgkin's lymphoma in which translocation (2;18) coexisted with a typical (8;14) Burkitt translocation. Absent HLA-DR expression by the tumour cells was noted in this case. The possible implications of the cytogenetic and immunologic findings are discussed.

We report three cases of small B cell non Hodgkins lymphoma, two with plasmacytoid differentiation, presenting with a similar clinical picture and identical immunophenotype, who cytogenetically had breakpoints involving band 11q25. We suggest that this breakpoint may define a group of lymphomas closely related to the diffuse small cleaved cell lymphomas with t(11;14)(q13;q32).

Thirteen patients with B-non Hodgkin's lymphoma and abnormalities of the short arm of chromosome 1 were evaluated, to see if this cytogenetic anomaly was associated with a particular subgroup of lymphomas. Large cell lymphoma was found in seven patients (with an immunoblastic component in four cases). Six patients with diffuse small cleaved cell lymphoma of non follicle centre cell origin formed a second group. The chromosome 1 breakpoints in the second group were located between p34 and p36, suggesting that genes located here may be important in the initiation or progression of these lymphomas.