Tamar Tadmor

Merkel cell carcinoma, chronic lymphocytic leukemia and other lymphoproliferative disorders: an old bond with possible new viral ties

Merkel cell carcinoma (MCC) is a rare and aggressive skin tumor. The link between tumorigenesis and immunosuppression is well known and the increased prevalence of MCC in human immunodeficiency virus carriers and organ transplant recipients and in patients with hemato-oncological neoplasias is now well recognized over the past decade. In this respect, chronic lymphocytic leukemia (CLL) seems to be the most frequent neoplasia associated with the development of MCC. Very recently, a newly described virus, the Merkel cell polyomavirus, was found in ∼80% of MCC tumor samples and is in fact the first member of the polyomavirus family to be associated with human tumors. The virus appears to play a role in the pathogenesis of MCC and may constitute the missing link between immunosuppression and the development of MCC. This review summarizes the current knowledge relating to MCC and its pathogenesis, stressing the link with hematologic neoplasias in general and to CLL in particular. We describe the permissive immunologic environment, which enables the virus-containing tumor cells to survive and proliferate in disorders like CLL. More studies are still needed to confirm this appealing theory in a more convincing manner.

Absolute monocytosis at diagnosis correlates with survival in diffuse large B‐cell lymphoma—possible link with monocytic myeloid‐derived suppressor cells

Some patients with lymphoma have monocytosis at diagnosis, but its significance is unclear. The recently recognized subpopulation, monocytic myeloid‐derived suppressor cells (M‐MDSCs), has immunoregulatory function, suppresses host anti‐tumour immunity and plays a role in cancer tolerance. Data from 91 untreated patients with diffuse large B‐cell lymphoma (DLBCL) were evaluated for monocytosis >1000/mm3 at diagnosis and its significance compared with a number of well‐established prognostic factors for DLBCL including age, stage, gender, B symptoms, extranodal sites, LDH and CRP levels, bone marrow involvement and International Prognostic Index (IPI) score. In 23 of these patients with DLBCL and 15 healthy controls, the proportion of M‐MDSCs in the peripheral blood was determined by flow cytometry. Monocytosis was found in 17.6% of the patient cohort examined. In the multivariate analysis, bone marrow involvement, IPI score and monocytosis were the only independent prognostic factors seen to be associated with decreased progression free and overall survival. Patients with DLBCL had on average increased M‐MDSCs counts at diagnosis compared with controls, which returned to normal after achieving remission. In conclusion, monocytosis was identified as an independent prognostic factor in DLBCL and correlated with worse overall survival. The significant increases in the M‐MDSCs pool observed in some of the cases examined may possibly help to explain why monocytosis is associated with poor outcome in these patients. Copyright

Primary diffuse large B-cell lymphoma of the breast: looking at pathogenesis, clinical issues and therapeutic options

Primary breast lymphoma is a rare form of non-Hodgkin lymphoma with some distinct clinical features. The most common histopathological type is diffuse large B-cell lymphoma (DLBCL), but other less frequent subtypes are also encountered. In this review, we describe the characteristics of primary breast DLBCL, with emphasis on pathogenesis, staging, risk stratification and prognosis. In addition, key issues regarding therapy and various available therapeutic modalities are addressed, as well as the role of rituximab in therapy and whether central nervous system prophylaxis is still routinely required. There are very few prospective clinical studies addressing therapy, and available data rely mostly on retrospective case series involving small numbers of patients. Our conclusions and proposed recommendations are therefore not offered as formal guidelines. This review attempts to represent an unbiased analysis of the published data and is intended as a useful aid for clinicians treating this uncommon type of extra nodal lymphoma.

Predicting infections in high‐risk patients with myelodysplastic syndrome/acute myeloid leukemia treated with azacitidine: Aretrospective multicenter study

Hypomethylating agents have become the standard therapy for patients with high‐risk myelodysplastic syndrome (MDS). In Israel, azacitidine (AZA) is routinely used. Yet, infectious complications are common during AZA therapy. The current study was aimed to evaluate the incidence and predisposing risk factors for infections in AZA‐treated patients. This retrospective study included patients treated with AZA in 18 Israeli medical institutions between 2008 and 2011. Data on 184 patients [157 high‐risk MDS and 27 acute myeloid leukemia (AML)], with a median age of 71.6 (range 29–92) were recorded. Overall, 153 infectious events were reported during 928 treatment cycles (16.5%) administered to 100 patients. One hundred fourteen, 114/153 (75%) events required hospitalization and 30 (19.6%) were fatal. In a univariate analysis, unfavorable cytogenetics, low neutrophil, hemoglobin (Hb) and platelet (PLT) counts were found to be associated with infections (24.4% vs. 12.9%, P < 0.0001; 27% vs. 13.5%, P < 0.0001; 20.4% vs. 11%, P < 0.0001 and 29.2% vs. 14.2%, P < 0.0001, respectively). In multivariate analysis, only low Hb level, low PLT count, and unfavorable cytogenetics remained significant. Prior to therapy, poor cytogenetics, PLT count below 20 × 109/L and neutrophil count below 0.5 × 109/L were predictive of the risk of infection during the first two cycles of therapy. In conclusion, patients with unfavorable cytogenetics, presenting with low neutrophil and PLT counts, are susceptible to infections. Evaluation of infection risk should be repeated prior to each cycle. Patients with poor cytogenetics in whom AZA is prescribed despite low PLT count are particularly at high risk for infections and infection prophylaxis may be considered. Am. J. Hematol. 88:130–134, 2013.

Richter syndrome in chronic lymphocytic leukemia: updates on biology, clinical features and therapy.

Abstract Richter syndrome (RS) or Richter transformation is the development of secondary aggressive lymphoma in the setting of underlying chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Most frequently CLL transforms into diffuse large B-cell lymphoma (DLBCL) (90%) and rarely (10%) into Hodgkin lymphoma, termed Hodgkin variant of Richter syndrome (HvRS). RS is generally characterized by an aggressive clinical course and poor prognosis. In recent years, major advances have been made in understanding genetic events which relate to the progression of CLL or transformation into RS. Better understanding of the molecular pathways has revealed that RS is not a single homogeneous entity. The majority of cases are clonally related to the original CLL clone, while a minority develop from an unrelated clone. This review summarizes new data relating to the molecular biology and the genetic/epigenetic changes occurring during Richter transformation, and also considers the clinical features and therapy for both DLBCL-RS and Hodgkin variant-RS.

The expression of lysyl-oxidase gene family members in myeloproliferative neoplasms.

Myeloproliferative neoplasms (MPNs) are malignant disorders originating from clonal expansion of a single neoplastic stem cell and characteristically show an increase in bone marrow reticulin fibers. Lysyl oxidases (LOXs) are copper‐dependent amine oxidases that play a critical role in the biogenesis of connective tissue by crosslinking extracellular matrix proteins, collagen and elastin. Expression of LOX gene family members is increased in disorders associated with increased fibrosis. To evaluate involvement of LOX gene family in various MPNs. In‐situ hybridization was used to detect Lysyl‐Oxidase family members in bone marrow biopsies from patients with different MPNs. We compared normal bone marrows and those from patients with polycythemia vera, essential thrombocythemia, chronic myeloid leukemia, and primary myelofibrosis (PMF). Serum levels of lysyl‐oxidase from patients with PMF and healthy controls were also examined. LOX gene family was not detected in normal bone marrows. All members of the LOX gene family were over expressed in PMF. In other MPNs a differential pattern of expression was observed. Differences in gene expression were statistically significant (Pu2009<u20090.010). The medianserum LOX levels in normal controls was 28.4u2009±u20092.5 ngml and 44.6u2009±u20099.44 ngml in PMF (Pu2009=u20090.02). The varying pattern of expression of LOX genes may reflect differences in the pathophysiology of bone marrow fibrosis in these MPNs. These observations could be used as the basis for future targeted therapy directed against bone marrow fibrosis. Am. J. Hematol. 88:355–358, 2013.

Monocytosis Has Adverse Prognostic Significance and Impacts Survival in Patients with T-Cell Lymphomas.

In this retrospective study we evaluated the prognostic impact of peripheral blood monocytosis in patients with T-cell non Hodgkin lymphomas with aggressive-typically nodal presentation. In this dataset monocytes >0.8 × 10(9)/L had a strong and statistically significant negative impact on overall survival (OS). In univariate analysis several parameters, including age >60 years, advanced stage, bone marrow involvement, ECOG PS >1, high LDH level, monocytes >0.8 × 10(9)/L, hemoglobin<120 g/L, albumin<35 g/L) had a negative influence on outcome, but in multivariate analysis, monocytosis alone had a stronger association with poor OS.

Consensus guidelines for the diagnosis and management of patients with classic hairy cell leukemia

Hairy cell leukemia is an uncommon hematologic malignancy characterized by pancytopenia and marked susceptibility to infection. Tremendous progress in the management of patients with this disease has resulted in high response rates and improved survival, yet relapse and an appropriate approach to re-treatment present continuing areas for research. The disease and its effective treatment are associated with immunosuppression. Because more patients are being treated with alternative programs, comparison of results will require general agreement on definitions of response, relapse, and methods of determining minimal residual disease. The development of internationally accepted, reproducible criteria is of paramount importance in evaluating and comparing clinical trials to provide optimal care. Despite the success achieved in managing these patients, continued participation in available clinical trials in the first-line and particularly in the relapse setting is highly recommended. The Hairy Cell Leukemia Foundation convened an international conference to provide common definitions and structure to guide current management. There is substantial opportunity for continued research in this disease. In addition to the importance of optimizing the prevention and management of the serious risk of infection, organized evaluations of minimal residual disease and treatment at relapse offer ample opportunities for clinical research. Finally, a scholarly evaluation of quality of life in the increasing number of survivors of this now manageable chronic illness merits further study. The development of consensus guidelines for this disease offers a framework for continued enhancement of the outcome for patients.

Insect-bite-like reaction in patients with chronic lymphocytic leukemia: a study from the Israeli Chronic Lymphocytic Leukemia Study Group.

An insect‐bite‐like reaction is known to occur in patients with chronic lymphocytic leukemia (CLL). Most of the literature, however, consists of isolated case reports or small case series. The aim of this retrospective study was to review the national experience with insect‐bite‐like reaction in a large group of patients with CLL. The study cohort of patients with these skin reactions consisted of 48 patients (25 males, 23 females) of mean age 64.8 yr (range 33–89) at skin eruption. Data on clinical, histologic, immunophenotypic, and cytogenetic characteristics, treatment, and outcome were collected from the medical files. Mean time between diagnosis of CLL and appearance of the skin lesions was 3.1 yr (range −4 to 14 yr). The eruption was not related to disease activity or the course of the hematological disease. The eruption preceded the diagnosis of CLL in 10 patients (by 0–4 yr); and followed the diagnosis in 36; in 11 patients, it occurred during therapy for CLL and in nine after therapy. Mean duration of the skin findings was 21.5 months (range 0.3–132). The eruption usually presented in summer, although it occurred also at other times of the year, and predominantly affected the upper and lower limbs, although it also appeared on unexposed areas. Treatment included local ointments, antihistaminics, oral steroids, antibiotics, phototherapy, and dapsone with varying responses. Insect‐bite‐like reactions is a relatively common and disturbing skin reaction in CLL patients, it may be related to the immune dysregulation accompanying CLL and further exacerbated by external factors, including actual insect bites, chemoimmunotherapy, and pyogenic infection.

Higher Infection Rate After 7- Compared With 5-Day Cycle of Azacitidine in Patients With Higher-Risk Myelodysplastic Syndrome

INTRODUCTIONnAzacitidine (AZA) dose reduction is a common practice in cytopenic patients. However, a correlation between AZA dose and infection complications has never been studied.nnnPATIENTS AND METHODSnHigher-risk patients with myelodysplastic syndrome or acute myeloid leukemia treated with AZA in 18 Israeli hospitals between the years 2008 and 2011 were included in a former national survey. To reveal the effect of AZA dosage on infection risk we limited our analysis to the infection rate after the first AZA dose alone. We excluded subsequent cycles of AZA from the analysis, because infectious events during these cycles might be related to other cofactors such as disease response to AZA therapy.nnnRESULTSnAfter the first AZA cycle, infectious events were more frequent after doses of 75 mg/m(2) for 7 days than 75 mg/m(2) for 5 days (36/106 [34%] and 10/67 [14.9%], respectively; P = .008), regardless of the patients age. Of the 46 recorded infectious events, the causative pathogen was identified as bacterial in 25 (54.3%) and as viral or fungal in 2 (4.3%) and 2 (4.3%) cases, respectively. No pathogen was identified in 17 (37%) cases. Infections were significantly more prevalent among patients who presented with platelet counts < 20,000 (43.6% vs. 23.6%; P = .012) and poor risk cytogenetics (40.7% vs. 19.8%; P = .008).nnnCONCLUSIONnReduction of AZA dose might decrease infection rate and therefore should be considered in patients with high infection risk.