ALBERT

Description: Multidrug-resistant bacterial pathogens (MRP) such as extended-spectrum beta-lactamase producing enterobacteriaceae (ESBL), vancomycin-resistant enterococci (VRE) and methicillin-resistant staphylococcus aureus (MRSA) are an emerging challenge in allogeneic hematopoietic cell transplantation (HCT). However, to our knowledge there are no data in the existing literature on the prevalence of MRP and of the impact of these multidrug-resistant pathogens on the outcome after allogeneic HCT. Thus, it was the purpose of this study to systematically analyze the issue of MRP in patients who underwent allogeneic HCT. PATIENTS AND METHODS: From 06/2010 to 12/2013 a total number of 72 (F: n=23; M: n=49) consecutive patients who received the first allogeneic HCT at our institution were retrospectively analyzed. The underlying diseases were AML (n=44), ALL (n=5), CML (n=4), MPN (n=2), lymphoma (n=5), MDS (n=9), and multiple myeloma (n=3). The conditioning regimen was myeloablative in 23 patients and reduced intensity in 49 patients. Patients were transplanted with peripheral blood stem cells (n=69) or bone marrow (n=3) from matched siblings (n=19), matched unrelated (n=45), mismatched (n=5) or haploidentical donors (n=3). As baseline investigation before commencing with the conditioning all patients underwent a comprehensive screening for MRP, i.e. ESBL, VRE and MRSA. For that reason swabs from nose, throat, axilla, urethra and anus as well as stool and urine were collected. The same screening was performed at discharge from hospital after allogeneic HCT and in case of a new admission into our institution. In addition routine microbiological investigations such as bacterial cultures from blood, urine, swabs, stool or central venous catheters were performed whenever clinically needed. Multidrug-resistant gram negative bacteria were categorized as 4MRGN (resistant to cephalosporins, piperacillin, fluorochinolones and to carbapenems) or as 3MRGN (resistant to 3 of these 4 antimicrobial drug groups). The primary endpoint of this analysis was day 100 non relapse mortality (NRM). Secondary endpoints were NRM and overall survival (OAS) two years post HCT. RESULTS: 23 out of 72 patients (32%) were colonized by multidrug-resistant bacterial pathogens (MRP+ group) either at baseline (baseline MRP+ group, n=13, 18%) or at any other time point until day 100 post transplantation. Four patients were positive for two MRP either simultaneously at baseline (n=1) or at different time points (n=3). Detected MRP (n=27) were as follows: 3MRGN Escherichia coli or Klebsiella pneumonia (n=11), 4MRGN Pseudomonas aeruginosa (P. aeruginosa, n=4), 3MRGN P. aeruginosa (n=2), 4MRGN Stenotrophomonas maltophilia (n=1), 3MRGN Citrobacter freundii (n=1), VRE (n=7) and MRSA (n=1). Out of these 23 patients 7 patients developed an infection with MRP after HCT: Septicemia with 3MRGN Escherichia coli (n=3), septicemia with 3MRGN Klebsiella pneumonia (n=1), septicemia with P. aeruginosa (4 MRGN n=2, 3MRGN n=1) and one patient with VRE septicemia and 4MRGN P. aeruginosa pneumonia. Out of the 4 patients with multidrug-resistant P. aeruginosa infection three died transplant related (two of these patients had been already colonized with 4MRGN P. aeruginosa at baseline). However, 2-year OAS of MRP colonized versus non-colonized patients was essentially the same (66.6% versus 63.0%, median follow up 23.8 months range 7.0 to 48.0 months). Day 100 NRM was higher in the baseline MRP+ group and in the entire MRP+ group in comparison with non-multidrug-resistant bacterial pathogens colonized patients (23.1% and 17.4% versus 10.2%, not statistically significant [ns]). Data for 2 year NRM were 32.7%, 22.2% and 17.1% (ns), respectively. The increased NRM of MRP+ patients was mainly due to the high NRM of patients infected by multidrug resistant P. aeruginosa. CONCLUSIONS: Colonization or infection with 3MRGN gram negative non-P. aeruginosa enterobacteriaceae or by VRE has no negative impact on the outcome after allogeneic HCT. Thus allogeneic HCT of patients colonized by MRP is feasible. However, patients colonized by multidrug-resistant P. aeruginosa seem to have a dismal outcome. Allogeneic HCT of these patients should be considered with care. We therefore suggest to include screening for MRP in the pretransplant recipient work up particularly to identify patients colonized by multidrug-resistant P. aeruginosa. Disclosures No relevant conflicts of interest to declare.

Description: Interferon alpha (IFN) induces complete hematologic remission in 70% to 80% of patients with CML in early chronic phase, with up to 8–30% of cases achieving a complete cytogenetic response (CCR). Although patient responses correlate with Hasford and Sokal risk scores, the molecular basis for this heterogeneity remains poorly understood. We hypothesized that polymorphic differences in the IFN signal transduction cascade might account for different patient responses. IFN binds the heterodimeric type I interferon receptor, the two subunits of which are encoded by IFNAR1 and IFNAR2. Binding activates the JAK1 and TYK2 non-receptor tyrosine kinases, which phosphorylate and activate STAT proteins. We studied 187 cases treated with IFN based regimens as part of the German CML studies I-III. Of these, 105 were defined as non-responders (no cytogenetic response) and 82 as responders (achievement of

Description: FIP1L1-PDGFRA is a cytogenetically cryptic fusion gene seen in a minority of patients with chronic eosinophilic leukaemia (CEL). Observations in mice have suggested that FIP1L1-PDGFRA alone is insufficient to induce all features of the human disease, and that a secondary event associated with IL-5 overexpression may be required for the full phenotype. In this study we have investigated the hypothesis that constitutional genetic variation in IL-5 signalling may be associated with the development or severity of FIP1L1-PDGFRA positive CEL in humans. We genotyped six single nucleotide polymorphisms (SNP) within or close to the IL5RA or IL5 genes in 82 European patients with FIP1L1-PDGFRA positive CEL plus, as controls, healthy individuals (n=100), patients with FIP1L1-PDGFRA negative eosinophilia (n=100) or patients with chronic myeloid leukaemia (n=100). We found no association between SNP allele frequency between FIP1L1-PDGFRA positive and control cases. However for FIP1L1-PDGFRA cases, we found an association between the genotype at rs4054760, a SNP in the 5′UTR of IL5RA, and peripheral blood eosinophil count (P=0.026) as well as the presence or absence of tissue infiltration (P=0.032). Although these associations fell below the level of significance once corrected for multiple testing, no such association was seen in FIP1L1-PDGFRA negative cases and no difference in allele frequencies for rs4054760 was seen in control populations across Europe. Furthermore, in an analysis of 128 patients with CML, there was a trend towards lower expression of IL5RA expression in cases with a c/t or t/t genotype compared to those who were c/c (P=0.08). These data suggest that the constitutional IL5RA genotype may be associated with the severity of FIP1L1-PDGFRA disease.

Description: Systemic mastocytosis with an associated hematologic neoplasm (SM-AHN) is the most common subtype of advanced SM (advSM), diagnosed in up to 80% of patients. The AHN is most frequently diagnosed as a myeloid neoplasm, e.g., SM-MDS/MPNu or SM-CMML. Acquired mutations in KIT (usually KIT D816, KIT D816mut) are detectable in 〉90% of patients. The basis for the SM-AHN phenotype is usually the multi-lineage involvement, e.g. monocytes, eosinophils and other non-mast cell lineages, of KIT mutations. Core binding factor (CBF) positive AML (CBFpos AML) represents a distinct subtype and is identified in 5-8% of all AMLs. KIT mutations, most frequently KITD816mut, are detectable in up to 45% of CBFpos AML patients and are associated with an adverse prognosis. There is, however, only little information on KIT D816mut/CBFneg AML. We therefore evaluated a) clinical and molecular characteristics, b) response to treatment and, c) survival and prognostic factors in 40 KIT D816mut/CBFneg patients with histologically proven SM and associated AML (SM-AML), collected at 4 centers of the European Competence Network on Mastocytosis (ECNM). Molecular analyses (n=32) revealed at least one additional somatic mutation (median, n=3) apart from KIT D816, most frequently SRSF2 (n=12, 38%), RUNX1 (n=11, 34%), TET2 (n=11, 34%), ASXL1 (n=10, 31%), or NPM1 (n=7, 22%). At least one mutation in SRSF2, ASXL1 or, RUNX1 (S/A/Rpos) was identified in 21/32 (66%) patients. At diagnosis of SM-AML 21/40 (52%) patients had an aberrant karyotype. Secondary AML evolved in 29/40 (73%) patients from SM ± associated myeloid neoplasm and longitudinal molecular analyses revealed acquisition of new somatic mutations (TP53, n=2; NPM1, n=1; RUNX1, n=1, ASXL1, n=1; BCOR, n=1; IDH1/2, n=1) and/or karyotype evolution in 15/16 (94%) patients at the time of SM-AML. Thirty-one of 40 (78%) patients were treated with intensive chemotherapy (ICT) with a complete response (CR) rate of 40%. Allogeneic stem cell transplantation (SCT) was performed in 12/40 (30%) patients with durable CR in 6/12 (50%) patients. S/A/Rpos and/or the presence of a poor-risk karyotype were adverse predictive markers for response to treatment. To further investigate whether KITD816mut/CBFneg AMLdefines a distinct AML subtype associated with SM, two independent AML databases (AMLdatabases) were retrospectively screened and 69 KIT D816mut/CBFneg AML patients identified. The comparison between KIT D816mut/CBFneg SM-AML from ECNM (n=40) centers with KIT D816mut/CBFneg AMLdatabases(n=69) revealed remarkable similarities: a) a high KIT D816 variant allele frequency (VAF) (median 34% vs. 29%), b) with the exception of SRSF2 (38 vs. 18%), a highly similar mutation landscape, rather comparable to that of advSM (Jawhar et al., Blood 2017) than to that of de novo AML, c) in contrast to de novo AML, a low frequency of FLT3 mutations (3 vs. 7%), and d) a high frequency of an aberrant karyotype (52 vs. 42%). The median overall survival (OS) of 40 KIT D816mut/CBFneg SM-AML and 17 evaluable KIT D816mut/CBFneg AMLdatabases was 5.4 (95% confidence interval, CI [1.7-9.1]) and 26.4 (95% CI [0-61.0]) (P=0.015) months, respectively (Figure 1). However, if only the patients with ICT ± allogeneic SCT were compared, median OS between the two groupswas not different (16.7 vs. 26.4 months, P=0.4). In multivariate analyses, S/A/Rpos and a poor-risk karyotype remained the only independent poor-risk factors with regard to OS. These results were independent of treatment modalities. We conclude that KIT D816mut/CBFneg AML is a new poor-risk subtype associated with SM (SM-AML). The remarkable clinical, genetic and prognostic similarities between SM-AML and AMLdatabases suggest that a significant proportion of the AMLdatabases patients may in fact have SM-AML. We therefore strongly recommend to determine serum tryptase and KIT D816 mutation status in all AML patients, and to perform bone marrow histology in KIT D816mut patients. These simple diagnostic measures would allow reclassification to SM-AML and inclusion of KIT inhibitors in established treatment modalities of AML. Disclosures Meggendorfer: MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Döhner:Amgen: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; AROG Pharmaceuticals: Research Funding; Amgen: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding; Astellas: Consultancy, Honoraria; Celator: Consultancy, Honoraria; Bristol Myers Squibb: Research Funding; Celator: Consultancy, Honoraria; Sunesis: Consultancy, Honoraria, Research Funding; Seattle Genetics: Consultancy, Honoraria; Jazz: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; Astex Pharmaceuticals: Consultancy, Honoraria; AROG Pharmaceuticals: Research Funding; Astellas: Consultancy, Honoraria; Agios: Consultancy, Honoraria; Astex Pharmaceuticals: Consultancy, Honoraria; Agios: Consultancy, Honoraria; Bristol Myers Squibb: Research Funding; Jazz: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Pfizer: Research Funding; Pfizer: Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Seattle Genetics: Consultancy, Honoraria; Sunesis: Consultancy, Honoraria, Research Funding. Sperr:Novartis: Honoraria; Pfizer: Honoraria; Daiichi Sankyo: Honoraria. Valent:Incyte: Honoraria; Pfizer: Honoraria; Novartis: Honoraria. Reiter:Incyte: Consultancy, Honoraria.

Description: Systemic mastocytosis (SM) is a rare hematologic neoplasm characterized by abnormal growth and accumulation of tissue mast cells (MC) in various organ systems, including bone marrow (BM). Indolent and advanced forms of SM have been described. Whereas patients with ISM have a normal or near normal life-expectancy, patients with advanced SM, including those suffering from mast cell leukemia (MCL) have a poor prognosis. In these patients, neoplastic MC are usually resistant against conventional drugs and various targeted drugs. In rapidly progressive aggressive SM (ASM) and MCL, polychemotherapy followed by allogeneic hematopoietic stem cell transplantation (alloHCT) has been proposed. However, outcome of alloHCT in advanced SM is unknown, and it also remains uncertain whether clinically relevant graft-versus-SM (GVSM) effects may occur in these patients, as only sporadic case reports have been published. We performed a retrospective multi-center analysis to evaluate the outcome of alloHCT in patients with advanced SM. Fifty-four advanced SM patients receiving SCT in 32 transplantation centers in Europe and America were identified between 1990 and 2013. The median patient age was 45 years. Donors were: HLA identical siblings (31), unrelated donors (URD) (15), umbilical cord blood donors (UCB) (2), and haploidentical donors (1). In 5 patients, stem cell source was not defined (5). Thirty-four patients received myeloablative conditioning (MAC) and 18 received reduced intensity conditioning regimens (RIC). In 2 patients, conditioning regimen was not specified. Indications for alloHCT were SM with an associated clonal hematologic non-mast cell lineage disease (SM-AHNMD) (n=32), MCL (n=13, including one with MCL-AHNMD), 8 with ASM and 1 with myelomastocytic leukemia (MML). The most prevalent AHNMD was acute myeloid leukemia (AML, n=16). With follow-up of 35-6180 (median 365) days, SM responses (defined as ≥50% decrease in BM mast cells ± decrease in serum tryptase ± regression of other organ manifestations) were observed in 39 patients (72%), including complete responses (CR) documented in 12 patients (22%). Eleven patients had stable disease, whereas 4 patients (7%) progressed immediately after alloHCT (primary resistance). In addition, 10 patients progressed (5 of them within 100 days) after an initial response. Progression was most frequently seen in MCL patients (n=6, 50%). In the AHNMD group, only 8 patients relapsed/progressed (25%). The overall survival (OS) and SM progression-free survival (PFS) at 1 year were 63% and 50% for all patients, 77% and 68% for SM-AHNMD, 63% and 50% for ASM, and 25% and 17% for MCL, respectively. The strongest predictive variable associated with inferior survival was a diagnosis of MCL. Other factors associated with poor outcome were: Karnofsky performance status ≤70%, ≥2 SM regimens given before alloHCT (e.g., steroids, cladribine, chemotherapy, tyrosine kinase inhibitor), donor source (alternative donors-UCB and haploidentical compared to sibling or URD), SM progression within the first 100 days, normal cytogenetics (compared to t(8;21) (q22;q22), and RIC (compared to MAC). The following variables were not associated with poor outcome: patient and donor age, recipient-donor sex match status, graft source (BM vs. peripheral stem cells), BM mast cell percentage at time of alloHCT, and CR status of AML or SM response at time of alloHCT. This largest multi-center analysis of results in advanced SM provides evidence for clinical efficacy of alloHCT, presumably because of a GVSM effect of alloHCT (achieving CR, and response to donor-lymphocyte infusions and RIC alloHCT). However, responses varied among different SM categories: while patients with SM-AHNMD enjoyed excellent outcomes, the OS for MCL patients in general, was poor. Nevertheless it is remarkable that 3 of 13 patients with MCL – an otherwise fatal disease with a median survival of

Description: The WHO classification (2008) defines "myeloid/lymphoid neoplasm with eosinophilia and rearrangement of PDGFRA, PDGFRB or FGFR1" as a rare subtype of myeloid neoplasms. Whilst patients with PDGFRA or PDGFRB rearrangements respond very well to imatinib, the optimal therapy for patients with FGFR1 rearrangements, which we refer to as FGFR1 fusion gene positive MLN-eo (FGFR1+ MLN-eo), remains to be defined. Encouraging in-vitro data using inhibitors of the FGFR1 tyrosine kinase prompted the implementation of ponatinib, which inhibits FGFR1, into therapeutical strategies. In a recent report, the clinical activity of ponatinib was reported in a single patient who concomitantly received high-dose chemotherapy and allogeneic stem cell transplantation (ASCT, Khodadoust et al, Leukemia 2015). We sought to evaluate efficacy of ponatinib in seven consecutive FGFR1+ MLN-eo patients. Median age was 52 years (range, 48-74) with a male predominance (n=5). Median observation time after diagnosis was 10 months (range, 5-36). All patients presented with left-shifted leukocytosis but only three patients [all with t(8;13)] had eosinophilia of 〉0.5 x 109/l. Bone marrow biopsy revealed a hypercellular marrow consistent with myeloproliferative neoplasm in all patients. Five patients presented with concomitantly diagnosed lymphoid neoplasms, i.e. T-lymphoblastic lymphoma (T-LBL, n=3), biclonal accelerated phase (n=1) or lymphoid blast phase of MPN/B-cell acute lymphoblastic leukemia (B-ALL, n=1). Cytogenetic analysis revealed a reciprocal translocation with involvement of chromosome band 8p11 in all patients [t(8;13)(p11;q12), n=3; t(8;22)(p11;q11), n=2; t(1;8;22)(?;p11;q11), n=1; t(6;8)(q27;p11), n=1]. On molecular level, RT-PCR identified the associated fusion genes ZMYM2-FGFR1 (n=3), BCR-FGFR1 (n=3), and FGFR1OP-FGFR1 (n=1), respectively. In one patient with T-LBL, the FGFR1 rearrangement was revealed by FISH analysis in 80% of lymph node cells indicating an origin of both MPN and T-LBL from the same progenitor/stem cell (myeloid/lymphoid stem cell neoplasm) and T-LBL as a feature of extramedullary lymphoid blast phase. All patients were initially treated with chemotherapy-based regimens including hydroxyurea (n=4) and/or high-dose chemotherapy (n=3), the latter exclusively in patients with concomitant aggressive lymphoid neoplasms. Lack of complete response, e.g. persisting features of MPN, relapse or progression led to the off-label use of ponatinib at a dose of 30mg/day (n=2) or 45mg/day (n=5). Median duration of treatment was 8 weeks (range, 2-52). A temporary partial hematologic response (control of peripheral blood cell count) was observed in 6 of 7 patients. One patient did not respond at all and died within a few weeks while on ponatinib due to progressive disease. Three of the 6 responders had cytogenetic analysis at a median of 3 months after the start of ponatinib. One patient with t(8;13) achieved a partial cytogenetic response (50% of metaphases positive after 3 months of treatment); in all other patients no cytogenetic response was observed. Four patients underwent ASCT and are in complete molecular remission and alive after a median time of 19 months (range, 8-36) after diagnosis and 13 months (range, 4-29) after ASCT. For one patient with BCR-FGFR1-positive MLN-eo without concomitant lymphoid disease ASCT is planned. One patient is on supportive care. Conclusion: Unexpectedly, response to standard dose ponatinib in FGFR1+ MLN-eo has been poor. There was either progressive disease or no evidence for sustained hematologic or cytogenetic response. However, there was also no evidence for a sustained complete remission on intensive chemotherapy in patients with full myeloid/lymphoid phenotype. Hence, ASCT currently remains the only option to achieve long-term remission and possibly cure in FGFR1+ MLN-eo. Disclosures Off Label Use: ponatinib, used as FGFR1 inhibitor. Bommer:Alexion Pharmaceuticals: Honoraria. Cross:Ariad: Consultancy, Honoraria, Research Funding; Qiagen: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Hochhaus:Bristol-Myers Squibb: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; ARIAD: Honoraria, Research Funding.

Description: Multidrug-resistant bacterial pathogens (MRP) such as extended-spectrum beta-lactamase producing enterobacteriaceae (ESBL), vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA) and multi-resistant Pseudomonas aeruginosa (P. aeruginosa) are an emerging challenge in allogeneic hematopoietic cell transplantation (HCT). However, no comprehensive data are available on the prevalence of MRP, their impact on the outcome after HCT and on the probability to clear a MRP. It was the purpose of this study to systematically analyze the issue of MRP in HCT. PATIENTS AND METHODS: From 07/2010 to 12/2015 a total number of 121 (43 F; 78 M) consecutive patients who received the first allogeneic HCT at our institution were analyzed retrospectively. As baseline investigation before conditioning all patients underwent a comprehensive screening for MRP. Swabs from nose, throat, axilla, urethra and anus as well as samples from stool and urine were collected. During the course of transplantation surveillance cultures were performed weekly. In addition, routine microbiological investigations were done from blood, urine, swabs, stool or central venous catheters whenever clinically needed. In MRP colonized patients surveillance stool specimen were taken until the MRP was repeatedly non-detectable. Multidrug-resistant gram neg. bacteria were categorized as 4MRGN (resistant to cephalosporins, piperacillin, fluorochinolones and carbapenems) or as 3MRGN (resistant to 3 of these 4 antimicrobial drug groups). The primary endpoint of this analysis was day 100 non relapse mortality (NRM). Secondary endpoints were NRM and overall survival (OS) after 2 years. A further endpoint in MRP+ patients was the time to non-detectability of the MRP. RESULTS: The patient characteristics were as follows: Underlying diseases were AML (62), ALL (7), CML (8), MPN (5), lymphoma (9), MDS (25), and multiple myeloma (5). The conditioning regimen was myeloablative in 50, reduced intensity in 71 patients. Patients were transplanted with peripheral blood stem cells (105) or bone marrow (16) from matched siblings (28), matched unrelated (67), mismatched (15) or haploidentical donors (11). 33 patients (27%) were colonized by at least one MRP (MRP+ group) either at baseline (baseline MRP+ group, n=18, 15%) or at any other time point until day 100 post HCT. The 33 MRP+ group patients were colonized by 42 MRP (baseline MRP+ group: 19 MRP). Detected MRP were 3MRGN E. coli or Klebsiella pneumonia (17), 4MRGN (9) or 3MRGN (2) P. aeruginosa, multi-resistant Stenotrophomonas maltophilia (2), 3MRGN Citrobacter freundii (1), 3MRGN Acinetobacter baumanii (1), 4MRGN Enterobacter cloacae (2), VRE (7) and MRSA (1). Out of these 33 patients 12 (36%) developed an infection with an MRP after HCT: septicemia (n=9), pneumonia caused either by 3MRGN Klebsiella (n=1) or by 4MRGN P. aeruginosa (n=1) and urinary tract infection by 4MRGN Enterobacter cloacae (n=1). 5 patients died MRP related due to septicemia (4MRGN P. aeruginosa n=4, VRE n=1). However, day 100 and 2-year NRM of MRP colonized vs non-colonized patients were essentially the same: 15 and 21% vs 15 and 24%, respectively. Even for the baseline MRP+ group there was no significant difference of NRM: 17 and 29% vs 15 and 22%. Overall survival was also not impaired in the MRP+ group 2 years post HCT (median follow up 32.4 months, range 7.5 to 71.4 months): MRP colonized versus non-colonized patients: 60 vs 55% (baseline MRP+ group 54 vs 58%). Out of the 33 MRP+ group patients 21 patients were able to clear the MRP. On day 100 after HCT 36% of patients had been able to clear the MRP. Median time to non-detectability of the MRP was 6.3 months. In 12 patients the MRP did not disappear until the end of the observation period or death (median follow up 15 months). There was a highly significant (p

Description: Central venous catheters (CVCs) are extensively used in patients undergoing hematopoietic cell transplantation (HCT) or induction chemotherapy for acute leukemia. In these patients CVCs are placed routinely either via internal jugular (IJV) or subclavian veins (SCV). Several studies have compared rates of complications between both insertion sites, particularly in the intensive care unit setting. However, to our knowledge there are no data in the literature comparing the insertion sites IJV versus SCV in patients undergoing allogeneic HCT or high dose therapy for hematologic malignancies. Thus, it was the purpose of this study to analyze systematically complications of CVCs at the different insertion sites in these patients. Patients and methods: All consecutive patients who were treated in the unit for adult HCT at our institution from 01/2011 to 06/2013 were included into this retrospective analysis. Inclusion criterion was insertion of a CVC due to allogeneic HCT, autologous HCT or induction therapy for AML or ALL. 3-lumen standard CVCs (Arrow, Reading, PA) were placed after informed consent either via the IJV or the SCV. CVCs were inserted by experienced physicians after disinfection by 70% propanolol under full barrier precautions. The insertion site was chosen at the responsible physician´s own discretion. CVCs were covered by chlorhexidine gluconate impregnated dressings, either as transparent polyurethane (Tegaderm CHG, 3M, Saint Paul, MN) or as sponge dressing (Biopatch, Ethicon, Cincinnati, OH). No patient received a systemic antibiotic prophylaxis. Reasons for premature removal of CVCs were suspected or proven CVC-related blood stream infection (BSI), progression of local infections at the insertion site, or any other CVC related severe adverse event. End points of this study were local infections, fever, BSI, duration of catheterization per CVC, congestion of the CVC, thrombosis, pneumothorax and suspected or proven catheter related deaths. Results: During the study period 255 CVCs were placed in 170 consecutive patients [median age: 59 years (range 19-79), F: n=63; M: n=107] due to allogeneic HCT (65 patients, 101 insertions), autologous HCT (30 patients, 33 insertions) or induction therapy for AML or ALL (75 patients, 121 insertions). Underlying diseases were AML (n=102), ALL (n=9), MDS (n=15), MPN (n=4), lymphoma (n=21) or plasma cell neoplasia (n=19). Out of the 255 CVSs 155 (61%) were sited via the IJV and 100 (39%) via the SCV. Among the 101 CVCs in the allogeneic HCT group 60 (60%) were placed in the IJV and 41 (41%) in the SCV. The median duration of catheterization/per CVC for the entire group was 16 days (range 3-49, IJV: 17, SCV: 15 days, ns). The corresponding data for the allogeneic HCT group were 18 (IJV) and 17 day (SCV). The events fever or local infection occurred in 75% (45/60) of IJV- and in 95% (39/41) of SCV-CVCs (p=0.0084) in the allogeneic HCT group. Moreover, in SCV-CVCs these events arose significantly earlier (median time to event 7 vs. 10 days in the IJV (p=0.012). Focusing only on the event local infection the results were also superior for the IJV-CVCs: 28/60 (47%) vs. 29/41(71%) for SCV-CVCs (p=0.026). For the entire cohort of CVCs data were similar: The events fever or local infection occurred in 127/155 (82%) of IJV- and 95/100 (95%) of SCV-CVCs (p=0.025). Median time to these events were 8 (IJV) vs. 10 days (SCV, p=0.0009). For local infections alone the differences were even more pronounced: 81/155 (IJV: 52%) vs. 81/100 (SCV: 81%, p

Description: Recent evidence has demonstrated that acquired uniparental disomy (aUPD) is a novel mechanism by which pathogenetic mutations in cancer may be reduced to homozygosity. As a route towards identifying novel mutations in myeloproliferative neoplasms (MPN), we performed a genome wide single nucleotide polymorphism (SNP) screen to identify aUPD in 58 patients with atypical chronic myeloid leukemia (aCML; n=30), JAK2 mutation negative myelofibrosis (MF; n=18) or JAK2 mutation negative polycythaemia vera (PV; n=10). Stretches of homozygous, copy neutral SNP calls 〉20Mb were seen in 10 (33%) aCML, 1 (6%) MF but absent in PV. In total seven different chromosomes were involved with 7q and 11q each affected in 3 (10%) of aCML cases and 1p, 13, 17q, 20q, 21q involved in single individuals. The 1p and 13 abnormalities were associated with homozygous mutations in MPL and FLT3, respectively. To characterize the two recurrent regions at 7q and 11q, we focused on genes encoding intracellular signal transduction components because of the known association between MPNs and deregulated tyrosine kinase signaling. No mutations were detected in MET, EPHA1, EPHB6 or BRAF but homozygous CBL missense mutations were found in all three cases with 11q aUPD. To determine the prevalence of CBL mutations, we sequenced exons 8 and 9 in an additional 574 MPN cases. A total of 27 sequence variants were identified in 26 patients of whom 3 had MF, 10 had CMML, 12 had aCML/MPD-U and one had HES/CEL. Microsatellite analysis across 11q indicated significant tracts of 11q copy neutral homozygosity in 11/26 CBL mutated cases. In two cases, CBL mutations were acquired as secondary events during progression of a pre-existing MPN. Patients with CBL mutations had a shorter overall survival and progression-free survival compared to mutation negative cases (OS: 33 months vs 39 months; PFS: 22 months vs 32 months) but the differences were not significant. Similarly there was no difference in gender, age, white cell count or percentage of eosinophils between mutation positive and mutation negative cases. CBL plays both positive and negative roles in tyrosine kinase signal transduction by acting as an adaptor and also a ubiquitin ligase. Of the 27 variants, 21 (78%) were missense substitutions (15 different mutations) in the region encoding the RING or linker domains, 5 (19%) were candidate splicing abnormalities involving exon 8 and one (3%) produced a stop codon. Functional analysis of selected mutations demonstrated that they abrogated CBL ubiquitin ligase activity and were transforming as assessed by the ability to confer a proliferative advantage in both liquid and semi-solid cultures of Ba/F3-FLT3 cells. We conclude that acquired, inactivating CBL mutations are a novel and widespread pathogenetic abnormality in morphologically-related, aggressive MPNs.

Description: Derivative chromosome 9 deletions are seen in 10% to 15% of patients with chronic myelogenous leukemia and have been associated with a poor prognosis; however, no studies have been performed in the context of a randomized clinical trial. We developed a DNA-based deletion screen and investigated 339 chronic phase patients treated with interferon-α as first-line therapy in 3 controlled German studies with a median observation time of 7 years. Deletions were detected in pretreatment DNA of 59 of 339 (17%) patients. Of these, 21 spanned the ABL/BCR junction and 38 were centromeric (n = 20) or telomeric (n = 18) of the breakpoint. There was no significant difference in overall survival between deleted and nondeleted patients. Patients with breakpoint-spanning deletions had poorer survival compared with patients without deletions (4.7 versus 7.8 years; P = .003), but this was not significant when censored at allogeneic stem cell transplantation (n = 129) or imatinib (n = 62) treatment in the first chronic phase (P = .078). Unexpectedly, deletions that did not span the breakpoint were associated with improved survival compared with cases without deletions (P = .001). Multiple Cox regression analysis indicated that deletion status (P = .007), age (P = .018), and spleen enlargement (P 〈 .001) were significant independent indicators of survival and confirmed that only deletions spanning the ABL/BCR breakpoint were associated with an adverse prognosis (P = .039).