Impact of early cyclosporine A levels on acute graft-versus-host disease in allogeneic hematopoietic stem cell transplantation using in vivo T-cell depletion

BACKGROUND AIMS

Cyclosporin A (CsA) remains a major component of immunosuppressive regimens applied in allogeneic hematopoietic stem cell transplantation (HSCT). The impact of CsA trough levels during the first weeks after HSCT has not yet been investigated specifically in anti-T-lymphocyte globulin (ATLG)-based HSCT from matched related and unrelated donors.

METHODS

To address this issue, we have retrospectively examined 307 consecutive matched related (n = 145) and unrelated (n = 162) HSCTs, using peripheral blood stem cells or bone marrow. HSCTs for active, uncontrolled malignancies were excluded. The initial three weeks' average mean CsA trough levels were analyzed in landmark and multi-state models, using a cut-off of 200 ng/mL.

RESULTS

CsA levels >200 ng/mL were associated with a reduced risk of acute graft-versus-host disease (GVHD) grade 3-4 at the first-week landmark (subdistribution hazard ratio [SHR] 0.59, P = 0.03) and the second-week landmark (SHR 0.48, P = 0.004), whereas there was no impact at the third-week landmark (HR 0.87, P = 0.69). This was supported by a multi-state model, in which week 1 (hazard ratio [HR] 0.53, P = 0.006) and week 2 (HR 0.48, P = 0.003), but not week 3 (HR 0.80, P = 0.44) CsA levels >200 ng/mL were associated with a reduced acute GVHD 3-4 risk. Relapse incidence was not significantly affected by week 1 through 3 CsA levels. Despite ATLG's inherent GVHD-preventive properties, week 1 CsA trough levels >200 ng/mL following ATLG-based HSCT (n = 220) were associated with a significantly reduced risk of non-relapse mortality (SHR 0.52, P = 0.02) and improved overall survival (HR 0.61, P = 0.02).

CONCLUSIONS

Our findings emphasize the continuing importance of ensuring CsA levels ≥200 ng/mL immediately post-transplant in the setting of ATLG-based HSCT.

ROP-ET: a prospective phase III trial investigating the efficacy and safety of ropeginterferon alfa-2b in essential thrombocythemia patients with limited treatment options

Interferon-based therapies, such as ropeginterferon alfa-2b have emerged as promising disease-modifying agents for myeloproliferative neoplasms (MPNs), including essential thrombocythemia (ET). Current ET treatments aim to normalize hematological parameters and reduce the thrombotic risk, but they do not modify the natural history of the disease and hence, have no impact on disease progression. Ropeginterferon alfa-2b (trade name BESREMi®), a novel, monopegylated interferon alfa-2b with an extended administration interval, has demonstrated a robust and sustained efficacy in polycythemia vera (PV) patients. Given the similarities in disease pathophysiology and treatment goals, ropeginterferon alfa-2b holds promise as a treatment option for ET. The ROP-ET trial is a prospective, multicenter, single-arm phase III study that includes patients with ET who are intolerant or resistant to, and/or are ineligible for current therapies, such as hydroxyurea (HU), anagrelide (ANA), busulfan (BUS) and pipobroman, leaving these patients with limited treatment options. The primary endpoint is a composite response of hematologic parameters and disease-related symptoms, according to modified European LeukemiaNet (ELN) criteria. Secondary endpoints include improvements in symptoms and quality of life, molecular response and the safety profile of ropeginterferon alfa-2b. Over a 3-year period the trial assesses longer term outcomes, particularly the effects on allele burden and clinical outcomes, such as disease-related symptoms, vascular events and disease progression. No prospective clinical trial data exist for ropeginterferon alfa-2b in the planned ET study population and this study will provide new findings that may contribute to advancing the treatment landscape for ET patients with limited alternatives. TRIAL REGISTRATION: EU Clinical Trials Register; EudraCT, 2023-505160-12-00; Registered on October 30, 2023.

Allogeneic Stem Cell Transplantation in Multiple Myeloma: Risk Factors and Outcomes in the Era of New Therapeutic Options-A Single-Center Experience

BACKGROUND

Despite major treatment advances, multiple myeloma remains incurable. The outcome of patients who are refractory to immunomodulatory agents, proteasome inhibitors, and anti-CD38 monoclonal antibodies is poor, and improved treatment strategies for this difficult-to-treat patient population are an unmet medical need.

METHODS

This retrospective, unicentric analysis included 38 patients with relapsed/refractory multiple myeloma or plasma cell leukemia who underwent allogeneic stem cell transplantation (allo-HSCT) between 2013 and 2022. Survival outcomes, relapse incidence, and non-relapse mortality were calculated according to remission status, date of allo-HSCT, cytogenetic risk status, timing, and number of previous autologous HSCTs.

RESULTS

The median PFS was 13.6 months (95% CI, 7.7-30.4) and the median OS was 51.4 months (95% CI, 23.5-NA) in the overall cohort. The cumulative incidence of relapse at 3 years was 57%, and non-relapse mortality was 16%. The median PFS and OS were significantly longer in patients with very good partial remission (VGPR) or better compared to patients with less than VGPR at the time of allo-HSCT (mPFS 29.7 months (95% CI, 13.7-NA) vs. 6.5 months (95% CI, 2.6-17.0); p = 0.009 and mOS not reached vs. 18.6 months (95% CI, 7.0-NA); p = 0.006).

CONCLUSION

For selected patients, allo-HSCT may result in favorable overall survival, in part by providing an appropriate hemato-immunological basis for subsequent therapies.

BendaEAM versus BEAM as conditioning regimen for ASCT in patients with relapsed lymphoma (BEB): a multicentre, randomised, phase 2 trial

Background

Replacement of carmustine (BCNU) in the BEAM regimen (BCNU, etoposide, cytarabine, melphalan) with bendamustine (BendaEAM) before autologous stem cell transplantation (ASCT) is feasible in lymphoma. However, randomised trials are lacking. Here, we present the first trial addressing this topic.

Methods

This multicentre, randomised, phase 2 study (BEB-trial) conducted at four haematological centres in Austria and Switzerland compares BEAM with BendaEAM in patients with relapsed lymphoma. Both regimens were administered intravenously before ASCT, in BEAM according to the standard protocol (300 mg/m2 BCNU on day -6), in BendaEAM, BCNU was replaced by 200 mg/m2 bendamustine given on days -7 and -6. Eligible patients were aged 18-75 years and had mantle cell lymphoma, diffuse large B-cell lymphoma, or follicular lymphoma in first or second remission or chemosensitive relapse. The primary endpoint of the study was to evaluate whether replacement of BCNU by bendamustine reduces lung toxicity, defined as a decrease of the diffusion capacity of the lung for carbon monoxide by at least 20% at three months after ASCT. Data analyses were performed on an intention-to-treat basis. This study is registered with ClinicalTrials.gov, number NCT02278796, and is complete.

Findings

Between April 20, 2015, and November 28, 2018, 108 patients were enrolled; of whom 53 were randomly assigned to receive BendaEAM (36 male, 17 female) and 55 to receive BEAM (39 male, 16 female). All patients engrafted rapidly. Lung toxicity did not differ between groups (BendaEAM: n = 8, 19.5%; BEAM: n = 11, 25.6%; risk difference = -6.1%: 95% confidence interval: -23.9% to 11.7%). Acute toxicities of at least grade 3 were comparable in both groups (BendaEAM: 35.8%, BEAM: 30.9%). Overall survival (BendaEAM: 92.5%, BEAM: 89.1%) and complete remission (BendaEAM: 76.7%, BEAM: 74.3%) after 1 year (median follow-up: 369 days) were similar. No difference in quality of life was observed.

Interpretation

Results were similar for both regimens in terms of survival and response rates. A phase 3 non-inferiority study is required to investigate whether BendaEAM can be considered as an alternative to BEAM.

Funding

Mundipharma.

Successful SARS-CoV-2 mRNA Vaccination Program in Allogeneic Hematopoietic Stem Cell Transplant Recipients-A Retrospective Single-Center Analysis

(1) Background: mRNA COVID-19 vaccines are effective but show varied efficacy in immunocompromised patients, including allogeneic hematopoietic stem cell transplant (HSCT) recipients. (2) Methods: A retrospective study on 167 HSCT recipients assessed humoral response to two mRNA vaccine doses, using the manufacturer cut-off of ≥7.1 BAU/mL, and examined factors affecting non-response. (3) Results: Twenty-two percent of HSCT recipients failed humoral response. Non-responders received the first vaccine a median of 10.2 (2.5-88.9) months post-HSCT versus 35.3 (3.0-215.0) months for responders (p < 0.001). Higher CD19 (B cell) counts favored vaccination response (adjusted odds ratio (aOR) 3.3 per 100 B-cells/microliters, p < 0.001), while ongoing mycophenolate mofetil (MMF) immunosuppression hindered it (aOR 0.04, p < 0.001). By multivariable analysis, the time from transplant to first vaccine did not remain a significant risk factor. A total of 92% of non-responders received a third mRNA dose, achieving additional 77% seroconversion. Non-converters mostly received a fourth dose, with an additional 50% success. Overall, a cumulative seroconversion rate of 93% was achieved after up to four doses. (4) Conclusion: mRNA vaccines are promising for HSCT recipients as early as 3 months post-HSCT. A majority seroconverted after four doses. MMF usage and low B cell counts are risk factors for non-response.

TOP-PIC: a new tool to optimize pharmacotherapy and reduce polypharmacy in patients with incurable cancer

PURPOSE

Polypharmacy is a significant problem in patients with incurable cancer and a method to optimize pharmacotherapy in this patient group is lacking. Therefore, a drug optimization tool was developed and tested in a pilot test.

METHODS

A multidisciplinary team of health professionals developed a "Tool to Optimize Pharmacotherapy in Patients with Incurable Cancer" (TOP-PIC) for patients with a limited life expectancy. The tool consists of five sequential steps to optimize medications, including medication history, screening for medication appropriateness and drug interactions, a benefit-risk assessment using the TOP-PIC Disease-based list, and shared decision-making with the patient. For pilot testing of the tool, 8 patient cases with polypharmacy were analyzed by 11 oncologists before and after training with the TOP-PIC tool.

RESULTS

TOP-PIC was considered helpful by all oncologists during the pilot test. The median additional time required to administer the tool was 2 min per patient (P < 0.001). For 17.4% of all medications, different decisions were made by using TOP-PIC. Among possible treatment decisions (discontinuation, reduction, increase, replacement, or addition of a drug), discontinuation of medications was the most common. Without TOP-PIC, physicians were uncertain in 9.3% of medication changes, compared with only 4.8% after using TOP-PIC (P = 0.001). The TOP-PIC Disease-based list was considered helpful by 94.5% of oncologists.

CONCLUSIONS

TOP-PIC provides a detailed, disease-based benefit-risk assessment with recommendations specific for cancer patients with limited life expectancy. Based on the results of the pilot study, the tool seems practicable for day-to-day clinical decision-making and provides evidence-based facts to optimize pharmacotherapy.

Impact of the Recipient's Pre-Treatment Blood Lymphocyte Count on Intended and Unintended Effects of Anti-T-Lymphocyte Globulin in Allogeneic Hematopoietic Stem Cell Transplantation

Background: In allogeneic hematopoietic stem cell transplantation (HSCT), Anti-T-Lymphocyte Globulin (ATLG) may be used for the prevention of severe graft-versus-host disease (GVHD). ATLG targets both the recipient's lymphocytes and those transferred with the graft. Assuming an inverse relation between the recipient's absolute lymphocyte count (ALC) and exposure of remaining ATLG to the graft, we aim to evaluate the impact of the recipient's ALC before the first ATLG administration on the benefits (prevention of GVHD and GVHD-associated mortality) and potential risks (increased relapse incidence) associated with ATLG. Methods: In recipients of HLA-matched, ATLG-based HSCT (n = 311), we assessed the incidence of acute GVHD, GVHD-related mortality and relapse, as well as other transplant-related outcomes, in relation to the respective ALC (divided into tertiles) before ATLG. Results: The top-tertile ALC group had a significantly increased risk of aGVHD (subhazard ratio (sHR) 1.81; [CI 95%; 1.14-2.88]; p = 0.01) and aGVHD-associated mortality (sHR 1.81; [CI 95%; 1.03-3.19]; p = 0.04). At the highest ATLG dose level (≥45 mg/kg), recipients with lowest-tertile ALC had a trend towards increased relapse incidence (sHR 4.19; [CI 95%; 0.99-17.7]; p = 0.05, n = 32). Conclusions: ATLG dosing based on the recipient's ALC may be required for an optimal balance between GVHD suppression and relapse prevention.

Adverse impact of a high CD4/CD8 ratio in the allograft may be overcome by methotrexate- but not mycophenolate- or posttransplant cyclophosphamide-based graft versus host disease prophylaxis

INTRODUCTION

A high CD4/CD8 T cell ratio in hematopoietic stem cell transplant (HSCT) allografts was observed to predict graft-versus-host disease (GVHD) and non-relapse mortality (NRM) but has not been comparatively examined in settings of various GVHD-prophylaxis regimens.

METHODS

This retrospective monocentric study included all consecutive HSCT performed with peripheral blood stem cells (PBSC) between January 2000 and June 2021. The impact of the graft CD4/CD8 ratio was analyzed in three cohorts with different GVHD-prophylaxis platforms.

RESULTS

In the cyclosporine/mycophenolate-mofetil (CSA/MMF) cohort (n = 294, HLA-matched HSCT), a high (> 75^th percentile) CD4/CD8 ratio was associated with increased overall mortality (HR 1.56; P=0.01), increased NRM (HR 1.85; P=0.01) and GVHD-associated mortality (HR 2.13; P=0.005). In the post-transplant cyclophosphamide (PTCy)/tacrolimus/MMF cohort (n = 113, haploidentical-related or mismatched-unrelated HSCT), a high CD4/CD8 ratio was associated with increased overall mortality (HR 2.07; P=0.04) and aGVHD3-4 (HR 2.24; P=0.02). By contrast, in the CSA/methotrexate (CSA/MTX) cohort (n = 185, HLA-matched HSCT) the CD4/CD8 ratio had no significant impact on any of the investigated endpoints.

CONCLUSION

A high CD4/CD8 ratio in the allograft has an adverse impact on GVHD and survival in CSA/MMF- and PTCy-based HSCT, while MTX-based prophylaxis may largely alleviate this important risk factor.

Impact of first-line use of caplacizumab on treatment outcomes in immune thrombotic thrombocytopenic purpura

BACKGROUND

The von Willebrand factor-directed nanobody caplacizumab has greatly changed the treatment of immune thrombotic thrombocytopenic purpura (iTTP) in recent years. Data from randomized controlled trials established efficacy and safety.

OBJECTIVES

This study aims to address open questions regarding patient selection, tailoring of therapy duration, obstacles in prescribing caplacizumab in iTTP, effect on adjunct treatment, and outcomes in the real-world setting.

METHODS

We report retrospective, observational cohorts of 113 iTTP episodes treated with caplacizumab and 119 historical control episodes treated without caplacizumab. We aggregated data from the caplacizumab phase II/III trials and real-world data from France, the United Kingdom, Germany, and Austria (846 episodes, 396 treated with caplacizumab, and 450 historical controls).

RESULTS

Caplacizumab was efficacious in iTTP, independent of the timing of therapy initiation, but curtailed the time of active iTTP only when used in the first-line therapy within 72 hours after diagnosis and until at least partial ADAMTS13-activity remission. Aggregated data from multiple study populations showed that caplacizumab use resulted in significant absolute risk reduction of 2.87% for iTTP-related mortality (number needed to treat 35) and a relative risk reduction of 59%.

CONCLUSION

Caplacizumab should be used in first line and until ADAMTS13-remission, lowers iTTP-related mortality and refractoriness, and decreases the number of daily plasma exchange and hospital stay. This trial is registered at www.

CLINICALTRIALS

gov as #NCT04985318.

Secreted mutant calreticulins as rogue cytokines in myeloproliferative neoplasms

Mutant calreticulin (CALR) proteins resulting from a -1/+2 frameshifting mutation of the CALR exon 9 carry a novel C-terminal amino acid sequence and drive the development of myeloproliferative neoplasms (MPNs). Mutant CALRs were shown to interact with and activate the thrombopoietin receptor (TpoR/MPL) in the same cell. We report that mutant CALR proteins are secreted and can be found in patient plasma at levels up to 160 ng/mL, with a mean of 25.64 ng/mL. Plasma mutant CALR is found in complex with soluble transferrin receptor 1 (sTFR1) that acts as a carrier protein and increases mutant CALR half-life. Recombinant mutant CALR proteins bound and activated the TpoR in cell lines and primary megakaryocytic progenitors from patients with mutated CALR in which they drive thrombopoietin-independent colony formation. Importantly, the CALR-sTFR1 complex remains functional for TpoR activation. By bioluminescence resonance energy transfer assay, we show that mutant CALR proteins produced in 1 cell can specifically interact in trans with the TpoR on a target cell. In comparison with cells that only carry TpoR, cells that carry both TpoR and mutant CALR are hypersensitive to exogenous mutant CALR proteins and respond to levels of mutant CALR proteins similar to those in patient plasma. This is consistent with CALR-mutated cells that expose TpoR carrying immature N-linked sugars at the cell surface. Thus, secreted mutant CALR proteins will act more specifically on the MPN clone. In conclusion, a chaperone, CALR, can turn into a rogue cytokine through somatic mutation of its encoding gene.

Phase III MANIFEST-2: pelabresib + ruxolitinib vs placebo + ruxolitinib in JAK inhibitor treatment-naive myelofibrosis

Myelofibrosis (MF) is a clonal myeloproliferative neoplasm, typically associated with disease-related symptoms, splenomegaly, cytopenias and bone marrow fibrosis. Patients experience a significant symptom burden and a reduced life expectancy. Patients with MF receive ruxolitinib as the current standard of care, but the depth and durability of responses and the percentage of patients achieving clinical outcome measures are limited; thus, a significant unmet medical need exists. Pelabresib is an investigational small-molecule bromodomain and extraterminal domain inhibitor currently in clinical development for MF. The aim of this article is to describe the design of the ongoing, global, phase III, double-blind, placebo-controlled MANIFEST-2 study evaluating the efficacy and safety of pelabresib and ruxolitinib versus placebo and ruxolitinib in patients with JAKi treatment-naive MF. Clinical Trial Registration: NCT04603495 (ClinicalTrials.gov).

Alternate-day dosing of caplacizumab for immune-mediated thrombotic thrombocytopenic purpura

BACKGROUND

The anti-von Willebrand factor (VWF) nanobody caplacizumab directly prevents the fatal microthrombi formation in immune-mediated thrombotic thrombocytopenic purpura (iTTP), thereby adding a new therapeutic principle to the treatment of this disorder. However, real-world treatment modalities beyond clinical trials remain heterogeneous.

METHODS

Here, we describe the risks and benefits of an alternate-day dosing regimen for caplacizumab by thoroughly analyzing the timing and outcome of this approach in a retrospective cohort of 25 iTTP patients treated with caplacizumab at seven different medical centers in Austria and Germany between 2018 and 2021.

RESULTS

Alternate-day dosing of caplacizumab appeared feasible and led to persisting normal platelet counts in most patients. Five patients experienced iTTP exacerbations or relapses that led to the resumption of daily caplacizumab application. VWF activity was repeatedly measured in 16 of 25 patients and documented sufficient suppression by caplacizumab after 24 and 48 h in line with published pharmacodynamics.

CONCLUSION

Extension of caplacizumab application intervals from daily to alternate-day dosing may be safely considered in selected patients after 3 to 4 weeks of daily treatment. Earlier modifications may be discussed in low-risk patients but require close monitoring for clinical and laboratory features of thrombotic microangiopathy.

Relapse Protection Following Early Cytomegalovirus Reactivation after Hematopoietic Stem Cell Transplantation Is Limited to HLA-C Killer Cell Immunoglobulin-Like Receptor Ligand Homozygous Recipients

Although the risk for nonrelapse mortality (NRM) associated with early cytomegalovirus (CMV) reactivation (CMVR) after allogeneic hematopoietic stem cell transplantation (HSCT) is well established, debate is ongoing on whether CMVR may reduce the risk of primary disease relapse. The aim of this study was to evaluate relapse protection following early CMV reactivation after HSCT in the context of the recipient HLA-C killer cell immunoglobulin-like receptor ligands (KIRLs). In this retrospective bicentric study, 406 matched related or unrelated donor transplantations for acute myelogenous leukemia (AML) or myelodysplastic syndrome (MDS) were stratified by HLA-C KIRL group (homozygous versus heterozygous) and analyzed separately for the impact of early CMVR on the cumulative incidences of relapse, NRM, and acute and chronic graft-versus-host-disease (GVHD) using landmark and multistate analyses. By landmark analysis of patients alive and relapse-free at 45 days post-HSCT, HLA-C KIRL homozygous recipients (C1/1 or C2/2) had a lower risk of subsequent relapse if CMVR occurred before this landmark (subhazard ratio [sHR], 0.36; P = .002). In contrast, in HLA-C KIRL heterozygous (C1/2) recipients, early CMVR had no impact on subsequent relapse (sHR, 0.88; P = .63). NRM (sHR, 3.31; P < .001) and grade III-IV acute GVHD (sHR, 2.60; P = .04) were significantly increased after early CMVR in the homozygous cohort, but not in the heterozygous cohort (NRM: sHR, 1.23; P = .53; grade III-IV acute GVHD: sHR, 1.40; P = .50). Multivariable landmark analyses and a multistate model confirmed the limitation of the relapse-protective effect of early CMVR to the homozygous cohort. Chronic GVHD and overall survival were not influenced in neither cohort. An antileukemic effect of early CMVR after HSCT for AML/MDS was significant but strictly limited to recipients homozygous for HLA-C KIRL. However, particularly in this cohort, CMVR had an adverse impact on aGVHD and NRM.

Austrian recommendations for the management of essential thrombocythemia

According to the World Health Organization (WHO) classification, essential (primary) thrombocythemia (ET) is one of several Bcr-Abl negative chronic myeloproliferative neoplasms (MPN). The classical term MPN covers the subcategories of MPN: ET, polycythemia vera (PV), primary myelofibrosis (PMF), and prefibrotic PMF (pPMF). ET is marked by clonal proliferation of hematopoietic stem cells, leading to a chronic overproduction of platelets. At the molecular level a JAK2 (Janus Kinase 2), calreticulin, or MPL mutation is found in the majority of patients. Typical ongoing complications of the disease include thrombosis and hemorrhage. Primary and secondary prevention of these complications can be achieved with platelet function inhibitors and various cytoreductive drugs including anagrelide, hydroxyurea and interferon. After a long follow up, in a minority of ET patients the disease transforms into post-ET myelofibrosis or secondary leukemia. Overall, life expectancy with ET is only slightly decreased.

Impact of platelets on major thrombosis in patients with a normal white blood cell count in essential thrombocythemia

Objectives

Cell counts have a significant impact on the complex mechanism of thrombosis in patients with essential thrombocythemia (ET). We recently demonstrated a considerable impact of white blood cell (WBC) counts on thrombotic risk in patients with optimized platelet counts by analysing a large anagrelide registry. In contrast, the current analysis of the registry aimed to estimate the influence of platelet counts on thrombotic risk in patients with optimized WBC counts.

Methods

Cox regression analysis and Kaplan‐Meier plot were applied on all patients in the registry with optimized WBC counts.

Results

By using the calculated cut‐off of 593 G/L for platelets, Cox regression analysis revealed a clear influence of elevated platelet counts on the occurrence of a major thrombotic event (P < .001). A Kaplan‐Meier plot revealed a markedly shorter time to a major thrombotic event for patients with platelet counts above the cut‐off (P < .001).

Conclusions

The data show clear impact of platelet lowering on the thrombotic risk in ET patients with normal WBC counts. Therefore, selective platelet lowering with anagrelide appears sufficient for thrombotic risk reduction in WHO‐diagnosed ET patients lacking leukocytosis.

Two common polymorphic variants of OATP4A1 as potential risk factors for colorectal cancer

Genetic variations in the organic-anion-transporting polypeptide (OATP)-encoding solute carrier of organic anions (SLCO) genes can promote cancer development and progression. The overexpression of solute carrier organic anion transporter family member 4A1 (OATP4A1), a transporter for steroid hormones, prostaglandins, and bile acids, has been previously associated with tumor recurrence and progression in colorectal cancer (CRC). Therefore, the present study aimed to investigate the association between 2 frequent single nucleotide polymorphisms (SNPs) in SLCO4A1 (rs34419428, R70Q; rs1047099G, V78I) and CRC predisposition. Following restriction fragment length polymorphism-PCR analysis in 178 patients with CRC [Union for International Cancer Control (UICC) stage I/II] and 65 healthy controls, no significant difference was observed in allele frequency and the number of heterozygous/homozygous individuals between the groups. Notably, the R70Q minor allele was identified to be associated with the V78I minor allele in the genome. Comparing of the individual genotypes of CRC patients to clinical data, including sex, UICC-stage and relapse revealed no increased risk for CRC. In addition, the OATP4A1 immunoreactivity assay in paraffin-embedded CRC and adjacent non-tumorous mucosa sections, examined using quantitative microscopy image analysis, did not reveal any association with these polymorphisms. No significant differences were observed in the expression levels, localization, and sodium fluorescein transport capacity among the OATP4A1 variants, which was studied using functional assays in Sf9-insect and A431 tumor cells overexpressing the 2 single and a double mutant OATP4A1 SNP variants. These results suggested that the 2 most frequent polymorphisms located in the first intracellular loop of OATP4A1 do not associate with CRC predisposition and tumor recurrence. They are unlikely to affect the outcome of CRC in patients.

A phase 1 study to evaluate the feasibility and efficacy of the addition of ropeginterferon alpha-2b to imatinib treatment in patients with chronic phase chronic myeloid leukemia (CML) not achieving a deep molecular response (molecular remission 4.5)-AGMT_CML 1

The goal of current management of patients with chronic phase chronic myeloid leukemia (CML) is to reach treatment-free remission with sustained deep molecular remission (DMR) being the prerequisite therefor. Second-generation tyrosine kinase inhibitors can induce deeper and faster remission than imatinib, but are often associated with severe adverse events (AEs). The combination of pegylated interferon (IFN) with imatinib was shown to induce higher molecular remissions than imatinib alone in two studies. Treatment discontinuation rates due to IFN induced AEs were high in both studies. To investigate safety, tolerability (primary objective), and efficacy (secondary objective) of the combination of imatinib with ropeginterferon alpha-2b this phase I study was initiated. Twelve patients were planned to be enrolled. Nine patients completed the study according to protocol. Three patients terminated the study early, one due to occurrence of a dose-limiting toxicity (neutropenia grade 3), one due to an AE (panic attacks grade 2) and one due to the patient's decision. Tolerability was good, non-hematologic AEs were mainly grade 1/2, hematologic AEs were mainly neutropenias. No new AEs were reported for the combination of imatinib and ropeginterferon alpha-2b. In a nondose-dependent manner the addition of ropeginterferon alpha-2b led to the achievement of a DMR in four out of nine patients after a treatment duration of 18 months. The combination of imatinib and ropeginterferon alpha-2b is safe and showed in this phase I study the ability to deepen the molecular response in patients with chronic phase CML not achieving a DMR with imatinib alone.

A multicenter retrospective evaluation of Chronic Myeloid Leukemia (CML) therapy in Austria assessing the impact of early treatment response on patient outcomes in a real-life setting : R-EFECT study

Background

Several clinical trials in chronic phase (CP) chronic myeloid leukemia (CML) showed that early response to tyrosine kinase inhibitor (TKI) treatment results in an improved long-term survival and progression-free survival. This study assessed whether patients achieving early treatment response (ETR; partial cytogenetic response or BCR-ABL1 mRNA ≤10% at 3 months) in daily practice also have a long-term survival benefit.

Methods

The Retrospective Evaluation of Early response in CML for long-term Treatment outcome (R-EFECT), a multicenter, retrospective chart review, documented patients with newly diagnosed CML-CP starting first-line TKI therapy in routine clinical practice. The primary aim was to assess the 5‑year overall survival rate.

Results

Of the 211 patients from 12 centers across Austria (January 2004–May 2010), 176 (median age, 56 years) were included in the analysis. All patients received first-line therapy with imatinib. Overall, 136 patients (77.3%) achieved ETR (ETR+ group), whereas 40 (22.7%) did not reach ETR (ETR− group). The ETR+ group had higher 5‑year overall survival (92.5% vs. 77.5%, P = 0.018) and progression-free survival (95.6% vs. 87.5%, P = 0.06) rates compared with the ETR− group. As expected, more patients in the ETR− group were switched to another TKI. At the last contact, 120 patients were still on imatinib and 44 had switched to another TKI (25 to nilotinib, 15 to dasatinib, and 4 to bosutinib).

Conclusion

The data are in line with randomized trials demonstrating that ETR is associated with improved survival and thus confirmed these results in patients treated in daily clinical routine.

SFRP1 promotor methylation analysis of FTA card touch-prep samples derived from colonic polyps

Whatman FTA® cards provide the most reliable method for DNA storage and extraction, however, the literature lacks reports on the epigenetic analysis of FTA card-derived tumor DNA. Therefore, this study aimed at demonstrating that punches from colonic adenoma samples preserved on FTA filter cards are suitable for methylation analysis by real-time methylation-specific PCR (MSP). Genomic DNA was isolated from a total of 40 sporadic colorectal adenoma samples stored on FTA cards for a median of 59.60 (range 48-72) months. After bisulfite treatment, deaminated DNA was analyzed by SYBR Green real-time MSP using primers specific for methylated and unmethylated promotor sequences of the secreted frizzled-related protein 1 (SFRP1) gene. Amplifiable DNA could be isolated from all FTA card punches while SFRP1 promotor methylation was present in 34/40 (85.0%) colorectal adenomas. Our results indicate that genomic DNA isolated from colonic tumor samples preserved on FTA cards is suitable for downstream methylation detection methodologies such as MSP even after prolonged storage periods.

A phase III randomized, multicentre, double blind, active controlled trial to compare the efficacy and safety of two different anagrelide formulations in patients with essential thrombocythaemia - the TEAM-ET 2·0 trial

Anagrelide is an established treatment option for essential thrombocythaemia (ET). A prolonged release formulation was developed with the aim of reducing dosing frequency and improving tolerability, without diminishing efficacy. This multicentre, randomized, double blind, active‐controlled, non‐inferiority trial investigated the efficacy, safety and tolerability of anagrelide prolonged release (A‐PR) over a reference product in high‐risk ET patients, either anagrelide‐naïve or ‐experienced. In a 6 to 12‐week titration period the individual dose for the consecutive 4‐week maintenance period was identified. The primary endpoint was the mean platelet count during the maintenance period (3 consecutive measurements, day 0, 14, 28). Of 112 included patients 106 were randomized. The mean screening platelet counts were 822 × 10⁹/l (95% confidence interval (CI) 707–936 × 10⁹/l) and 797 × 10⁹/l (95% CI 708–883 × 10⁹/l) for A‐PR and the reference product, respectively. Both treatments effectively reduced platelet counts, to mean 281 × 10⁹/l for A‐PR (95% CI 254–311) and 305 × 10⁹/l (95% CI 276–337) for the reference product (P < 0·0001, for non‐inferiority). Safety and tolerability were comparable between both drugs. The novel prolonged‐release formulation was equally effective and well tolerated compared to the reference product. A‐PR provides a more convenient dosing schedule and will offer an alternative to licensed immediate‐release anagrelide formulations.

Correction to: Ruxolitinib therapy formyelofibrosis in Austria : Consensus on therapy management

Correction to:Wien Klin Wochenschr 2018 https://doi.org/10.1007/s00508-018-1365-5 The original version of this article unfortunately contained a mistake. Table Nr. 1 was inconsistent. The corrected version of Table 1 is given below. We apologize for any inconveniences this may have ….

Ruxolitinib therapy for myelofibrosis in Austria : Consensus on therapy management

The oral Janus associated kinase (JAK1/2) inhibitor ruxolitinib has been available for treatment of patients with intermediate or high-risk myelofibrosis in Europe since 2012. Since its introduction, the expertise of prescribing doctors with respect to ruxolitinib function, efficacy and adverse effects has consistently been augmented, resulting in therapy modalities that are better tailored to individual patients as well as in increased safety of the treatment. The present consensus on ruxolitinib therapy management has been elaborated by Austrian experts in myeloproliferative neoplasms in line with international treatment guidelines. Our recommendations aim to contribute to an improved management of patients with myelofibrosis treated with ruxolitinib.

Austrian recommendations for the management of polycythemia vera

Polycythemia vera (PV) is a clonal disease arising from hematopoietic stem cells. Erythrocytosis is the hallmark of the disease but leukocytosis, thrombocytosis and splenomegaly may also be present. Thromboembolic complications occur in about 20% of patients. Circulatory disturbances as well as pruritus represent frequent symptoms of the disease. Mutations in the JAK2 gene are present in 95% of patients in exon 14 (V617F) and in 3% in exon 12. The main goal of the treatment for patients with PV is the prevention of thromboembolic events, transformation to myelofibrosis and acute myeloid leukemia. Interferon alpha and hydroxyurea are used as first-line treatment for high risk patients. For patients unresponsive to first-line therapy ruxolitinib is available.

Impact of white blood cells on thrombotic risk in patients with optimized platelet count in essential thrombocythemia

OBJECTIVES

Risk of thrombosis is significantly enhanced by both elevated platelet (PLT) and white blood cell (WBC) counts according to a retrospective analysis of a large anagrelide registry in thrombocythemic MPN patients. We were interested in the impact of elevated WBC counts on thrombosis risk in patients where PLT counts were reduced below the calculated cutoff of 574.5 G/L by treatment with anagrelide.

METHODS

Cox regression analysis and Kaplan-Meier plot were applied on all patients in the registry with optimized PLT counts.

RESULTS

Using the calculated cutoff of 9.66 G/L for WBC, Cox regression analysis revealed a clear influence of elevated WBC counts on the occurrence of a major thrombotic event (P = .012). A Kaplan-Meier plot revealed a markedly shorter time to a major thrombotic event for patients with WBC counts above the cutoff (P = .001).

CONCLUSIONS

These data suggest that additional correction of elevated WBC counts is mandatory in patients with optimally managed PLT counts to reduce thrombotic risk. This study is the first investigation in a prospectively observed large patient cohort which was treated homogenously allowing for evaluation of single parameters for an effect on thrombophilia.

Intensive consolidation with G-CSF support: Tolerability, safety, reduced hospitalization, and efficacy in acute myeloid leukemia patients ≥60 years

The aim of this study was to evaluate the efficacy and feasibility of intensified consolidation therapy employing fludarabine and ARA-C in cycle 1 and intermediate-dose ARA-C (IDAC) in cycles 2 through 4, in elderly acute myeloid leukemia (AML) patients and to analyze the effects of pegfilgrastim on the duration of neutropenia, overall toxicity, and hospitalization-time during consolidation in these patients. Thirty nine elderly patients with de novo AML (median age 69.9 years) who achieved complete remission (CR) after induction-chemotherapy were analyzed. To examine the effect of pegfilgrastim on neutropenia and hospitalization, we compared cycles 2 and 4 where pegfilgrastim was given routinely from day 6 (IDAC-P) with cycle 3 where pegfilgrastim was only administered in case of severe infections and/or prolonged neutropenia. All four planned cycles were administered in 23/39 patients (59.0%); 5/39 patients (12.8%) received 3 cycles, 3/39 (7.7%) 2 cycles, and 8/39 (20.5%) one consolidation-cycle. The median duration of severe neutropenia was 7 days in cycle 2 (IDAC-P), 11.5 days in cycle 3 (IDAC), and 7.5 days in cycle 4 (IDAC-P) (P < .05). Median overall survival was 1.1 years and differed significantly between patients aged <75 and ≥75 years (P < .05). The probability to be alive after 5 years was 32%. Together, intensified consolidation can be administered in AML patients ≥60, and those who are <75 may benefit from this therapy. Routine administration of pegfilgrastim during consolidation shortens the time of neutropenia and hospitalization in these patients.

Pre-fibrotic/early primary myelofibrosis vs. WHO-defined essential thrombocythemia: The impact of minor clinical diagnostic criteria on the outcome of the disease

The 2016 revised WHO criteria for the diagnosis of pre-fibrotic/early primary myelofibrosis (pre-PMF) require at least one of the following four borderline expressed minor clinical criteria: anemia, leukocytosis, elevated lactate dehydrogenase and splenomegaly. In this study, we evaluated the relative frequency of these four criteria in a group of 170 pre-PMF patients and compared them to 225 ET cases. More than 91% of pre-PMF cases showed one or more of these features required for diagnosis, by contrast with only 48% of ET patients. According to clinical data the cumulative risk of progression to advanced/overt PMF in pre-PMF was 36.9% after 15 years. After fitting cox regression models to analyze the impact of the minor criteria on overall survival, only leukocytosis remained as a significant predictor of survival in both pre-PMF and ET. Molecular characterization showed differences in survival in pre-PMF but not ET, with CALR being a more favorable mutation than JAK2. The different outcome of pre-PMF versus ET and associated molecular genetic data supports the concept of two different entities, rather than a continuum of the same disease. Although slightly less than 50% of ET patients also show one or more minor clinical criteria, accurate distinction between ET and pre-PMF is possible by following an integrated approach including histomorphological diagnosis and presence of minor clinical criteria.

HLA-C KIR-Ligands Determine the Impact of Anti-Thymocyte Globulin (ATG) on Graft versus Host and Graft versus Leukemia Effects Following Hematopoietic Stem Cell Transplantation

Rabbit anti-thymocyte globulins (ATGs) are widely used for the prevention of acute and chronic graft versus host disease (aGVHD, cGVHD) following allogeneic hematopoietic stem cell transplantation (HSCT). However, most prospective and retrospective studies did not reveal an overall survival (OS) benefit associated with ATG. Homozygosity for human leukocyte antigen (HLA)-C group 1 killer-cell immunoglobulin-like receptor ligands (KIR-L), i.e. C1/1 KIR-L status, was recently shown to be a risk factor for severe aGVHD. Congruously, we have previously reported favorable outcomes in C1/1 recipients after ATG-based transplants in a monocentric analysis. Here, within an extended cohort, we test the hypothesis that incorporation of ATG for GVHD prophylaxis may improve survival particularly in HSCT recipients with at least one C1 KIR-ligand. Retrospectively, 775 consecutive allogeneic (excluding haploidentical) HSCTs were analyzed, including peripheral blood and bone marrow grafts for adults with hematological diseases at two Austrian HSCT centers. ATG-Fresenius/Grafalon, Thymoglobuline, and alemtuzumab were applied in 256, 87, and 7 transplants, respectively (subsequently summarized as "ATG"), while 425 HSCT were performed without ATG. Median follow-up of surviving patients is 48 months. Adjusted for age, disease-risk, HLA-match, donor and graft type, sex match, cytomegalovirus serostatus, conditioning intensity, and type of post-grafting GVHD prophylaxis, Cox regression analysis of the entire cohort (n = 775) revealed a significant association of ATG with decreased non-relapse mortality (NRM) (risk ratio (RR), 0.57; p = 0.001), and overall mortality (RR, 0.71; p = 0.014). Upon stratification for HLA-C KIR-L, the greatest benefit for ATG emerged in C1/1 recipients (n = 291), by reduction of non-relapse (RR, 0.34; p = 0.0002) and overall mortality (RR, 0.50; p = 0.003). Less pronounced, ATG decreased NRM (RR, 0.60; p = 0.036) in HLA-C group 1/2 recipients (n = 364), without significantly influencing overall mortality (RR, 0.70; p = 0.065). After exclusion of higher-dose ATG-based transplants, serotherapy significantly improved both NRM (RR, 0.54; p = 0.019; n = 322) and overall mortality (RR, 0.60; p = 0.018) in C1/2 recipients as well. In both, C1/1 (RR, 1.70; p = 0.10) and particularly in C1/2 recipients (RR, 0.94; p = 0.81), there was no statistically significant impact of ATG on relapse incidence. By contrast, in C2/2 recipients (n = 121), ATG neither reduced NRM (RR, 1.10; p = 0.82) nor overall mortality (RR, 1.50; p = 0.17), but increased the risk for relapse (RR, 4.38; p = 0.02). These retrospective findings suggest ATG may provide a survival benefit in recipients with at least one C1 group KIR-L, by reducing NRM without significantly increasing the relapse risk.

Plerixafor as preemptive strategy results in high success rates in autologous stem cell mobilization failure

Plerixafor in combination with granulocyte-colony stimulating factor (G-CSF) is approved for autologous stem cell mobilization in poor mobilizing patients with multiple myeloma or malignant lymphoma. The purpose of this study was to evaluate efficacy and safety of plerixafor in an immediate rescue approach, administrated subsequently to G-CSF alone or chemotherapy and G-CSF in patients at risk for mobilization failure. Eighty-five patients mobilized with G-CSF alone or chemotherapy were included. Primary endpoint was the efficacy of the immediate rescue approach of plerixafor to achieve ≥2.0 × 10⁶ CD34⁺ cells/kg for a single or ≥5 × 10⁶ CD34⁺ cells/kg for a double transplantation and potential differences between G-CSF and chemotherapy-based mobilization. Secondary objectives included comparison of stem cell graft composition including CD34⁺ cell and lymphocyte subsets with regard to the mobilization regimen applied. No significant adverse events were recorded. A median 3.9-fold increase in CD34⁺ cells following plerixafor was observed, resulting in 97% patients achieving at least ≥2 × 10⁶ CD34+ cells/kg. Significantly more differentiated granulocyte and monocyte forming myeloid progenitors were collected after chemomobilization whereas more CD19⁺ and natural killer cells were collected after G-CSF. Fifty-two patients underwent transplantation showing rapid and durable engraftment, irrespectively of the stem cell mobilization regimen used. The addition of plerixafor in an immediate rescue model is efficient and safe after both, G-CSF and chemomobilization and results in extremely high success rates. Whether the differences in graft composition have a clinical impact on engraftment kinetics, immunologic recovery, and graft durability have to be analysed in larger prospective studies.

Iron metabolism and iron supplementation in cancer patients

Iron deficiency and iron deficiency-associated anemia are common complications in cancer patients. Most iron deficient cancer patients present with functional iron deficiency (FID), a status with adequate storage iron, but insufficient iron supply for erythroblasts and other iron dependent tissues. FID is the consequence of the cancer-associated cytokine release, while in absolute iron deficiency iron stores are depleted resulting in similar but often more severe symptoms of insufficient iron supply. Here we present a short review on the epidemiology, pathophysiology, diagnosis, clinical symptoms, and treatment of iron deficiency in cancer patients. Special emphasis is given to intravenous iron supplementation and on the benefits and limitations of different formulations. Based on these considerations and recommendations from current international guidelines we developed recommendations for clinical practice and classified the level of evidence and grade of recommendation according to the principles of evidence-based medicine.

Specific expression of OATPs in primary small cell lung cancer (SCLC) cells as novel biomarkers for diagnosis and therapy

The expression of organic anion transporting polypeptides (OATPs) was elucidated in cell lines from small cell lung cancer (SCLC) and lung carcinoids and in paraffin-embedded samples from primary and metastatic SCLCs. We found a strong relationship between OATP expression and the origin of the cells, as cells from primary or metastatic SCLC and carcinoid tumors differ with respect to OATP levels. OATP4A1 is most prominent in non-malignant lung tissue and in all SCLC and carcinoid cell lines and tissues, OATP5A1 is most prominent in metastatic cells, and OATP6A1 is most prominent in SCLC cell lines and tumors. Treatment with topotecan, etoposide and cisplatin caused significant changes in the expression patterns of OATP4A1, OATP5A1, OATP6A1, chromogranin and synaptophysin. This effect was also evident in GLC-14 cells from an untreated SCLC patient before chemotherapy compared to GLC-16/-19 chemoresistant tumor cells from this patient after therapy. mRNA expression of OATP4A1, 5A1 and 6A1 correlates with protein expression as confirmed by quantitative microscopic image analysis and Western blots. OATPs might be novel biomarkers for tumor progression and the development of metastasis in SCLC patients.

Decanucleotide insertion polymorphism of F7 significantly influences the risk of thrombosis in patients with essential thrombocythemia

OBJECTIVE

There is strong evidence that certain thrombophilic single nucleotide polymorphisms (SNPs) account for an increased risk of thrombosis. The additive impact of inherited thrombotic risk factors to a certain disease- immanent thrombotic risk is vastly unknown. Therefore, we aimed to investigate the influence of three novel, preselected SNPs on the risk of thrombosis in patients diagnosed with myeloproliferative neoplasm (MPN).

METHOD

In 167 patients with a diagnosis of essential thrombocythemia (ET) or prefibrotic primary myelofibrosis (PMF) thrombophilic SNPs in the genes of factor VII (F7), nitric oxide synthase 3 (NOS3) and FcɣRIIa (FCGR2A) were determined. Subsequently, the polymorphic variants were correlated with the incidence of major thrombosis after diagnosis.

RESULTS

Decanucleotide insertion polymorphism of F7 emerged as an independent, significant risk factor for total thrombosis and arterial thrombosis in particular in the whole group of patients (P = 0.0007) as well as in the separate analysis of patients with ET (P = 0.0002).

CONCLUSION

Our results illustrate that the risk of thrombosis in MPN is significantly multiplied by inherited thrombophilic SNPs. This result points to the importance of a combined consideration of the inherited and the acquired hypercoagulable state in patients with MPN. Larger studies are needed to confirm and extend these important findings.

The role of the organic anion transporting polypeptide OATP4A1 in immunactivation in colorectal cancer and inflammatory colon disease

481

Background: OATP-transporter proteins, such as OATP4A1, present influence cancer progression by providing compounds (hormones, prostaglandins, cyclic nucleotides, second messenger proteins, drugs) which either inhibit or stimulate tumor cells growth. Therefore, OATP expression in cancer cells and in the stroma, i.e., the microenvironment surrounding the epithelial cells can become a critical parameter. Methods: OATP4A1 was investigated in paraffin-embedded specimens from 148 patients with colorectal cancer and 20 with diverticulitis by immunohistochemistry (IHC) on an automatic quantitative microscopic image analysis system (TissuesFaxs). With the Histoquest program, the immunoreactive score (IRS), was calculated from the degree of the staining intensity and the number of OATP4A1-positive cells. To identify OATP4A1+-cells, double-immunofluorescence staining (IF) was done with antibodies against appropriate cellular markers. Results: OATP4A1 was located in the membrane and cytosol of colon cancer cells and immune cells, while membranous OATP4A1staining was seen in normal mucosa. OATP4A1 levels were higher in cancer cells in patients without tumor recurrence for up to 5 years (NR) than in patients with an early relapse (R) having IRS of 4391±231 and 3026±373 (Mean±SEM), respectively. Highest OATP4A1 levels were observed in immune cells in the tumors of Rs (IRS, 5712 ±254, while in NRs they were lower (IRS: 3549±358; p=0.05). In both groups, OATP4A1 levels in stroma cells were low (288±54 vs. 611±82). OATP4A1 expressing immune cell subtypes in cancer and diverticulitis sections were identified as CD45+ leukocytes, CD3+ T- and CD20+ B-cells, CD68+ macrophages, CD34+precursor cells. OATP4A1 was not detectable in Conclusions: High levels of OATP4A1 in immune cells in malignant and non-malignant colon disease suggest a role of the transporter in the activation of the immune system in malignant and non-malignant colon disease. Whether OATP4A1 might be a therapeutical target has to be established.

Duplex reverse-hybridization assay for the simultaneous detection of KRAS/BRAF mutations in FFPE-extracted genomic DNA from colorectal cancer specimens

We report the performance evaluation of a non-quantitative reverse-hybridization assay (KRAS-BRAF StripAssay) designed for the simultaneous detection of 10 mutations in codons 12 and 13 of the KRAS gene and BRAF mutation V600E. Dilution experiments using DNA from tumor cell lines or from formalin-fixed paraffin-embedded (FFPE) colorectal cancer (CRC) tissue were performed to assess assay sensitivity. Using 50 ng of total DNA (mutant and wild-type), the KRAS-BRAF StripAssay demonstrated a detection limit of 1% mutant sequence in a background of wild-type DNA. With respect to BRAF V600E, the KRAS-BRAF StripAssay was evaluated using 60 FFPE CRC samples previously analyzed by high resolution melting (HRM). Test strip hybridization identified 2/60 (3%) samples to carry the BRAF V600E mutation, and results were in agreement with those obtained by HRM analysis. This work demonstrates the KRAS-BRAF StripAssay to be a robust and sensitive method for the detection of common KRAS/BRAF mutations in genomic DNA isolated from FFPE tissue samples.

The prostaglandine E2 transporting organic anion transporting polypeptide OATP4A1: A potential prognostic marker in colorectal cancer?

430

Background: Organic anions transporters (OATPs) are important for tumor progression and therapeutic response by regulating cellular levels of hormones, second messenger proteins and drugs. OATP4A1 is a transporter of pro-inflammatory prostaglandin E2 and may contribute to cancer progression. Data on the expression of OATP4A1 and its clinical impact in primary colorectal cancer (CRC) is rare. Our study was designed to proof the overexpression of OATP4A1 in primary CRC. Methods: Frozen samples from 20 unselected CRC patients (pat) and five CRC cell lines were analyzed for OATP4A1 mRNA expression by real time PCR (mean level normalized to the calibrator, MNE). Immunohistochemistry was performed on paraffin- embedded tumor sections from 50 CRC pat., UICC 0-II (25/50 with subsequent relapse). An automatic quantitative image analysis program was applied to quantify OATP4A1 expression. Expression and intensity was correlated with clinical parameters and relapses. Results: Significant (p>0.05) higher levels of OATP4A1 mRNA were observed in 20 cancer samples as compared to adjacent non-cancerous tissue (2.44 vs. 0.46 MNE). The highest expression (9.85 MNE) was observed in a well-differentiated tumor sample. Similar high levels were observed in the COGA1A cell line, expression in the other cell lines ranged between 1.83 and 0.28 MNE. Immunoreactive staining for OATP4A1 was located in the membrane and occasionally in the cytosol of tumor cells, it was exclusively membrane located in the adjacent non-cancerous epithelial cells. The staining intensity was significantly higher in cancer cells compared to non-cancerous areas (1528±326 vs.376±218) while staining of stroma cells was only occasionally detectable. Surprisingly, the highest OATP4A1 levels were observed in immune cells (2839±381 vs.298±56). Data on the clinical impact of OATP4A1 in the early stage CRC pat. will be presented at the meeting. Conclusions: The profound expression of OATP4A1 in CRC cells and in the inflammatory infiltrates supports its implication on cancer progression. Suitability of OATP4A1 as a potential prognostic marker has to be established on a larger patient collective.

Impact of DNA mismatch repair deficiency on relapse rate in early-stage, sporadic colorectal cancer

415

Background: 15-20% of sporadic colorectal cancers (CRC) are characterized by DNA mismatch repair (MMR) deficiency resulting in the phenomenon of microsatellite instability (MSI). There is evidence that CRC with MSI have a significant better prognosis compared to those with intact MMR. We investigated MMR gene expression in patients (pat.) with CRC and correlated it with early relapse rate. Methods: The study relates to 146 pat. with primary CRC UICC stage 0-II who underwent surgical resection at the Donauspital in Vienna and had a complete follow up of at least 60 months. Expression of the MMR genes MLH1, PMS2, MSH2, MSH6 was detected by immunohistochemical staining. Expression of MMR genes was correlated with pat. and disease characteristics as well as relapse frequency within the first 5 years after diagnosis. Chi-squared test was used to compare the distribution of the given variables between MMR gene proficient and deficient pat. Results: Mean age of the total group was 66.14 years, 45.2% were females and 54.8 males. Localization of the tumor was the colon in 69.2% and the rectum in 30.8% of pat., respectively. 33.6% of diseases were classified as UICC stage 0-I, and 66.4% as UICC stage II. 37/ 146 pat. experienced relapse, mean duration to relapse was 2.17 years. 13.7% of all pat. displayed a MMR deficient state. All MMR deficiencies occurred in the colon, none in rectum tumors. MLH1 was always associated with PMS2 deficiency and occurred in 9.6% of pat. There was a significant difference in sex distribution between the proficient and deficient group with 71.4% females with MLH1/PMS2 deficiency (p= 0.038). MSH2 deficiency was detected in 1 pat. only. MSH6 deficiency occurred in 5.5% of pat., none of the variables was significantly different distributed between the proficient and deficient group. None of the MMR deficiencies correlated with relapse rate. Conclusions: Our data suggest that the supposed better prognosis of MMR deficient compared to proficient pat. might not be explained by a different relapse rate within 5 years from diagnosis. Larger and prospective trials are warranted to elucidate plausible explanations for the proposed survival benefit of a MMR deficient state.

Leukocytosis as an important risk factor for arterial thrombosis in WHO-defined early/prefibrotic myelofibrosis: an international study of 264 patients

We aimed to determine risk factors for thrombotic events in early/prefibrotic myelofibrosis diagnosed according to the World Health Organization criteria. Multivariate Cox regression analysis was calculated on a total number of 264 patients derived from an international database. After a median follow-up of 6.28 years, 42 (15.9%) patients experienced arterial (n = 31) or venous thrombosis (n = 11). A higher leukocyte count correlated with an increased risk for total thrombosis and in particular, with an increased risk for arterial thrombosis (P = 0.005, HR 1.15 and P = 0.047, HR 1.12, respectively). A platelet count above 870 × 10⁹/L was associated with a lower risk for total thrombosis and also for venous thrombosis (P = 0.022, HR 0.44 and P = 0.027, HR 0.19). Moreover, a lower hemoglobin level was associated with an increased risk for venous thrombosis (P = 0.007, HR 0.59). Our data indicate that leukocytosis is a prominent risk factor for thrombosis in early/prefibrotic MF.

Single center analysis of immunotherapy in mCRC patients

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Background: Immunotherapy in real-life, unselected patients with metastatic colorectal cancer (mCRC) was analyzed retrospectively at a single center in Austria. Methods: We have treated 137 mCRC patients with at least one antibody containing therapy since 2004 at our center based at data available at that time and patient eligibility. Results: Most mCRC patients were between 55 and 75 years old. The KRAS mutation testing performed routinely from 2008 onwards shows a distribution of 55 % wildtype (wt) and 45% mutant (mut) KRAS. Median overall survival (OS) was 24 months (n=82) with a trend towards greater benefit for KRAS wt patients compared to KRAS mut (26.8 vs. 20.9 months, respectively). Most patients received between 3 and 5 treatment lines. 40% of patients were treated with 5 therapies and 8% reached treatment line 8. The median OS correlated with the number of therapy lines. Chemotherapy alone regimens are decreasing constantly due to the establishment of biomarker analysis based treatment decisions and the increase in available antibodies for immunotherapy in mCRC. Based on direct positive experience with various antibodies, we were successfully treating patients repeatedly with the same antibodies in non-consecutive treatment lines. 75.7% of all patients treated with Cetuximab received the antibody only once during 3.8 therapy lines. 13% of patients who obtained the agent in two lines received on average 5.7 treatment lines resulting in improved OS. This was even more prominent in 8.5% patients receiving Cetuximab in 3 lines with a trend towards further OS benefit. These data describe that multiple applications of the same antibody is not only feasible but also very effective. Conclusions: By taping the full potential of treatment options, optimizing their usage and expanding the number of treatment lines we could achieve a median OS in real-life patients similar to that previously described in large phase III studies. Our analysis describes the following key factors for reproducing clinical benefits reported in large trials: biomarker assessment, early and if possible multiple applications of available therapeutic antibodies, treatment until progression and use of supportive therapy to alleviate possible toxicities.

Blood tests may predict early primary myelofibrosis in patients presenting with essential thrombocythemia

According to World Health Organization (WHO)-defined criteria, patients presenting clinically as essential thrombocythemia (ET) may show early primary myelofibrosis (PMF) with accompanying thrombocythemia [1]. Previous clinicopathological studies revealed that laboratory parameters like gender-matched hemoglobin (Hb), white blood cell (WBC) count, and particularly lactate dehydrogenase (LDH) values are significantly different in PMF [2]. By strictly applying the WHO criteria, our investigation was aimed to study sensitivity and specificity of these features in an exploratory cohort of 536 patients and to validate the results on an independently recruited series of 321 strictly corresponding patients. The discriminatory power of these parameters (Hb, WBC, and LDH) was tested by plotting their receiver operating characteristic curves. The best performance was found for LDH (areas under the curve, AUC 5 0.7059). WBC and Hb had superimposable curves, with AUC of 0.6279 and 0.6257, respectively. A diagnostic algorithm was generated by applying these parameters in a stepwise fashion. Nearly half of the patients could be correctly allocated to WHO-defined ET or early PMF in both cohorts investigated. It is important to note that this result does not substitute bone marrow morphology with hematological parameters, however, in clinical practice may alert physicians to get more suspicious of early PMF in a patient presumably presenting with ET.

Incidence and risk factors for bleeding in 1104 patients with essential thrombocythemia or prefibrotic myelofibrosis diagnosed according to the 2008 WHO criteria

In an international study of 1104 patients with essential thrombocythemia (ET), a histological review according to the 2008 World Health Organization (WHO) criteria confirmed ET in 891 patients (WHO-ET, 81%), and revised the diagnosis to prefibrotic primary myelofibrosis (PMF) in 180 patients (PMF, 16%). Major bleeding during follow-up occurred in 55 (6%) WHO-ET and 21 (12%) PMF patients (P = 0.009), at a rate of 0.79 and 1.39% patients per year, respectively, (P = 0.039). In a multivariable analysis, predictors of bleeding included diagnosis of PMF (P = 0.05; hazard ratio (HR) 1.74), leukocytosis (P = 0.04; HR 1.74), previous hemorrhage (P = 0.025; HR 2.35) and aspirin therapy (P=0.001; HR 3.16). The analysis restricted to patients with WHO-ET confirmed previous hemorrhage (P = 0.043; HR 1.92) and aspirin (P=0.027; HR 2.24) as independent risk factors. The current study reveals that major bleeding associated with thrombocytosis might be relatively specific to PMF, as opposed to WHO-defined ET. Furthermore, it shows that low-dose aspirin exacerbates these hemorrhagic events of PMF. In contrast, thrombocytosis per se was not a risk factor for bleeding; however, low-dose aspirin had a synergistic hemorrhagic effect unmasking the bleeding tendency of patients with extreme thrombocytosis. These observations carry significant therapeutic implications in these two WHO entities.

Survival and disease progression in essential thrombocythemia are significantly influenced by accurate morphologic diagnosis: an international study

PURPOSE

The WHO diagnostic criteria underscore the role of bone marrow (BM) morphology in distinguishing essential thrombocythemia (ET) from early/prefibrotic primary myelofibrosis (PMF). This study examined the clinical relevance of such a distinction.

METHODS

Representatives from seven international centers of excellence for myeloproliferative neoplasms convened to create a clinicopathologic database of patients previously diagnosed as having ET (N = 1,104). Study eligibility criteria included availability of treatment-naive BM specimens obtained within 1 year of diagnosis. All bone marrows subsequently underwent a central re-review.

RESULTS

Diagnosis was confirmed as ET in 891 patients (81%) and was revised to early/prefibrotic PMF in 180 (16%); 33 patients were not evaluable. In early/prefibrotic PMF compared with ET, the 10-year survival rates (76% and 89%, respectively) and 15-year survival rates (59% and 80%, respectively), leukemic transformation rates at 10 years (5.8% and 0.7%, respectively) and 15 years (11.7% and 2.1%, respectively), and rates of progression to overt myelofibrosis at 10 years (12.3% and 0.8%, respectively) and 15 years (16.9% and 9.3%) were significantly worse. The respective death, leukemia, and overt myelofibrosis incidence rates per 100 patient-years for early/prefibrotic PMF compared with ET were 2.7% and 1.3% (relative risk [RR], 2.1; P < .001), 0.6% and 0.1% (RR, 5.2; P = .001), and 1% and 0.5% (RR, 2.0; P = .04). Multivariable analysis confirmed these findings and also identified age older than 60 years (hazard ratio [HR], 6.7), leukocyte count greater than 11 × 10(9)/L (HR, 2.01), anemia (HR, 2.95), and thrombosis history (HR, 2.81) as additional risk factors for survival. Thrombosis and JAK2V617F incidence rates were similar between the two groups. Survival in ET was similar to the sex- and age-standardized European population.

CONCLUSION

This study validates the clinical relevance of strict adherence to WHO criteria in the diagnosis of ET and provides important information on survival, disease complication rates, and prognostic factors in strictly WHO-defined ET and early/prefibrotic PMF.

Organic Anion Transporting Polypeptide 5A1 (OATP5A1) in Small Cell Lung Cancer (SCLC) Cells: Possible Involvement in Chemoresistance to Satraplatin

BACKGROUND

The role of organic anion transporting polypeptide 5A1 (OATP5A1) a member of a family of drug transporters that mediate cellular uptake of drugs has not been characterized so far.

METHODS

Gene expression levels of OATP5A1 in small cell lung cancer (SCLC) cell lines were determined by real-time qPCR and chemosensitivity of HEK-293-SLCO5A1-transfected cells to satraplatin in MTT assays.

RESULTS

Significant expression of this transporter was found at the mRNA level, primarily in drug-resistant SCLC cells, and SLCO5A1-transfected HEK-293 cells showed higher resistance to satraplatin. OATP5A1 is found preferentially in cytoplasmic membranes of tumor cells, including SCLC.

CONCLUSIONS

OATP5A1 seems to effect intracellular transport of drugs and may participate in chemoresistance of SCLC by sequestration, rather than mediating cellular uptake. Since satraplatin failed to improve survival in SCLC patients, the relation of OATP5A1 expression to clinical drug resistance and its use as marker of chemoresistance should be further investigated.

Spontaneous changes in tumour cell dissemination to bone marrow in colorectal cancer

AIM

The study aimed to evaluate the incidence of disseminated tumour cells (DTCs) in bone marrow (BM) preoperatively and during follow up and to correlate these with established risk factors in patients with colorectal cancer.

METHOD

We prospectively studied BM in 57 patients using the anti-cytokeratin antibody A45-B/B3.

RESULTS

The overall detection rate of DTCs was 23% with a similar detection rate through all stages of the disease. No significant association was found between the presence of DTCs and clinicopathological parameters. After a median follow up of 35.4 months, no differences were found in relapse and overall survival between patients with and without DTC preoperatively. In 31 of 45 patients with local disease, we performed a follow-up BM examination after 1 year. In 26% of the patients, the BM status had changed as compared with the preoperative finding.

CONCLUSION

This is the first study to report the follow up of DTC in BM in colorectal cancer using the A45-B/B3 antibody. The presence of tumour cells in the preoperative BM had no impact on outcome. The BM status had changed after 12 months in a quarter of patients.

Circulating cytokeratin 18 fragments and activation of dormant tumor cells in bone marrow of cancer patients

In cancer patients detection of systemic disease is of great importance to obtain prognostic information and to guide therapy. Bone marrow (BM) seems to be a common homing tissue for the early spread of tumor cells from various epithelial tumors; however, verification of the prognostic significance of BM-disseminated tumor cells (BM-DTCs), is restricted to breast cancer so far. These cells may be dormant for a long time, and signals triggering their activation leading to recurrence remain to be characterized. A recent study involving metastatic breast cancer patients reported that the shortest disease-free survival is correlated with cytokeratin (CK)-negative BM aspirates and that CK-positive BM-DTCs correspond to dormant tumor cells. Soluble CK fragments in serum including CK18 and 19 (measured as TPS and CYFRA 21-1, respectively) and caspase-cleaved CK18 are widely used to monitor tumor progression and response to therapy, actually indicating proliferation and/or necrotic/apoptotic cell death. In order to assess the source of the CK fragments, we used determinations of CK18 and caspase-cleaved CK18 fragments in serum samples before and after radical tumor surgery in colon cancer patients. Elevated serum concentrations of CK18 were found to persist in patients with a high incidence of BM-DTCs, and high perioperative levels of caspase-cleaved CK18 fragments were detected in patients with early relapses, respectively. These results indicate that in some patients at increased risk of recurrence disseminated cell populations exist that are responsible for the release of the bulk of CK fragments after removal of the apparently nonmetastatic tumor. In good agreement with the results in metastatic breast cancer patients, release of CK18 or 19 fragments by BM-DTCs seem to indicate disseminated tumor cells mainly in a dormant state, whereas caspase-cleaved CK18 may indicate skipping of this latent phase and early progression. Therefore, caspase cleavage of CKs in intact tumor cells seems to accompany or is involved in the differentiation leading from dormant to progressively active disseminated tumor cells. Release of respective CK fragments would result in an apparent clearing of CK-positive cells in BM, leaving malignant cells that have possibly undergone an epithelial-mesenchymal transition. Micrometastatic cancer cell lines derived from breast cancer patients were found to display loss of epithelial CK8, 18 and 19 as well as ectopic expression of vimentin as in mesenchymal cells. In conclusion, degradation of CKs may represent a marker indicating reactivation of dormant tumor cells in BM.

Sensitive detection of KRAS mutations in archived formalin-fixed paraffin-embedded tissue using mutant-enriched PCR and reverse-hybridization

Recently, evidence has emerged indicating that assessment of KRAS mutations before anti-epidermal growth factor receptor therapy improves outcome in patients with metastatic colorectal cancer (CRC). We report here a novel reverse-hybridization (RH) assay to screen for KRAS mutations in formalin-fixed paraffin-embedded colorectal tissue samples. We combined mutant-enriched PCR based on peptide nucleic acid clamping and RH of amplification products to nitrocellulose test strips that contained a parallel array of oligonucleotide probes targeting 10 frequent mutations in codons 12 and 13 of the KRAS gene. DNA mixing experiments, which included eight different tumor cell lines with known KRAS mutations, were performed to examine the sensitivity of mutation detection. All KRAS mutations present in tumor cell lines were unambiguously identified by the RH assay with 1% of each cell line DNA diluted in normal DNA. RH was then used to screen for KRAS mutations in 74 colorectal tumor and 4 normal control samples. Twenty-six (35%) of the 74 tumor samples showed KRAS mutations. No mutation was found in the four samples of normal colorectal tissue. DNA sequencing without previous mutant enrichment, however, failed to detect four (15%) out of 26 KRAS-positive formalin-fixed paraffin-embedded samples (FFPE). This finding suggests that even after microdissection, mutant sequences in a given DNA isolate can be rare and more sensitive methods are needed for mutation analysis.