Bone Marrow Necrosis in Newly Diagnosed Acute Leukemia: Two Case Reports and Review of the Literature.

Bone marrow necrosis (BMN) in acute leukemia is a rare histopathological entity at the time of initial diagnosis. However, it represents an important diagnostic and prognostic challenge. Two cases of BMN are reported: a 44-year-old patient with B cell precursor (BCP) acute lymphoblastic leukemia (ALL) and a 27-year-old man with FAB-M5 acute myeloid leukemia (AML) who both presented with bone marrow failure and extensive necrosis. From these clinical cases, we conducted a brief review of the literature.

Splenic diffuse red pulp lymphoma has a distinct pattern of somatic mutations amongst B-cell malignancies.

Splenic Diffuse Red Pulp Lymphoma (SDRPL) has been recently introduced as a provisional entity but differential diagnosis with other splenic lymphomas is needed to be clarified since the therapeutic approaches are distinct. Recently described recurrent mutations or CD180 expression appear useful for differential diagnosis. We completed our previous description in a larger cohort including 53 patients selected on the presence of characteristic villous cells in peripheral blood (PB) and a specific immunophenotype. Immunoglobulin heavy variable (IGHV), BRAF, MYD88, and NOTCH2 mutations were determined and CD180 and BRAF expressions were assessed. Most cases (79%) were IGHV mutated with an overrepresentation of IGHV3-23 (19%) and IGHV4-34 (21%). MYD88 L265P and NOTCH2 mutations were observed in one case each, whereas no BRAF V600E mutation or expression was found. All cases demonstrated a high CD180 expression. Those results strengthen the concept that SDRPL does emerge as a new lymphoma entity distinct from the other splenic lymphomas with circulating lymphocytes.

Rapamycin safeguards lymphocytes from DNA damage accumulation in vivo.

Several studies reported the benefits of switching from anticalcineurins to mTOR inhibitors to avoid cancer occurrence after organ transplantation. The purpose of our study was to determine in vivo biological markers to explain these benefits. Cellular changes related to cellular senescence and DNA damage were analyzed in peripheral blood lymphocytes. Thirty-five kidney transplanted patients receiving anticalcineurins were investigated: 17 patients were proposed to switch to rapamycin and 18 patients with similar age and transplantation duration, continued anticalcineurins. Rapamycin effects were studied one year after the switch. Thirteen healthy volunteers and 18 hemodialyzed patients were evaluated as control. Compared with the healthy group, hemodialyzed and transplanted patients exhibited a significant decrease in telomere length, an increase in p16(INK4A) mRNA expression and in lymphocytes with 53BP1 foci. A destabilization of the shelterin complexes was suggested by a significant TIN2 mRNA decrease in transplanted patients compared with controls and a significant increase in TRF1, TRF2 and POT1 expression in switch-proposed patients compared with the non-switched subgroup. Rapamycin treatment resulted in a significant decrease in DNA damage and a slight TIN2 increase. In vitro experiments strengthened in vivo results showing that rapamycin but not FK506 induced a significant DNA damage decrease and TIN2 expression increase compared with controls. The roles of rapamycin in the decrease in DNA damage in vivo and the rescue of shelterin gene expression are demonstrated for the first time. These data provide new insights into understanding of how rapamycin may overcome genomic injuries.

The ibrutinib B-cell proliferation inhibition is potentiated in vitro by dexamethasone: Application to chronic lymphocytic leukemia.

New B-cell receptor-targeted therapies such as ibrutinib, a Bruton tyrosine kinase inhibitor, are now proposed for lymphoid pathologies. The putative benefits of its combination with glucocorticoids were evaluated here. We compared the effects of dexamethasone (DXM), ibrutinib and their in vitro combination on proliferation and metabolic stress markers in stimulated normal B-lymphocytes and in malignant lymphocytes from chronic lymphocytic leukemia (CLL) patients. In both cellular models, cell cycle progression was globally inhibited by DXM and/or ibrutinib. This inhibition was significantly amplified by DXM addition to ibrutinib and was related to a significant decrease in the expression of the cell cycle regulatory proteins CDK4 and cyclin E. Apoptosis increased especially with DXM/ibrutinib combination and was associated with a significant decrease in Mcl-1 expression. Treatment effects on metabolic stress were evaluated by DNA damage recognition after 53BP1 foci labeling. The percentage of cells with more than five 53BP1 foci decreased significantly with ibrutinib in normal and CLL lymphocytes. This decrease was strongly reinforced, in CLL, by DXM addition. Our data indicated that, in vitro, DXM potentiated antiproliferative effects of ibrutinib and decreased DNA damage in lymphoid B-cells. Thus their combination may be proposed for CLL treatment.

CD1d-restricted peripheral T cell lymphoma in mice and humans.

Peripheral T cell lymphomas (PTCLs) are a heterogeneous entity of neoplasms with poor prognosis, lack of effective therapies, and a largely unknown pathophysiology. Identifying the mechanism of lymphomagenesis and cell-of-origin from which PTCLs arise is crucial for the development of efficient treatment strategies. In addition to the well-described thymic lymphomas, we found that p53-deficient mice also developed mature PTCLs that did not originate from conventional T cells but from CD1d-restricted NKT cells. PTCLs showed phenotypic features of activated NKT cells, such as PD-1 up-regulation and loss of NK1.1 expression. Injections of heat-killed Streptococcus pneumonia, known to express glycolipid antigens activating NKT cells, increased the incidence of these PTCLs, whereas Escherichia coli injection did not. Gene expression profile analyses indicated a significant down-regulation of genes in the TCR signaling pathway in PTCL, a common feature of chronically activated T cells. Targeting TCR signaling pathway in lymphoma cells, either with cyclosporine A or anti-CD1d blocking antibody, prolonged mice survival. Importantly, we identified human CD1d-restricted lymphoma cells within Vδ1 TCR-expressing PTCL. These results define a new subtype of PTCL and pave the way for the development of blocking anti-CD1d antibody for therapeutic purposes in humans.

The p16(INK4A)/pRb pathway and telomerase activity define a subgroup of Ph+ adult Acute Lymphoblastic Leukemia associated with inferior outcome.

Adult Acute Lymphoblastic Leukemia (ALL) therapies have been improved by pediatric-like approaches. However, treatment failures and relapses are common and new markers are needed to identify patients with poor prognosis in prospective trials. The p16(INK4A)/CDK4-6/pRb pathway and telomerase activity, which are implicated in cell activation and aging, were analyzed to identify new prognostic markers. Proteins of the p16(INK4A)/CDK4-6/pRb pathway and telomerase activity were analyzed in 123 adult B-cell precursor (BCP) ALL cases included in the GRAALL/GRAAPH trials. We found a significantly increased expression of p16(INK4A) in BCP-ALLs with MLL rearrangement. Telomerase activity was significantly lower in Philadelphia chromosome-negative/IKAROS-deleted (BCR-ABL1(-)/IKAROS(del)) cases compared to Philadelphia chromosome-positive (BCR-ABL1+) BCP-ALLs. In BCR-ABL1+ ALLs, high CDK4 expression, phosphorylated pRb (p-pRb) and telomerase activity were significantly associated with a shorter disease-free survival (DFS) and event-free survival (EFS). Enhanced p16(INK4A) expression was only related to a significantly shorter DFS. In vitro analyses of normal stimulated lymphocytes after short- and long-term cultures demonstrated that the observed protein variations of poor prognosis in BCR-ABL1+ ALLs may be related to cell activation but not to cell aging. For these patients, our findings argue for the development of therapeutic strategies including the addition of new lymphocyte activation inhibitors to current treatments.

Aplastic anemia as a feature of systemic lupus erythematosus: a case report and literature review.

Peripheral cytopenias are common in systemic lupus erythematosus, but bone marrow involvement is rarely reported. Aplastic anemia is the result of immune-mediated destruction of hematopoietic stem cells causing pancytopenia and characterized by an empty bone marrow. This rare but serious disease has been described as an unusual manifestation of systemic lupus erythematosus. We reviewed the 25 cases published in the English language literature and discuss the clinical presentation, outcome, treatment, and pathophysiology of aplastic anemia as a complication of systemic lupus erythematosus. We report here the first case of aplastic anemia associated with systemic lupus erythematosus treated with an allogeneic hematopoietic stem cell transplant. Over one half of patients received concomitantly the diagnoses of systemic lupus erythematosus and aplastic anemia. No clinical or histological features can distinguish primary aplastic anemia from aplastic anemia occurring in systemic lupus erythematosus patients. The overall mortality is about 15% and corticosteroid-based therapy alone or in combination with other immunomodulatory drugs can restore bone marrow function. Systemic lupus erythematosus may be complicated by bone marrow involvement. The diagnosis of peripheral cytopenias should be confirmed by bone marrow aspiration. All these patients should receive cortisone as a first treatment. Plasma exchanges seem to have some efficacy. Other different immunomodulatory therapies were used with variable results.

Bone marrow fibrosis as a feature of systemic lupus erythematosus: a case report and literature review.

INTRODUCTION: Peripheral cytopenias are common in systemic lupus erythematosus (SLE), but bone marrow involvement is rarely reported. Myelofibrosis is a rare disorder characterized by reticulin fibrosis of the bone marrow, which usually occurs in response to clonal proliferation of hematopoietic stem cells in myeloproliferative disorders. However, bone marrow fibrosis has also been described in association with auto-immune diseases, especially SLE. METHOD: We will report here a new case of bone marrow fibrosis associated with SLE. We also reviewed the 27 cases published in the English language literature, and will discuss the clinical presentation, outcome, treatment, and pathophysiology of bone marrow fibrosis occurring in association with SLE. RESULTS: Over one half of patients were diagnosed concomitantly with bone marrow fibrosis and SLE. Epidemiological, clinical and biological features of lupus were unremarkable. Except for the presence of reticulin fibrosis, the findings from the bone marrow biopsies proved highly variable. Overall mortality was about 14% but corticosteroid-based therapy lead to clinical improvement and reverted bone marrow fibrosis in most cases. Data on the usefulness of other immunomodulatory therapies are inconclusive. CONCLUSIONS: SLE may be complicated by bone marrow involvement, of a likely autoimmune origin. Bone marrow fibrosis occurring with SLE is probably similar to "primary autoimmune myelofibrosis" and may respond to steroid and immunomodulatory therapies. Further studies with standardised proofreading of bone marrow aspirations and biopsies are needed to delineate the clinical and biological features of this rare complication of SLE.

Long-term follow-up analysis of 100 patients with splenic marginal zone lymphoma treated with splenectomy as first-line treatment.

Splenectomy is considered as one of the first-line treatments for symptomatic patients with splenic marginal zone lymphoma (SMZL). Between 1997 and 2012, 100 hepatitis C virus-negative patients with SMZL were treated by splenectomy as first-line treatment. At 6 months, all patients but three recovered from all cytopenias. The median lymphocyte count at 6 months and 1 year was 11.51 × 10(9)/L and 6.9 × 10(9)/L, respectively. Median progression-free survival (PFS) was 8.25 years. The 5-year and 10-year overall survival (OS) rates were 84% and 67%, respectively. Histological transformation occurred in 11% of patients, and was the only parameter significantly associated with a shorter time to progression (p = 0.0001). Significant prognostic factors for OS were age (p = 0.0356) and histological transformation (p = 0.0312). In this large retrospective cohort, we confirmed that splenectomy as first-line treatment in patients with SMZL corrected cytopenias and lymphocytosis within the first year and was associated with a good PFS.

Peripheral blood involvement in patients with follicular lymphoma: a rare disease manifestation associated with poor prognosis.

Follicular Lymphoma (FL) is the second most common non-Hodgkin lymphoma (NHL) subtype and its course is heterogeneous. At diagnosis, some patients with FL manifest a detectable leukaemic phase (FL-LP), but this feature has been seldom described and is poorly characterized. Among 499 patients diagnosed with FL in Lyon-Sud hospital, 37 (7·4%) had characteristic FL-LP (by cytological blood smears and flow cytometric analysis). In addition, 91/1135 FL patients from the PRIMA study presented FL-LP at study entry. In order to evaluate the outcome of this Lyon-Sud cohort, FL-LP patients were matched with 111 newly diagnosed FL without LP according to the Follicular Lymphoma International Prognostic Index (FLIPI) score, age and treatment. Presence of FL-LP was associated with shorter progression-free survival (PFS) and overall survival (OS) (P = 0·004 and P = 0·031, respectively). Presence of FL-LP and high FLIPI score remained independent prognostic factors in a Cox model for time to progression (TTP). A number of circulating lymphoma cells (CLC) >4 × 10(9) /l was the most significant predictor for a shorter TTP in this Cox model. The prognostic impact of FL-LP on TTP was validated in the PRIMA cohort (P = 0·0004). In conclusion, FL-LP is a rare event associated with shorter PFS and patients with CLC >4 × 10(9) /l have a poorer outcome. These patients should be monitored carefully to consider alternative therapeutic options.

Primitive CML cell expansion relies on abnormal levels of BMPs provided by the niche and on BMPRIb overexpression.

Leukemic stem cells in chronic phase chronic myelogenous leukemia (CP-CML) are responsible for disease persistence and eventual drug resistance, most likely because they survive, expand, and are sustained through interactions with their microenvironment. Bone morphogenetic proteins 2 (BMP2) and 4 (BMP4) regulate the fate and proliferation of normal hematopoietic stem cells, as well as interactions with their niche. We show here that the intrinsic expression of members of the BMP response pathway are deregulated in CML cells with differences exhibited in mature (CD34(-)) and immature (CD34(+)) compartments. These changes are accompanied by altered functional responses of primitive leukemic cells to BMP2 and BMP4 and strong increases in soluble BMP2 and BMP4 in the CML bone marrow. Using primary cells and a cell line mimicking CP-CML, we found that myeloid progenitor expansion is driven by the exposure of immature cells overexpressing BMP receptor Ib to BMP2 and BMP4. In summary, we demonstrate that deregulation of intracellular BMP signaling in primary CP-CML samples corrupts and amplifies their response to exogenous BMP2 and BMP4, which are abnormally abundant within the tumor microenvironment. These results provide new insights with regard to leukemic stem cell biology and suggest possibilities for the development of novel therapeutic tools specifically targeting the CML niche.

Immunoarchitectural patterns in splenic marginal zone lymphoma: correlations with chromosomal aberrations, IGHV mutations, and survival. A study of 76 cases.

AIMS: To describe 76 cases of splenic marginal zone lymphoma (SMZL), including correlations with clinical and other characteristics. METHODS AND RESULTS: Patients were predominantly female, with a median age of 62 years. The main clinical presentation was splenomegaly, except for eight cases presenting with evolution of autoimmune disorders or spontaneous splenic rupture. White pulp infiltration was nodular, with a monophasic (42%) or biphasic (53%) pattern, and associated diffuse or nodular infiltration of the red pulp, except for four cases which had atrophic white pulp. Plasmacytic differentiation and the MYD88 L265P mutation were observed in 18% and 5% of the cases, respectively. Histological progression was considered in cases with a significant association of large cells with Ki67 > 30% and macronodular architecture (P = 0.001). Other significant correlations were found between del7q (44%) and del6q (17%) (P = 0.018), IGHV1-2*04 segment usage (35%) (P = 0.001) and unmutated IGHV (39%) (P = 0.019), and between CD5 expression (27%) and higher lymphocytosis (P = 0.002). Patients requiring intensive chemotherapy after splenectomy because of clinical and/or histological progression had significantly shorter overall survival (P = 0.012). CONCLUSIONS: We report the histological spectrum of SMZL, and discuss the differential diagnosis and requirement for molecular and cytogenetic analysis in atypical cases.

Granulomatous lesions in bone marrow: clinicopathologic findings and significance in a study of 48 cases.

PURPOSE: Granulomas in bone marrow are an infrequent finding related to various disorders. The aim of this study was to review our clinical experience with granulomatous bone marrow disease and to describe the contributions of recent diagnostic tools, such as (18)F-Fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) and molecular biology. METHODS: Clinical, laboratory and morphological data on patients with a granuloma based on bone marrow biopsy analysed in the University Hospital Lyon from May 2004 to July 2010 were reviewed. RESULTS: We identified 57 cases among 9641 bone marrow biopsies, representing an incidence of 0.59% in the series and an annual incidence of 9.5 cases per year. Nine biopsies performed for staging a known pathology were excluded from further analysis. Among the 48 remaining patients, associated disease was demonstrated in 79%, with infections being the most common (33%), following by sarcoidosis (21%), malignancy (19%) and therapy-induced granulomas (6%). One previously unpublished entity is described: infection with Bartonella henselae diagnosed using molecular biology from node and skin biopsies in two renal transplant patients. (18)F-FDG-PET, performed in 13 cases, showed hypermetabolic foci consistent with sarcoidosis in two cases. Positive PCR result for an infectious pathogen was obtained in three bone marrow samples (Mycobacterium tuberculosis, n=1; Mycobacterium genavense, n=2). CONCLUSION: In comparison to previous research, our study reports high proportions of cases caused by sarcoidosis and unknown causes. (18)F-FDG-PET could show signs consistent with sarcoidosis and molecular biology is useful for the detection of fastidious bacteria in immunocompromised patients.

In non-follicular lymphoproliferative disorders, IGH/BCL2-fusion is not restricted to chronic lymphocytic leukaemia.

The translocation t(14;18) and its t(2;18) and t(18,22) variants, which involve the BCL2 genetic hallmark for follicular lymphoma (FL), have been reported in several cases of chronic B-cell lymphoproliferative disease (CLPD) and frequently in chronic lymphocytic leukaemia (CLL). We describe here the clinical, morphological, immunological, cytogenetic and molecular findings from 37 cases of t(14;18)-positive CLPD, identified from our series of non-FL B-cell neoplasms (n=993) that were routinely analysed in peripheral blood by conventional cytogenetics analyses. The FL diagnosis was excluded by morphology and immunology (the samples were CD10 negative in all cases). The BCL2 translocations were observed in 22 CLL cases, including 7 monoclonal B-cell lymphocytosis (MBL) cases re-classified according to the new International Workshop on CLL criteria, six small lymphocytic lymphoma (SLL) cases, 1 splenic marginal zone lymphoma (SMZL) case and eight cases of unclassifiable CLPD with overlapping CLL/MZL features. In the CLL cases, the IGH/BCL2 fusion was remarkably associated with trisomy 12 (13/22) and mutated IGHV status (20/21) and did not affect the outcome. Moreover, most of these CLLs harboured a low mutation load of BCL6 gene and unmutated FAS (CD95) loci, which points to a post-germinal-centre cellular origin.

CD10 and ICOS expression by multiparametric flow cytometry in angioimmunoblastic T-cell lymphoma.

Angioimmunoblastic T-cell lymphoma is immunologically defined by the expression of CD10 and the follicular helper T cell (T(FH)) markers such as CXCL13, programmed death-1 (PD-1) and inducible T-cell costimulator (ICOS). This T(FH) profile has been mainly reported by immunohistochemistry. Here, using multiparametric flow cytometry, the relevance of ICOS and PD-1 to angioimmunoblastic T-cell lymphoma diagnosis was evaluated in lymph node (n=15) as well as in peripheral blood (n=13) among a series of 28 angioimmunoblastic T-cell lymphoma cases, in addition to the CD10 expression (available in 26 lymph node and 15 peripheral blood specimens). In this series, CD10 expression was present in 23/26 (88%) lymph node and in 12/15 (80%) peripheral blood cases and ICOS in 13/15 (87%) lymph node and in 6/13 (47%) peripheral blood cases, whereas neither significant CD10 nor ICOS T cells were identified in the control group (lymph nodes with reactive hyperplasia=10, peripheral blood of healthy donors=15). PD-1 expression was less informative as observed in both angioimmunoblastic T-cell lymphoma and control cases. The multiparametric approach allowed us to confirm the frequent blood dissemination in angioimmunoblastic T-cell lymphoma and to show that circulating neoplastic T cells correspond more often to a CD10-positive subset than to an ICOS-positive subset. Consequently, if ICOS constitutes an additional feature for the diagnosis of angioimmunoblastic T-cell lymphoma, it appears less sensitive than CD10 expression for the detection of circulating neoplastic T cells.

S-phase lengthening induced by p16(INK4a) overexpression in malignant cells with wild-type pRb and p53.

The p16(INK4a) protein is considered to regulate the cell cycle progression mainly by inhibiting cyclin-dependent kinases (CDKs) 4 and 6 activity and leading to an arrest in G(0)/G(1). Here, we report that ectopic expression of p16(INK4a) in three p16-/pRb(Wt)/p53(Wt) human cancer cell lines MCF7, U2OS and U87 induces S-phase lengthening along with G(1) accumulation. S-phase lengthening is suggested by the discrepancy between the unchanged or even increased percentage of cells in S phase found by flow cytometry DNA content analysis and the drop of BrdU labelling, and demonstrated by IdU/BrdU double labelling. p16(INK4a) induces a profound decrease in the CDK4/6-mediated pRb phosphorylation on Ser-807/811, a downregulation of CDK2 and CDK1 protein expression independently of G(1) accumulation, and a decrease in Thr/Pro phosphorylation in part carried out by CDKs. In MCF7 cells, overexpression of the p16 G101W mutant, which is unable to inhibit CDK4/6 kinase activity and shows a modified subcellular localization, does not provoke the S-phase lengthening and the inhibition of Ser807/811-pRB and of Thr/Pro phosphorylation as wild-type p16(INK4a) does. Our results demonstrate that p16(INK4a) induces a S-phase lengthening independently of cellular origin. The CDK4/6 kinase activity inhibition together with the reduced expression of CDK2 and CDK1 acting downstream of G(1) phase may prevent cells from any possible kinasic compensatory mechanisms, and thus lead to a cell cycle progression inhibition.

Lymphoma recurrence 5 years or later following diffuse large B-cell lymphoma: clinical characteristics and outcome.

PURPOSE Patients with diffuse large B-cell lymphoma (DLBCL) usually relapse early following diagnosis but some relapses happen at 5 years or later. Few data exist regarding clinical characteristics and outcome of these patients. PATIENTS AND METHODS We performed a retrospective analysis of all patients from two centers in Lyon, France, between 1985 and 2003 who had a biopsy-proven relapse 5 years or later following diagnosis of DLBCL. All available biopsies were reviewed and immunohistochemistry was completed. Results Among 1,492 patients with DLBCL, 54 were eligible. At diagnosis, 63% of patients had stage I-II, 82% had low/low-intermediate International Prognostic Index (IPI) score, 65% had extranodal involvement, 24% had an indolent component associated with DLBCL, 57% had germinal center phenotype, and 43% had non-germinal center phenotype. Median time from diagnosis to relapse was 7.4 years (range, 5 to 20.5 years). At time of relapse, 83% had DLBCL histology, and 17% had indolent histology. Having an indolent component at diagnosis was associated with indolent histology at relapse (P = .028). Five-year event free-survival (EFS) was 17% for patients with DLBCL relapse and 61% for patients with indolent relapse (P = .027). Five-year overall survival was 27% for patients with DLBCL and 75% for patients with indolent relapse (P = .029). For DLBCL relapse, 3-year EFS was 56% versus 18% with autologous stem-cell transplantation or not, respectively (P = .0661). CONCLUSION Patients with DLBCL who had a late relapse usually had localized stage, favorable IPI score, and extranodal involvement at diagnosis. The outcome of patients with DLBCL at time of relapse remains poor, and aggressive treatment such as autologous stem-cell transplantation should be pursued whenever possible. Biopsy at relapse is essential because some patients relapse with indolent histology.