Search

The spontaneous formation of colony-forming units granulocyte/macrophage (CFU-GM) in semisolid cultures has been shown to be due to the endogenous release of cytokines and/or to the hypersensitivity of cells against growth factors. We have reported that increased autonomous CFU-GM growth is an in vitro characteristic of myelofibrosis (MF) which may reflect aberrant hematopoiesis in vivo. Because of its cytokine synthesis-inhibiting action, we speculated that interleukin-10 (IL-10) may inhibit pathological overproduction of myeloid cells in MF by suppression of autonomous myelopoiesis. In this study, IL-10 significantly inhibited autonomous CFU-GM formation in vitro from peripheral blood mononuclear cells (PB MNC) in 10 of 11 patients with MF tested. In all patients, there was a mean inhibition of 69% ranging from 35% to 100%. Suppression of autonomous CFU-GM formation by IL-10 was dose dependent and reversible by the addition of anti-IL-10 antibodies. Our results indicate that IL-10 is a potentially useful molecule to affect aberrant myelopoiesis in patients with MF.

Introduction Splenic marginal zone lymphoma (SMZL) is a rare low-malignant Non-Hodgkin lymphoma (NHL), in which immune mediated paraneoplastic phenomena such as autoimmune hemolytic anemia (AIHA), autoimmune thrombocytopenia (ITP) and C1 esterase inhibitor deficiency are relatively common. Materials and Methods We performed a multicenter retrospective study in 70 patients on the prevalence and clinical features of antiphospholipid antibodies (aPLA) in SMZL. Results and Conclusions Nine patients (13%) had the diagnosis of a lupus anticoagulant (LA). The occurrence of venous thromboembolic events was significantly higher in LA positive patients compared to LA negative patients (4/9 [44%] vs 5/61 [8%], p = 0.002), especially within 12 months after splenectomy (3/6 [50%] vs 2/28 [7%], p = 0.007). None of the patients with LA had a persistent complete remission of LA after splenectomy, but complete remission of LA was achieved in 2/2 patients after rituximab-bendamustine immuno-chemotherapy. In conclusion, our data show a relatively high prevalence of aPLA in SMZL and an increased risk of postsplenectomy thrombosis in these patients. The fact that rituximab-bendamustine was effective for eradicating LA may be considered as an argument for using immuno-chemotherapy as first line therapy in SMZL patients with LA.

A total of 20 patients with cold antibody hemolytic anemia were evaluated in a retrospective study of them, 15 had a monoclonal gammopathy of unknown significance (MGUS): 14 with MGUS of immunoglobulin M (IgM) subtype and 1 with immunoglobulin G subtype. One patient had smoldering Waldenström's macroglobulinemia, but four patients had no monoclonal protein and no evidence of lymphoma. However, in three of these patients, we were able to demonstrate a (mono-)clonal rearrangement of their immunoglobulin heavy and/or light chains. Of the 20 patients, 5 had IgHV34 nucleotide sequence indicating that the antibody was directed against the "I" antigen. Two patients exhibited a progressive increase of IgM over time, however without increasing hemolytic activity. Moreover, in two patients with long-term follow-up, we were able to correlate recurrent hemolytic activity with low environmental temperatures. Among four patients treated with rituximab, all four responded to treatment. However, treatment effect was only transient in all of them.

Bleeding and thrombosis are important complications in patients with malignant lymphomas. They may be due to direct actions of the lymphoma, such as venous compression or bone marrow infiltration, but they may also be caused by paraneoplastic phenomena, which are immune-mediated in most of the cases. The most important paraneoplastic immune-mediated disorders in lymphomas causing bleeding are autoimmune thrombocytopenia, acquired hemophilia A and acquired von Willebrand syndrome. In addition, there are a variety of other less common immune-mediated bleeding conditions, such as acquired thrombasthenia, acquired factor X-, V-, XI-, XII-, or prothrombin deficiency. The presence of antiphospholipid antibodies is a rare condition predisposing to venous and arterial thrombosis and there are other very uncommon conditions, which predispose exclusively to arterial thrombosis such as hyperlipidemic xanthomatosis. Interestingly, there is hardly any correlation between the histological type and the aggressiveness of lymphoma and the type and prevalence of the immune-mediated conditions. Successful treatment of the underlying lymphoma is often associated with definite and sustained resolution of the immune-mediated disorder.

We retrospectively studied the prevalence of C1 esterase inhibitor (C1 INH) deficiency in 131 patients with various lymphomas. We determined C1 INH activity, C1 INH antigen, and C4 concentration at diagnosis and after chemotherapy. In follicular lymphoma (FL), diffuse large B-cell lymphoma (DLBCL) and chronic lymphocytic leukemia (CLL) consecutive patients were studied. In these entities, the prevalence of C1 INH deficiency was 10.2% in DLBCL, 4.1% in CLL, and 0% in FL and Hodgkin lymphoma. In indolent lymphomas, we identified only single cases of C1 INH deficiency, predominantly in splenic marginal zone lymphomas (SMZL) (four cases). Only three patients were symptomatic while the majority (11 cases) was asymptomatic. In DLBCL patients who were successfully treated with chemotherapy, complete normalization of C1 INH activity and C4 was observed. In contrast, C1 INH deficiency remained in SMZL patients after splenectomy. We conclude that C1 INH deficiency in lymphomas is frequently asymptomatic and responsive to immunochemotherapy.

A 40-year-old woman is referred to you for a diagnostic evaluation of anemia. Until recently, she was asymptomatic and in good health. She has two healthy children aged 8 and 10 years. For a few weeks, she has been feeling weak for unknown reasons. In a laboratory examination of her blood, she had anemia with a hemoglobin of 9.0 g/dl with a normal leukocyte and platelet count.

Autoimmune hemolytic anemia is a heterogeneous disease with respect to the type of the antibody involved and the absence or presence of an underlying condition. Treatment decisions should be based on careful diagnostic evaluation. Primary warm antibody autoimmune hemolytic anemias respond well to steroids, but most patients remain steroid-dependent, and many require second-line treatment. Currently, splenectomy can be regarded as the most effective and best-evaluated second-line therapy, but there are still only limited data on long-term efficacy and adverse effects. The monoclonal anti-CD20 antibody rituximab is another second-line therapy with documented short-term efficacy, but there is limited information on long-term efficacy and side effects. The efficacy of immunosuppressants is poorly evaluated. Primary cold antibody autoimmune hemolytic anemias respond well to rituximab but are resistant to steroids and splenectomy. The most common causes of secondary autoimmune hemolytic anemias are malignancies, immune diseases, or drugs. They may be treated in a way similar to primary autoimmune hemolytic anemias, by immunosuppressants or by treatment of the underlying disease.

Autoimmune hemolytic anemia (AIHA) is a well known paraneoplastic phenomenon in lymphoproliferative disorders but there are also a number of case reports of such an association with solid tumors. We have analysed 52 cases of this association reported in the literature. We found that AIHA may occur prior to, concurrent with cancer or well after end of treatment, either as a sign of recurrence or in complete remission of the cancer. 70% of the patients had warm antibody and 30% cold antibody AIHA. Some patients had additional antibodies such as platelet antibodies (Evans syndrome), lupus anticoagulants or antibodies to C1 esterase inhibitor. AIHA occurred in almost all types of cancers, but it was relatively more common in renal cell cancer and Kaposi sarcoma compared to other cancers. In early stage cancers, in particular in renal cell cancers, curative resection of the cancers led to complete, often sustained remission of AIHA within a short time in a number of patients. Resection of the tumor had also beneficial effects in some metastatic cancers. Patients who had a response to resection of the tumor were often refractory to steroid treatment before surgery, while some responses to steroids were observed in patients with metastatic cancer. The study of cancer patients with autoimmune diseases may provide important insights into the biology of tumors.

Autoimmune cytopenias are typical paraneoplastic phenomena in malignant lymphomas. We assessed the occurrence, clinical, and laboratory features as well as the response to treatment of autoimmune hemolytic anemia, autoimmune thrombocytopenia, and neutropenia in published cases of Hodgkin lymphomas (HL). We identified 34 cases of an association between HL and autoimmune hemolytic anemia and 48 cases of an association of autoimmune thrombocytopenia (AITP) and HL. The autoimmune cytopenias (AIC) may occur prior to, concurrent with, at the time of recurrence of lymphoma or in complete remission after treatment. Almost all autoimmune hemolytic anemias were caused by warm antibodies. Patients with HL with AIC are more commonly males and are more likely to have mixed cellularity (MC) HL. HL is the only lymphoma which may be associated with autoimmune neutropenia. In contrast to AIC in diffuse large B-cell lymphoma (DLBCL), early stage is less common in patients with HL with AIC. AIC in HL respond better to antilymphoma treatment than to steroids, with the exception of post-treatment AITP in CR of HL which responds easily and durably to steroids.

The evolution of the mating system of a species is strongly influenced by the spatial and temporal distribution of females and/or resources. Here, we describe aspects of the territorial behavior of males of a solitary digger wasp, the European beewolf (Philanthus triangulum) and characterize the mating system. We show that beewolf males establish small territories that do not contain any resources essential to females. These territories are intensively scent-marked with a pheromone from a cephalic gland and are defended against intruders in combat flights. We provide evidence that scent-marking constitutes a chemical display and that the pheromone serves to attract receptive females and, thus, represents a sex pheromone. Using spatial statistics, we show that beewolf territories are clumped in space both with respect to other male territories and, more importantly, with respect to female nesting sites. Additionally, the proportion of days a territory is occupied by a male is correlated with the number of female nests in the vicinity. Taking into account that beewolf males do not defend or provide resources essential to females, but merely display chemically to attract females for mating in an aggregation of territories close to female nesting sites, we conclude that the European beewolf exhibits a hotspot lek polygyny with female nesting sites constituting “hotspots” for lek formation.

Circulating granulocyte/macrophage progenitor cells (CFU-GM) were assayed serially during remission in 17 patients with acute leukaemia (9 ALL, 8 AML). In patients with ALL receiving cyclophosphamide, 6-mercaptopurine and methotrexate, CFU-GM numbers were significantly lower than in normal individuals; cycles of 'reinduction' chemotherapy (vincristine, prednisolone) caused a 10-fold increase in CFU-GM per ml of blood. In 2 ALL patients a substantial increase in CFU-GM numbers preceded the morphologically detectable relapse. In patients with AML receiving repeated courses of cytosine-arabinoside and 6-mercaptopurine, circulating CFU-GM were likewise reduced. In 6 patients who relapsed, a further reduction of CFU-GM was seen. A complete absence of circulating CFU-GM was observed in 10 of the 23 investigations performed within 6 weeks prior to the morphologically detectable relapse, while such a 'zero'-growth occurred in only 1 of 54 experiments performed during stable remission. In summary, in patients with ALL in remission, circulating CFU-GM are increased following treatment with vincristine and prednisolone. In patients with AML, declining numbers of circulating CFU-GM may predict an imminent relapse.

16 patients with transfusion-dependent, life-threatening bone marrow failure (14 with severe aplastic anaemia, 1 with systemic lupus erythematosus and 1 with pure red cell aplasia) were treated with cyclosporin-A (Cy-A) after either lack of response to conventional immunosuppression with antithymocyte-globulin/high-dose methylpred-nisolone for 95 to 1190 days (median 186.5) (group I, 8 patients) or as a primary treatment due to ineligibility for conventional immunosuppression (group II, 8 pat.). Cyclosporin-A was given orally to maintain trough levels of 200 to 300 ng/ml (RIA). In group I, 6 out of 8 patients responded 30 to 480 d (median 53) and are currently alive 627 to 1482 d (median 731) after initiation of Cy-A, respectively. In 3 of the responders Cy-A has been withdrawn, without relapse. In group II, 5 of 8 patients responded 26 to 170 d (median 63) and are currently alive 142 to 697 (median 420) d following initiation of Cy-A, respectively. These data indicate a place for cyclosporin-A in the management of patients with life-threatening bone marrow failure in whom a) immunosuppressive therapy with antithymocyte-globulin and high-dose methylprednisolone had failed and b) who are not candidates for vigorous immunosuppression or bone marrow transplantation, for medical or other reasons.

12 patients with severe chronic idiopathic thrombocytopenic purpura (ITP) were treated with i.v. polyvalent intact immunoglobulin (0.14-0.4 g/kg body weight for 5 d) because of various bleeding episodes or prior to surgery. In 9 patients a significant rise in platelet counts was noted, starting on d 2 and reaching its maximum between d 4 and 11. Thereafter, platelet counts decreased slowly, approaching pre-treatment values after 20 d in most cases. Response to immunoglobulin was reproducible, when infusions were repeated. Response to high-dose immunoglobulin was independent of age of patients and duration of disease. Platelet-associated IgG decreased in all patients tested. A pepsin-treated immunoglobulin preparation was ineffective in 3 patients.

Diagnosis and management of immune thrombocytopenic purpura (ITP) remain largely dependent on clinical expertise and observations more than on evidence derived from clinical trials of high scientific quality. One major obstacle to the implementation of such studies and in producing reliable meta-analyses of existing data is a lack of consensus on standardized critical definitions, outcome criteria, and terminology. Moreover, the demand for comparative clinical trials has dramatically increased since the introduction of new classes of therapeutic agents, such as thrombopoietin receptor agonists, and innovative treatment modalities, such as anti-CD 20 antibodies. To overcome the present heterogeneity, an International Working Group of recognized expert clinicians convened a 2-day structured meeting (the Vicenza Consensus Conference) to define standard terminology and definitions for primary ITP and its different phases and criteria for the grading of severity, and clinically meaningful outcomes and response. These consensus criteria and definitions could be used by investigational clinical trials or cohort studies. Adoption of these recommendations would serve to improve communication among investigators, to enhance comparability among clinical trials, to facilitate meta-analyses and development of therapeutic guidelines, and to provide a standardized framework for regulatory agencies.

Autoimmune haemolytic anaemia (AIHA) is an immune disorder caused by antibodies directed against unmodified autologous red cells. The disorder may be a primary (idiopathic) or a secondary disease. The diagnosis is based on the presence of anaemia, signs of haemolysis with reticulocytosis, low haptoglobin, increased lactate dehydrogenase, elevated indirect bilirubin, and a positive direct antiglobulin test (Coombs test). Sometimes, not all of these typical features are present. Most AIHA are caused by warm antibodies, whereas cold antibodies are less commonly detected. While half of the warm antibody-based AIHA are idiopathic anaemias, almost all cold antibody AIHA are secondary anaemias. Underlying diseases are Non Hodgkin's lymphomas and systemic autoimmune disorders, and less frequently organ transplantation, infections, or solid tumors. Moreover, AIHA is an important complication of treatment with nucleoside analogs. Most patients with AIHA require therapy. In warm antibody AIHA, standard first line therapy are glucocorticosteroids with or without high dose immunoglobulins, whereas splenectomy is considered second-line therapy. Response rates of primary AIHA to corticosteroid therapy are high. After initial remission, the dose should be tapered down slowly and with caution, and in some cases, low-dose maintenance therapy is required. The efficacy of standard therapy is low in secondary AIHA that develops in lymphoma patients, posttransplant patients, or tumor patients. Among other immunosuppressive treatments, rituximab (anti-CD20) appears to be highly effective in patients with warm antibody AIHA refractory to standard therapy. Mycophenolate mofetil is quite effective in AIHA patients with an underlying autoimmune or lymphoproliferative disease. Patients with cold agglutinins are refractory to steroids and splenectomy. Half of these patients may respond to rituximab, although responses usually are short-lived. Sometimes, AIHA that is associated with malignant lymphomas or tumors, disappears after successful anti-lymphoma or anti-tumor therapy.

Early allogeneic hematopoietic stem cell transplantation (HSCT) has been proposed as primary treatment modality for patients with chronic myeloid leukemia (CML). This concept has been challenged by transplantation mortality and improved drug therapy. In a randomized study, primary HSCT and best available drug treatment (IFN based) were compared in newly diagnosed chronic phase CML patients. Assignment to treatment strategy was by genetic randomization according to availability of a matched related donor. Evaluation followed the intention-to-treat principle. Six hundred and twenty one patients with chronic phase CML were stratified for eligibility for HSCT. Three hundred and fifty four patients (62% male; median age, 40 years; range, 11-59 years) were eligible and randomized. One hundred and thirty five patients (38%) had a matched related donor, of whom 123 (91%) received a transplant within a median of 10 months (range, 2-106 months) from diagnosis. Two hundred and nineteen patients (62%) had no related donor and received best available drug treatment. With an observation time up to 11.2 years (median, 8.9 years), survival was superior for patients with drug treatment (P = .049), superiority being most pronounced in low-risk patients (P = .032). The general recommendation of HSCT as first-line treatment option in chronic phase CML can no longer be maintained. It should be replaced by a trial with modern drug treatment first.

We report on four cases (three women, one man, age at diagnosis 26-61 years) with severe autoimmune thrombocytopenia (AITP) who were refractory to initial steroid therapy (n = 4), to subsequent splenectomy (n = 2), azathioprine (n = 1), and cyclosporine (n = 1). Over years they received low-dose continuous or intermittent steroid therapy. After 6 to 31 years these patients achieved a "spontaneous" complete remission (CR) (n = 3) or partial remission (PR) (n = 1) unrelated to any specific second or third line treatment; CR/PR are sustained for 0.5+ to 9+ years. These data indicate that spontaneous remissions may occur in AITP even after a long duration of the disease.

Background and Objectives Rituximab, a monoclonal chimeric antibody to the CD20 antigen, is an effective therapy for the treatment of non-Hodgkin’s lymphomas. Moreover, rituximab has also shown to be effective in various autoimmune diseases including spontaneous antibodies to factor VIII. The aim of this study was to assess the efficacy of rituximab treatment of spontaneous inhibitors to factor VIII.Design and Methods We studied the efficacy of rituximab by analyzing the data of 42 previously published cases as well as one so far unpublished case. For comparison, we also analyzed 44 patients treated with cyclophosphamide/prednisone reported in the literature.Results Treatment with rituximab resulted in an overall rate of complete remission (CR) of 78.6%. Similar results were found when analyzing patients who had (75%) or had not (77%) received previous treatment with other immunosuppressive drugs. The median time to CR was 8.3 weeks. In follow-up 66% of the patients were still in CR after 2 years and the plateau in the Kaplan-Meier analysis suggests that a substantial number of patients had been cured. Among the 44 patients treated with cyclophosphamide/prednisone reported in the literature, the CR rate was 84.1%, which was slightly higher than that for rituximab. The median time to CR with cyclophosphamide/prednisone treatment was 6.3 weeks, which was similar to that in the rituximab-treated patients; the probability of continuous CR at 2 years was 94%.Interpretation and Conlusions All in all, both treatment schemes are effective therapies in patients with spontaneous antibodies to factor VIII. Our data analysis is only descriptive and no conclusions can be drawn as to the relative efficacy of the two regimens. However, these data may serve as a useful basis for planning randomized studies to definitively resolve these issues.

We analyzed 108 cases of non-CLL non-Hodgkin lymphoma (NHL) associated with autoimmune hemolytic anemia (AIHA) (+/- pure red cell aplasia (PRCA)) or Evans' syndrome. The analysis was based on cases reported in the literature, which were retrieved by means of Pubmed and Medline searches and of an original series of 121 patients with NHL as well as reference lists of papers in the field. The number of cases in various NHL subtypes was small (n = 6-25). Nevertheless, interesting and sometimes unexpected differences in sex prevalence, temporal relationship between onset of lymphoma and AIHA, stage of lymphoma, relative frequency of warm antibody-AIHA (WA-AIHA) and cold antibody (CA-AIHA), association with PRCA and response of AIHA to treatments were noted for various lymphoma entities. WA-AIHA was more frequent in B-cell lymphomas, while CA-AIHA and PRCA predominantly occurred in T-cell lymphomas. Anti-lymphoma treatment seemed to be more effective against AIHA than conventional therapy with steroids or immunoglobulin. Although generated by a literature survey, this compilation of data indicates a complex relation of lymphoma and AIHA and warrants more attention and specific studies.

Primary warm autoimmune hemolytic anemia (WAIHA) is a rare autoimmune disorder frequently responding to corticosteroid first-line treatment and effective second-line treatment options such as splenectomy or anti-CD20 antibody therapy. Disease management is frequently hampered by a lack of evidence. We have investigated the probability of sustained treatment-free remission after steroid induction to facilitate clinical decision making regarding timing and necessity of second-line treatments. Response data from 31 patients with primary WAIHA initially treated with steroids were retrospectively analyzed. All patients responded by achieving a hemoglobin of at least 10 mg/dl. After steroid tapering and final withdrawal, 9 of 30 patients remained in unsustained complete remission (CR). The probability of remaining in CR after steroid treatment only was 38.2 % (2 SD 20.6 %) at 15 months. The median remission duration was 100 + months with a range of 12 + to 163 + months. Of note, none of the remaining patients still on steroids achieved CR beyond 15 + months. These data indicate that a considerable proportion of patients do not need further treatment and that relapses will not occur after 15 months in CR.

The incidence of AITP is 20-30/million/year. The diagnosis is based on the finding of an isolated thrombocytopenia without other blood abnormalities and absence of a palpable spleen. Additional tests such as bone marrow examination, determination of platelet antibodies and of thrombopoetin are required only in special cases. The usual first line therapy in patients with bleeding tendency and a low platelet count is prednisolone at a dose of 1 mg/kg/day. Patients who have platelet counts of less than 20,000/microl 3-6 months after steroid therapy are candidates for splenectomy, in particular if more than 0.1 mg/kg/day prednisolone is required to keep the patient free of bleedings. Laparoscopic splenectomy has a low mortality (0.2%) and morbidity (10%). The risk of post-splenectomy overwhelming pneumococcal septicaemia can be minimized by preoperative vaccination. Older patients, who have low platelet counts after splenectomy, have a high bleeding risk. The most effective treatment options for these patients are cyclophosphamide, azathioprine and rituximab, but the choice of treatment should be carefully considered, since the risk of adverse effects may be greater than the risk of fatal bleeding.

Cobalamin deficiency is a common finding. In the elderly the prevalence is 10-20%, but only 5-10% of these are clinically symptomatic. Typical clinical symptoms include macrocytic anemia, neuropsychiatric symptoms and glossitis. In many cases this triad is lacking, however. The serum cobalamin assay is the best first line test, but the results must be carefully interpreted, since a normal level does not exclude deficiency. Markers of cobalamin activity, such as serum homocysteine or methylmalonic acid may be helpful in this situation. The main cause of cobalamin deficiency is atrophic gastritis. It is either caused by an autoimmune process which leads to achlorhydria and severe intrinsic factor deficiency ("classical pernicious anemia") or by atrophic gastritis from other causes, in particular helicobacter pylori infection. In the latter cases the lack of gastric acid does not allow separation of cobalamin from proteins, but intrinsic factor, although low, is sufficient for cobalamin protection (food cobalamin malabsorption). Helicobacter pylori eradication may cure some of these patients. While in food cobalamin malabsorption syndrome small doses of oral cobalamin are effective, parenteral therapy or high oral doses are required for treatment of pernicious anemia. While almost all patients respond hematologically, only half of the patients with neurological signs, and a small minority of psychiatric patients respond to treatment. Patients with pernicious anemia and atrophic gastritis have a greatly increased long-term risk for gastric carcinoids.

Background Limited data exist on the risk of pregnancy-associated venous thromboembolism (VTE) in women with a history of VTE. Objective To evaluate the risk of recurrent pregnancy-associated thrombosis in women with previous VTE in a large retrospective cohort study. Patients and methods One hundred and fifty-nine women with at least one pregnancy (293 pregnancies in total) after a VTE were included into the study. The patients underwent a standardized interview on their history of thrombosis and pregnancy-associated complications. Results Eight recurrent events occurred during 197 pregnancies without thrombosis prophylaxis. The probability of VTE during pregnancy without thrombosis prophylaxis was 6.2% (95% confidence interval 1.6-10.9%). The risk was constant over the whole period of pregnancy. Of the eight women with VTE during pregnancy four had heterozygous FV:R506Q, two in combination with hyperhomocysteinemia. No VTE occurred during 87 pregnancies with thrombosis prophylaxis. In the postpartum period 15 VTEs occurred, two of 83 (2.4%) after pregnancy termination, one of 53 (1.9%) after miscarriage, three of 10 (30%) after stillbirth and nine of 138 (6.5%) after live birth. Conclusions Without thrombosis prophylaxis the risk for recurrent symptomatic VTE is substantial during the whole period of pregnancy in women with previous VTE. The majority of events occurred after delivery, reflecting the very high risk during the postpartum period. Prospective and comparative trials to ascertain efficacy and safety of prophylactic heparin are urgently needed.

The association between malignant disorders and occurrence of venous thromboembolism is well established. Patients with cancer and venous thromboembolism have adverse prognosis. No systematic study on the incidence and prognostic impact of venous thromboembolism in acute leukemia has been performed as yet. We retrospectively evaluated the incidence of symptomatic venous thromboembolism before chemotherapy in 719 patients (371 males and 348 females, median age of 57.4 years), diagnosed with acute leukemia [534 with acute myelogenous leukemia, 185 with acute lymphoblastic leukemia]. Furthermore, the relationship of venous thromboembolism to clinical and laboratory parameters and its impact on prognosis was assessed. Fifteen patients (2.09%) had venous thromboembolism (objectively confirmed in 13 patients) in close temporal relationship to the onset of acute leukemia. The incidence of venous thromboembolism was the same in acute myelogenous and lymphoblastic leukemia. In five patients, pulmonary embolism was documented. Venous thromboembolism occurred in all subtypes of acute leukemia, but was most common in promyelocytic leukemia. All but one patient were treated with anticoagulants. No patient died from treatment-related bleedings or venous thromboembolism. Overall, survival, disease-free survival, and remission duration did not differ between the patient groups with and without venous thromboembolism. In contrast to solid tumors, venous thromboembolism before or at diagnosis of acute leukemia is not associated with poor prognosis.

Microvessel density reportedly is increased in various hematologic disorders including acute lymphatic and myeloid leukemias. In these patients the bone marrow microvessel density (BM-MVD) appears to be associated with an unfavorable prognosis. In the present study, we have retrospectively analyzed the BM-MVD (at diagnosis) in 31 patients with acute myeloid leukemia (AML) (median age: 38 years; range: 21 – 53 years; f : m-ratio: 1 : 1,4) who underwent conventional chemotherapy and consecutive allogeneic bone marrow transplantation (BMT). The median BM-MVD at diagnosis was 30/mm 2 (range: 17 – 48/mm 2 ) and thus was significantly higher compared to controls (n = 9; BM-MVD: median 7/mm 2 , range 2 – 11/mm 2 ; P 5 0.05). In patients who failed to achieve a complete remission (CR) in response to induction chemotherapy, the BM-MVD was significantly higher (median: 41.5/ mm 2 ) at diagnosis than in patients who entered CR (median: 28.5/mm 2 , P 5 0.05). In addition, patients with high BM-MVD ( 4 30 mm 2 ) had a significantly shorter overall survival compared to patients with a lower BM-MVD ( 5 30 mm 2 , P 5 0.05). Moreover, patients with a high BM-MVD ( 4 30 mm 2 ) were found to have a significantly higher risk of relapse (P 5 0.05). In 4 patients in whom a continuous complete remission was documented after BMT, the BM-MVD levels were analyzed at diagnosis as well as between day + 80 and day + 100 after BMT. In all 4 patients, the BM-MVD was found to decrease in response to BMT until day 100 (P 5 0.05). Together, our data suggest that the BM-MVD could be a prognostic parameter concerning survival in patients with AML undergoing allogeneic BMT.

Purpose: High-dose intermittent cytarabine is an effective postremission treatment for patients with acute myeloid leukemia (AML). This regimen is a safe approach in patients < 60 years but produced severe neurotoxicity in the elderly. Experimental Design: We have established a dose-reduced age-adapted consolidation using intermediate dose (IDAC; 2 × 1 g/m2 i.v., days 1, 3, and 5) for AML patients ≥ 60 years. Forty-seven de novo AML patients in complete remission (CR; median age, 70 years) were scheduled to receive four consolidation cycles of IDAC. Results: In 25 of 47 patients (53%), all four cycles were administered: 9 (19%) received three cycles; 7 (15%) received two cycles; and 6 patients (12%) one cycle. Treatment was well tolerated without neurotoxicity. The median number of days with severe neutropenia (absolute neutrophil count < 500/μl) was 9. Neutropenic fever occurred in 22 of 47 patients (49%) during the first cycle, in 24 of 41 (60%) during the second, in 15 of 34 (44%) during the third, and in 18 of 25 (72%) during the fourth cycle. Only 1 patient died during consolidation (cardiac failure). The median overall survival, disease-free survival, and continuous CR were 10.6, 15.5, and 15.9 months, respectively. The probability of overall survival, disease-free survival, and continuous CR at 5 years were 18, 22, and 30%, respectively. Conclusions: IDAC is a safe and effective postremission therapy for elderly patients with AML.

Myelodysplasia associated with a complex karyotype is usually associated with advanced stage myelodysplastic syndrome (MDS) and an enhanced risk to develop secondary leukemia. We report on a 36-year-old female patient who was first presented in 1997 because of ‘Pseudo Pelger–Huet’ neutrophils. The remaining blood and differential counts were normal. Bone marrow examination revealed dysplasia in the erythroid and granulocytic series, no increase in blasts, and a karyotype with complex aberrations involving chromosomes 7, 13, 20 and 22. Almost all metaphases examined appeared to be affected. During the next few months, the patient was closely monitored and considered as candidate for bone marrow transplantation. However, blood counts remained stable without occurrence of significant cytopenias or an increase in blasts. Re-examinations of the bone marrow in 1998 and 1999 disclosed identical results compared to that obtained in 1997. After a total follow up of 6 years, the patient is still in good health with normal blood counts and persisting ‘Pseudo Pelger–Huet’ neutrophils. This exceptional case supports the notion that complex chromosomes are not invariably associated with rapid disease evolution in MDS.

We have originally shown that spontaneous granulocyte/macrophage colony (CFU-GM) formation in semisolid medium is a characteristic in vitro feature of chronic myelomonocytic leukemia (CMML). However, the clinical significance of spontaneous CFU-GM growth in CMML is unknown so far. CFU-GM growth characteristics were studied in semisolid cultures in the absence of exogenous cytokines using peripheral blood mononuclear cells in 30 patients with CMML at first presentation. The median number of CFU-GM/10(5) MNC of all patients was 48.5 (range 0-622) with 18 patients having colony numbers below 100 (low CFU-GM growth) and 12 patients above 100 (high CFU-GM growth). Kaplan-Meier analysis revealed that patients with high CFU-GM growth had a significantly shorter survival than patients with low CFU-GM growth (median 6.5 vs. 44.5 months, p0.00002). The probability of survival after 2 years was 60.5% for patients with low colony growth but 0% in those with high colony formation. Patients with CFU-GM100 had a significantly higher WBC count, a higher LDH, and a higher number of blast cells in blood and bone marrow than patients with low colony growth. Moreover, patients with high colony growth had more often splenomegaly and lower platelet counts. In seven patients, in whom semisolid in vitro cultures were performed after transformation into RAEBT/AML, spontaneous colony growth was significantly increased as compared to CFU-GM growth in patients before transformation (median number/10(5) MNC 533, range 212-4553, p0.005). This study demonstrates that high (100) spontaneous CFU-GM formation in CMML at presentation correlates with increased disease activity and represents a novel and important prognostic factor predicting for short survival of CMML patients.

Anti-beta2-glycoprotein I (beta2GPI) antibodies are frequently found in patients with lupus anticoagulant (LA). To investigate the prevalence of antibeta2GPI antibodies and their clinical impact in patients with a history of venous thromboembolism (VTE) without LA/anticardiolipin antibodies (ACA), we studied 503 patients [128 (36.2%) men, median age 41 years (interquartile range, IQR 28-54 years)] with previous thrombosis. A group of 113 individuals without VTE [43 (38.1%) men, age 46.7 years (IQR 38-52 years)] served as a control group. Among 418 patients without LA/ACA, anti-beta2GPI-IgG levels were elevated in seven (1.7%), -IgM in 15 (3.6%) and -IgA in 14 (3.3%) cases; in 58 patients with ACA, anti-beta2GPI-IgG levels were elevated in two (3.4%), six (10.3%) and three (5.2%), and in 27 with LA, they were elevated in 18 (66.7%), 19 (70.4%) and 10 (37%) respectively. Thus, the prevalence of elevated anti-beta2GPI antibodies was not increased in patients without LA/ACA but was strongly associated with LA. Patients without ACA/LA who had a recurrent event did not have higher prevalence of elevated anti-beta2GPI-IgG, -IgM or -IgA antibodies than those without a recurrent event. Thus, elevated antibeta2GPI antibodies are not likely to be a predictor of recurrent events in patients without LA. We conclude that determination of anti-beta2GPI antibodies does not improve the clinical management of patients with a history of VTE without LA/ACA.

BACKGROUND: ABO mismatch has not been thought to affect the outcome of patients undergoing myeloablative conditioning and allogeneic HPC transplantation. Data on transplant-related complications after ABO-mismatched transplantation after nonmyeloablative conditioning are limited. STUDY DESIGN AND METHODS: Therefore, 40 patients were analyzed after nonmyeloablative conditioning with regard to ABO compatibility. Eleven received a minor and bidirectional and 8 a major ABO-mismatched graft. RESULTS: Four patients had evidence of hemolysis during engraftment, being lethal in one, and three developed pure RBC aplasia. Six patients in the ABO-mismatched group developed thrombotic microangiopathy, and three of them died. ABO-identical and ABO-mismatched patients had a similar incidence of GVHD. Viral infections occurred in both groups in equal shares. Patients with an ABO-mismatch had to be rehospitalized until Day 100 for a median of 19 days versus 0 days in the identical group (p < 0.05). Overall survival was 60 and 57 percent in the ABO-identical and ABO-mismatch groups, respectively. The probability of transplant-related mortality was 0 versus 28 percent in the identical group compared to patients with an ABO mismatch (p < 0.05). The probability of relapse or progression was 76 versus 25 percent in the ABO-identical group compared to the ABO-mismatched group, respectively. CONCLUSION: Significantly more patients with ABO mismatch showed transplant-associated complications and died as a result of transplant-related causes.

We report on a 35-year-old woman who underwent allogeneic stem cell transplantation (SCT) in second complete remission (CR) of acute myeloid leukemia (AML) after reduced-intensity conditioning with fludarabine and 2 Gy of total body irradiation. For graft-versus-host disease (GVHD) prophylaxis, cyclosporin A (CsA) and mycophenolate mofetil (MMF) were given. On day 27 after SCT complete hematological remission and donor chimerism was documented. However, in CD34(+) bone marrow cells 28% of recipient hematopoiesis persisted. On day +59 leukemic relapse occurred. After discontinuation of CsA and onset of GVHD, complete donor chimerism and hematological CR were achieved which has been maintained for 14 months.

The growth characteristics and the prognostic value of cytokine-stimulated myeloid colony formation from peripheral blood mononuclear cells (PBMC) of patients with myelodysplastic syndromes (MDS) are largely unknown. In this study we have determined the number of myeloid colony-forming units (mCFUs) in semisolid medium from 112 MDS patients and correlated them with French-American-British (FAB) type, the international prognostic scoring system (IPSS), karyotype, peripheral blood (PB) and bone marrow (BM) blast cells, cytopenias, lactate dehydrogenase (LDH), and survival data. Concerning the FAB classification, lower median mCFUs were found in patients with refractory anemia (RA) and refractory anemia with ringed sideroblasts (RARS) compared to refractory anemia with excess of blast cells (RAEB) and refractory anemia with excess of blasts cells in transformation (RAEB-T). In vitro growth in MDS clearly correlated with the cytogenetic risk groups defined by the IPSS (30.5/10(5) PBMCs with favorable karyotypes, 191 in the intermediate prognostic group, 677 with unfavorable cytogenetics, p=0.015 favorable vs unfavorable). BM blast cells >5% (60.5 vs 255 colonies, p=0.032) as well as LDH levels above the normal limit (64.5 vs 425 colonies, p=0.045) were also associated with higher colony formation. Patients were stratified according to the number of circulating mCFUs into a low growth, intermediate growth and high growth group. Median survival was 343 days in the high growth, 1119 days in the low growth, and 2341 days in the intermediate growth group ( p=0.0002). Multivariate analyses revealed colony growth ( p=0.0056), PB blast cells ( p=0.0069), cytogenetic risk group ( p=0.024), and platelet count ( p=0.018) to predict survival in our patients. After inclusion of the IPSS risk categories, mCFU levels remained a highly predictive parameter for survival ( p=0.0056) and acute myeloblastic leukemia (AML) transformation ( p=0.0003).

A total of130 consecutive patients with severe autoimmune thrombocytopenia (AITP) who were diagnosed and treated in our institution between 1991 and 2001 were followed up. The patients were almost exclusively treated with prednisolone, immunoglobulin and/or splenectomy. The aim ofthe treatment was to keep the platelet count at least above 10 000 mL. None of the patients died from bleeding, two patients died from infection and seven from other unrelated causes. These data show that AITP is a relatively benign disease that does not require aggressive treatment. Bleeding can be prevented ifthe platelet count can be kept above 10 000 mL. The Hematology Journal (2003) 4, 366–369. doi:10.1038/sj.thj.6200299

Remarkable results of the treatment of refractory multiple myeloma with thalidomide have been reported. In most preceding studies, the given thalidomide dose was escalated to a maximum tolerated dose of up to 800 mg/d. The frequency of adverse effects correlates with dose intensity. Since a significant gain of therapeutic effects could not be observed as thalidomide dosage was escalated, the optimal dose of thalidomide remains to be determined. We report the results of a study with low dose thalidomide (median administered dose 100 mg/d, range 50-400 mg/d). Twenty-four relapsed (n = 19) or resistant (n = 5) multiple myeloma patients were included in the study. Twelve patients (50%) received thalidomide as monotherapy, 8 patients (33%) received a combination of thalidomide and dexamethasone (every 4 weeks 40 mg/day for 4 days) and 4 patients (17%) who were resistant to vincristine, doxorubicin, dexamethasone (VAD) received VAD combined with thalidomide. Overall, a response was observed in 12 patients (50%). Of the 12 patients treated with low dose thalidomide alone 5 (42%) responded, of the 8 patients who received a combination of thalidomide and dexamethasone 5 (63%) responded and of the 4 patients who had thalidomide in addition to VAD 2 patients (50%) responded. In 3 patients, thalidomide treatment had to be discontinued because of side effects and 1 patient died before response could be assessed. We conclude that low dose thalidomide is an effective and safe rescue therapy in relapsing or refractory multiple myeloma. Response to thalidomide might be dependent on prognostic parameters and tumor burden. To answer these questions larger prospective studies are necessary.

We assessed long-term outcome in 155 patients who had undergone an allogeneic/syngeneic stem cell transplant (SCT) and were in complete remission for more than 2 years after transplant. Probability of late transplant-related mortality was 6%, and affected only patients with chronic graft-versus-host disease (cGVHD). Thirteen percent of patients experienced relapse. Overall survival projected at 10 and 15 years was 83% and 76%, respectively. Secondary malignancies occurred in two patients, 7.5 and 11 years after SCT. Three female and four male patients parented children 19 to 84 months after SCT. Quality of life (QoL) was assessed in a cross-sectional study by the means of a 30-item questionnaire (QLQ-C30) of the EORTC. The questionnaire was sent to 127 patients remaining alive and answered by 106 patients. Seventy-three percent reported a good to very good QoL within 5 years after SCT and 78% after this time point. However, patients with cGVHD had significant impairment of physical, role and social functioning and only 60% of them were fit for work. These results from long-term survivors show that high cure rates with good to very good QoL can be achieved by allogeneic or syngeneic SCT.

Polycythemia Vera (PV) and Essential Thrombocythemia (ET) are chronic myeloproliferative disorders complicated by a high incidence of thrombotic complications. Extensive coagulation studies failed to demonstrate a consistent pattern of abnormalities associated with thrombosis. Recently, a poor anticoagulant response to activated protein C (APC), due to a mutation of factor V (FV Leiden), has been identified as the most frequent hereditary disorder associated with venous thrombophilia. We investigated in 304 patients with PV and ET whether the presence of FV Leiden could be a risk factor for thrombosis. FV Leiden was found in 14/304 patients (4.6%) and was associated with venous thromboembolism (VTE) occurred before and at diagnosis (5/27,16%, with a significant difference of prevalence in comparison of that observed in asymptomatic patients, 9/263, 3%, p = 0.003). Carriership of FV Leiden was associated with VTE relapse, with a prevalence of 3.6% in asymptomatic patients, 6.9% in patients with a single episode of VTE and 18.1% in patients with recurrent VTE. The prevalence of FV Leiden in patients with and without arterial thrombosis was similar (5/79, 6% and 9/211, 4%, respectively, p = 0.337). This study indicates that the prevalence of the FV Leiden mutation in patients with PV and ET is comparable with that observed in the general population. FV Leiden mutation is a risk factor for VTE before and at time of diagnosis and for VTE recurrences. Screening for FV Leiden may be considered to identify PV and ET patients at higher risk of recurrences. Am. J. Hematol. 71:1–6, 2002. © 2002 Wiley-Liss, Inc.

Summary. We present a 60-year-old patient with primary refractory non-Hodgkin's lymphoma and a 58-year-old patient with multiple myeloma with relapse after first autologous stem cell transplantation (ASCT), who underwent ASCT followed by allogeneic stem cell transplantation (alloSCT) with reduced intensity conditioning consisting of fludarabine and a single dose of total body irradiation. For graft-versus-host disease prophylaxis cyclosporine and mycophenolate mofetyl were given. Complete donor chimaerism was observed on d 28 after SCT. Both patients achieved sustained complete haematological and molecular remission of the immunoglobulin kappa light chain (Igκ) rearrangement and are alive and well 17 and 16 months after SCT respectively.

Summary. Between 1982 and 2000, 172 patients with acute myelogenous leukaemia (AML) received haematopoietic stem cell transplants (SCT) from related (n = 132) or unrelated (n = 40) donors at four Austrian transplant centres and their results were reported to the Austrian Stem Cell Transplantation Registry. Conditioning for SCT consisted of cyclophosphamide and total body irradiation in 156 (91%) patients. Graft-versus-host disease (GVHD) prophylaxis was with standard cyclosporine and methotrexate in 95 (55%) patients. Median post-transplant follow-up was 5·6 years (range, 0·2--16·7). Multivariate analysis of transplant-related mortality (TRM) identified four variables associated with a lower risk: disease status of first complete remission (CR) at SCT, patient age of 45 years and younger, transplant performed during or after 1995, and lack of acute GVHD. Variables associated with significantly improved leukaemia-free survival were: bone marrow as the stem cell source, disease status of first CR at SCT, and occurrence of chronic GVHD. In multivariate analysis, transplantation performed during or after 1995, first CR at SCT, occurrence of limited chronic GVHD and lack of acute GVHD grades III to IV were associated with increased overall survival. Based on these analyses, options for the improvement of results obtained with allogeneic SCT in patients with AML could be defined.

We studied the incidence of leukemia cutis (LC) in 381 consecutive patients with acute myeloid leukemia (AML) in a single institution and compared the demographic, hematological, and cytogenetic findings in AML patients with and without LC. We also examined the response to intensive chemotherapy, overall survival, and duration of remission in this patient population with regard to the presence of LC. The prevalence of LC was 3.7% in clinically diagnosed patients and 2.9% in biopsy-proven cases, respectively. Patients with and without LC did not differ with regard to age, sex, white blood cell counts, hemoglobin, fibrinogen, and platelet counts at diagnosis, but lactate dehydrogenase (LDH) was significantly higher in patients with LC. Various karyotype abnormalities were found, but in patients with LC numerical abnormalities of chromosome 8 were significantly more common ( P0.0001). Patients with LC did not differ from patients without LC with regard to remission rate, but there was a trend towards shorter remission duration in patients with LC. We conclude that patients with LC have some features different from patients without this symptom. The increased frequency of numerical aberrations of chromosome 8 in patients with LC was the most interesting observation of our study. The pathophysiological significance of this finding remains to be determined.

Internal tandem duplication of the FLT3 gene (FLT3/ITD) has been linked to poor outcome in acute myeloid leukemia (AML). However, the prognostic value of FLT3/ITD in various cytogenetic risk groups is still a matter of debate. The aim of this study was to evaluate the prognostic significance in patients with de novo AML and a normal karyotype or a t(15;17), t(8;21) or inv(16) (good risk group).Diagnostic samples of 100 patients were investigated by single-step PCR of exons 11 and 12 of the FLT3 gene in a single center retrospective analysis. Subgroups included 53 patients with normal karyotype, 21 patients with t(15;17), 9 patients with t(8;21) and 17 patients with inv(16).FLT3/ITD was found in 26 out of 100 patients: 30% of patients with a normal karyotype and 38% of t(15;17) patients tested positive. The complete remission (CR) rates for the ITD(+) or ITD(-) groups were 50 vs 76% in normal karyotypes, and 100 vs 53% in t(15;17) patients, while the relapse rates were 75 vs 25% in normal karyotypes and 50 vs 42% in t(15;17) patients. Overall survival (OS) and disease free survival (DFS) at 5 years were significantly different in patients with normal cytogenetics: ITD(+) vs ITD(-): OS 6 vs 28% (P0.003); DFS 13 vs 41% (P0.02) Interestingly, FLT3/ITD had no significant effect on the outcome of t(15;17) patients: ITD(+) vs ITD(-): OS 85 vs 53% (P=0.056), DFS 45 vs 60% (P=0.6) at 50 months.These data suggest a high prognostic value of FLT3/ITD in patients with normal cytogenetics. However, we find no evidence that FLT3/ITD is a predictive marker for patients with t(15;17).

Although systemic mastocytosis (SM) is a well-defined hematologic neoplasm, it is sometimes difficult to discriminate between SM and a reactive mast cell (MC) hyperplasia. We describe a patient with aplastic anemia who was treated with recombinant stem cell factor (SCF). In response to SCF, the patient showed transient hematologic improvement and developed a marked increase in MC as well as a transient increase in serum tryptase. Histologic and immunohistochemical examination revealed a huge increase in MC in the bone marrow with focal infiltrates similar to SM. However, most of the SM-criteria were not met: First, MC showed normal cytomorphological characteristics without significant atypias (no cytoplasmic extensions, no oval nuclei, no hypogranulated cytoplasm). Furthermore, bone marrow MC were CD2- and CD25-negative and did not exhibit the C-KIT 2468 A--T mutation (Asp-816-Val). After discontinuation of SCF the MC hyperplasia resolved confirming its reactive nature. Based on our case and similar cases mimicking mastocytosis, it seems of importance to apply recently established SM criteria in order to discriminate between reactive MC hyperplasia and true mastocytosis with certainty.

Background: Mast cells (MCs) are multifunctional effector cells of the immune system. These cells originate from pluripotent hemopoietic progenitors. In contrast to basophils and other leukocytes, MCs exhibit a remarkably long life span (years) in vivo. Although a role for stem cell factor (SCF) and SCF receptor (KIT) in long-term survival of MCs has been proposed, the underlying biochemical mechanisms remain unknown. Materials and Methods:We have examined expression of ‘survival-related’ molecules of the bcl-2 family including bcl-2 and bcl-xL, in primary human MCs and the human MC line HMC-1. Primary MCs were isolated from dispersed lung tissue by cell sorting using an antibody against KIT. mRNA expression was analyzed by RT-PCR and Northern blotting. Results: As assessed by RT-PCR, purified unstimulated lung MCs (>98% pure) exhibited KIT- and bcl-xL mRNA, but did not express bcl-2 mRNA. However, exposure of lung MCS to SCF (100 ng/ml) for 8 h resulted in expression of bcl-2 mRNA. Corresponding results were obtained by immunocytochemistry. In fact, exposure of MC to SCF resulted in expression of the bcl-2 protein whereas unstimulated MCs displayed only the bcl-xL protein without expressing the bcl-2 protein. The human MC leukemia cell line HMC-1, which contains a mutated and intrinsically activated SCF receptor, showed constitutive expression of both bcl-2 and bcl-xL at the mRNA and protein level. Conclusion: Our data show that human MCs can express members of the bcl-2 family. It is hypothesized that bcl-xL plays a role in KIT-independent growth of MCs, whereas bcl-2 may be involved in KIT-dependent functions of MCs.

SummaryVenous thromboembolism represents a significant cause of morbidity worldwide. The factors that underly thrombophilia are manifold. The concept of Virchow defines the well known triad of stasis, humoral factors, and pathologies of the vascular wall. In the current article, an additional factor, the “accumulation of repair cells” is discussed. This novel concept highlights the mast cell that accumulates around thrombosed vessels and provides a number of important repair molecules including heparin, profibrinolytic tPA, and fibrinogenolytic β-tryptase. Thus, mast cell recruitment and activation may result in local thrombolysis and prevention of coagulation. In line with this concept, mast cell-deficient mice are more susceptible to lethal thrombogenic stimuli compared to normal mice. The factors (cytokines) that trigger mast cell accumulation and release of repair molecules have also been identified – the most important one appears to be stem cell factor (SCF). All in all, our novel concept suggests that the patho-physiology of thrombosis may involve a “physiologic” cell that provides the same repair molecules that are used for treatment of thrombotic disorders by the physician. Whether an altered availability of components of this cellular repair system can predispose for thrombophilia remains to be determined.

In the two consecutive German studies III and IIIA on chronic myeloid leukemia, between 1995 and 2004, 781 patients were randomized to receive either allogeneic hematopoietic stem cell transplantation with a related donor or continued drug treatment. Despite comparable transplantation protocols and most centers participating in both studies, the post-transplant survival probabilities for patients transplanted in first chronic phase were significantly higher in study IIIA (144 patients) than in study III (113 patients). Prior to the decision on a combined analysis of both studies, reasons for this discrepancy had to be investigated.The Cox proportional hazard cure model was used to identify prognostic factors for post-transplant survival.Donor-recipient matching for human leukocyte antigen, patient age, time between diagnosis and transplantation, and calendar time showed a significant influence on survival and/or the incidence of cure. Added as a further factor, affiliation to study IIIA had no significant impact any longer.Discrepancies in influential prognostic factors explained the different post-transplant survival probabilities between the studies. The significance of calendar time suggests a lack of consistency of transplantation practice over time. Accordingly, the prerequisite for a common assessment of overall survival in the two randomized transplantation arms was not met. Moreover, our analyses provide an independent validation of established prognostic factors and their cutoffs. The statistical approach in investigating and modeling potential prognostic factors for survival sets an example for the examination of studies with unexpected outcome differences in concurrent treatment arms.

Recent data suggest that mast cells (MCs) in patients with systemic mastocytosis or mast cell leukemia express a CD2-reactive antigen. To explore the biochemical nature and function of this antigen, primary MCs as well as the MC line HMC-1 derived from a patient with mast cell leukemia were examined. Northern blot experiments revealed expression of CD2 messenger RNA in HMC-1, whereas primary nonneoplastic MCs did not express transcripts for CD2. In cell surface staining experiments, bone marrow (BM) MCs in systemic mastocytosis (n = 12) as well as HMC-1 cells (30%-80%) were found to express the T11-1 and T11-2 (but not T11-3) epitopes of CD2. By contrast, BM MCs in myelodysplastic syndromes and nonhematologic disorders (bronchiogenic carcinoma, foreskin phimosis, uterine myeomata ) were consistently CD2−. All MC species analyzed including HMC-1 were found to express LFA-3 (CD58), the natural ligand of CD2. To study the functional role of CD2 on neoplastic MCs, CD2+ and CD2− HMC-1 cells were separated by cell sorting. CD2+ HMC-1 cells were found to form spontaneous aggregates and rosettes with sheep erythrocytes in excess over CD2−cells, and a T11-1 antibody inhibited both the aggregation and rosette formation. Moreover, exposure of CD2+ HMC-1 cells to T11-1 or T11-2 antibody was followed by expression of T11-3. In addition, stimulation of neoplastic MCs through T11-3 and a second CD2 epitope resulted in histamine release. These data show that neoplastic MCs express functionally active CD2. It is hypothesized that expression of CD2 is associated with pathologic accumulation and function of MCs in systemic mastocytosis.

Background The myelodysplastic syndromes (MDS) are a group of clonal haematological disorders characterized by cytopenia(s), reduced differentiation-capacity of myeloid cells, and impaired leukocyte function. However, little is known so far about basophil granulocytes in MDS. Design We have compared the numbers, phenotype and function of basophils in MDS patients with those in healthy subjects. A total numer of 23 patients with MDS (refractory anaemia, n = 8; refractory anaemia with ringsideroblasts, n = 7; refractory anaemia with excess of blasts/refractory anaemia with excess of blasts in transformation, n = 8) and 20 healthy donors were included. Results The numbers of blood basophils in MDS patients (34.6 +/- 62.9 microL-1) was lower compared to healthy controls (58.6 +/- 64.9 microL-1). Correspondingly, whole blood histamine levels were lower in MDS patients (MDS 34.1 +/- 29.1 ng mL-1 vs. normal donors 72.0 +/- 36.9 ng mL-1). Like "normal" basophils, basophils in MDS expressed interleukin-3 receptor alpha (CD123), E-NPP3 (CD203c), CR1 (CD35), CR3 (CD11b), CR4 (CD11c), membrane co-factor protein (CD46), decay-accelerating factor (CD55) and membrane attack complex inhibitory factor (CD59), as well as receptors for C3a, C5a (CD88), and IgE. Recombinant human (rh) C5a and anti-IgE induced significant release of histamine from basophils in both groups of donors without significant differences between MDS and healthy controls. Conclusions The absolute numbers of basophils in MDS patients are lower than in normal donors. However, basophils in MDS do not differ from their "normal counterparts" in terms of complement receptor expression, IgE-receptor expression, or functional responses to respective ligands.