The prognostic impact of non-driver gene mutations and variant allele frequency in primary myelofibrosis

Prognostic impact of non-MPN driver gene mutations in primary myelofibrosis. MIPSS70: Mutation-Enhanced International Prognostic Score System.

Genomic classification and outcomes of young patients with polycythemia vera and essential thrombocythemia according to the presence of splanchnic vein thrombosis and its chronology

To elucidate the role of splanchnic vein thrombosis (SVT) and genomic characteristics in prognosis and survival, we compared patients with polycythemia vera (PV) or essential thrombocythemia (ET) presenting SVT at diagnosis (n = 69, median age 43 years) or during follow-up (n = 21, median age 46 years) to a sex- and age-matched control group of PV/ET without SVT (n = 165, median age 48 years). The majority of patients presenting with SVT at diagnosis were classified as myeloproliferative neoplasm with heterozygous JAK2 mutation (87% of cases vs. 69% in PV/ET control group, p < 0.05), characterized by low JAK2 allele burden and no high-risk mutations. Despite this lower molecular complexity, patients presenting with SVT showed a higher risk of death (HR 3.0, 95% CI 1.5-6.0, p = 0.003) and lower event-free survival (HR 3.0, 95% CI 1.9-4.8, p < 0.001) than age- and sex-matched PV/ET controls. In patients presenting with SVT, molecular high-risk was associated with increased risk of venous re-thrombosis (HR 5.8, 95% CI 1.4-24.0, p = 0.01). Patients developing SVT during follow-up were more frequently allocated in molecular high-risk than those with SVT at diagnosis (52% versus 13%, p < 0.05). In the whole cohort of patients, molecular classification identified PV/ET patients at higher risk of disease progression whereas DNMT3A/TET2/ASXL1 mutations were associated with higher risk of arterial thrombosis. In conclusion, clinical and molecular characteristics are different in PV/ET patients with SVT, depending on whether it occurs at diagnosis or at follow-up. Molecular characterization by NGS is useful for assessing the risk of thrombosis and disease progression in young patients with PV/ET.

Application of IPSET-thrombosis in 1366 Patients Prospectively Followed From the Spanish Registry of Essential Thrombocythemia

The International Prognostic Score of thrombosis in Essential Thrombocythemia (IPSET-thrombosis) and its revised version have been proposed to guide thrombosis prevention strategies. We evaluated both classifications to prognosticate thrombosis in 1366 contemporary essential thrombocythemia (ET) patients prospectively followed from the Spanish Registry of ET. The cumulative incidence of thrombosis at 10 years, taking death as a competing risk, was 11.4%. The risk of thrombosis was significantly higher in the high-risk IPSET-thrombosis and high-risk revised IPSET-thrombosis, but no differences were observed among the lower risk categories. Patients allocated in high-risk IPSET-thrombosis (subdistribution hazard ratios [SHR], 3.7 [95% confidence interval, CI, 1.6-8.7]) and high-risk revised IPSET-thrombosis (SHR, 3.2 [95% CI, 1.4-7.45]) showed an increased risk of arterial thrombosis, whereas both scoring systems failed to predict venous thrombosis. The incidence rate of thrombosis in intermediate risk revised IPSET-thrombosis (aged >60 years, JAK2-negative, and no history of thrombosis) was very low regardless of the treatment administered (0.9% and 0% per year with and without cytoreduction, respectively). Dynamic application of the revised IPSET-thrombosis showed a low rate of thrombosis when patients without history of prior thrombosis switched to a higher risk category after reaching 60 years of age. In conclusion, IPSET-thrombosis scores are useful for identifying patients at high risk of arterial thrombosis, whereas they fail to predict venous thrombosis. Controlled studies are needed to determine the appropriate treatment of ET patients assigned to the non-high-risk categories.

Clinical Characteristics and Outcomes of Patients with Primary and Secondary Myelofibrosis According to the Genomic Classification Using Targeted Next-Generation Sequencing

Myelofibrosis (MF) is a heterogeneous disease regarding its mutational landscape, clinical presentation, and outcomes. The aim of our work is to evaluate the genomic classification of MF considering whether it is primary or secondary. One-hundred seventy-five patients, 81 with primary MF (PMF) and 94 with secondary MF (SMF) were hierarchically allocated into eight molecular groups. We found that TP53 disruption/aneuploidy (n = 16, 9%) was more frequent (12% versus 6%) and showed higher allele burden (57% versus 15%, p = 0.01) in SMF than in PMF, and was associated with shorter survival (median 3.5 years). Mutations in chromatin/spliceosome genes (n = 72, 41%) represented the most frequent genomic group in PMF. Homozygous JAK2 mutation (n = 40, 23%) was enriched with old patients with SMF after long-standing polycythemia vera, whereas MF with heterozygous JAK2 mutation (n = 22, 13%) was similarly distributed among PMF and SMF. MF with CALR mutation (n = 19, 11%) predominated in post-essential thrombocythemia MF. The remaining genomic groups were infrequent. TP53 disruption, chromatin/spliceosome mutation, and homozygous JAK2 mutation were associated with significantly shorter survival and higher risk of progression. In conclusion, genomic classification reveals different pathogenic pathways between PMF and SMF and provides relevant information regarding disease phenotype and outcomes.

Final Study Report of Andexanet Alfa for Major Bleeding With Factor Xa Inhibitors

BACKGROUND

Andexanet alfa is a modified recombinant inactive factor Xa (FXa) designed to reverse FXa inhibitors. ANNEXA-4 (Andexanet Alfa, a Novel Antidote to the Anticoagulation Effects of Factor Xa Inhibitors) was a multicenter, prospective, phase-3b/4, single-group cohort study that evaluated andexanet alfa in patients with acute major bleeding. The results of the final analyses are presented.

METHODS

Patients with acute major bleeding within 18 hours of FXa inhibitor administration were enrolled. Co-primary end points were anti-FXa activity change from baseline during andexanet alfa treatment and excellent or good hemostatic efficacy, defined by a scale used in previous reversal studies, at 12 hours. The efficacy population included patients with baseline anti-FXa activity levels above predefined thresholds (≥75 ng/mL for apixaban and rivaroxaban, ≥40 ng/mL for edoxaban, and ≥0.25 IU/mL for enoxaparin; reported in the same units used for calibrators) who were adjudicated as meeting major bleeding criteria (modified International Society of Thrombosis and Haemostasis definition). The safety population included all patients. Major bleeding criteria, hemostatic efficacy, thrombotic events (stratified by occurring before or after restart of either prophylactic [ie, a lower dose, for prevention rather than treatment] or full-dose oral anticoagulation), and deaths were assessed by an independent adjudication committee. Median endogenous thrombin potential at baseline and across the follow-up period was a secondary outcome.

RESULTS

There were 479 patients enrolled (mean age, 78 years; 54% male, 86% White; 81% anticoagulated for atrial fibrillation at a median time of 11.4 hours since last dose, with 245 (51%) on apixaban, 176 (37%) on rivaroxaban, 36 (8%) on edoxaban, and 22 (5%) on enoxaparin. Bleeding was predominantly intracranial (n=331 [69%]) or gastrointestinal (n=109 [23%]). In evaluable apixaban patients (n=172), median anti-FXa activity decreased from 146.9 ng/mL to 10.0 ng/mL (reduction, 93% [95% CI, 94-93]); in rivaroxaban patients (n=132), it decreased from 214.6 ng/mL to 10.8 ng/mL (94% [95% CI, 95-93]); in edoxaban patients (n=28), it decreased from 121.1 ng/mL to 24.4 ng/mL (71% [95% CI, 82-65); and in enoxaparin patients (n=17), it decreased from 0.48 IU/mL to 0.11 IU/mL (75% [95% CI, 79-67]). Excellent or good hemostasis occurred in 274 of 342 evaluable patients (80% [95% CI, 75-84]). In the safety population, thrombotic events occurred in 50 patients (10%); in 16 patients, this occurred during treatment with prophylactic anticoagulation that began after the bleeding event. No thrombotic episodes occurred after oral anticoagulation restart. Specific to certain populations, reduction of anti-FXa activity from baseline to nadir significantly predicted hemostatic efficacy in patients with intracranial hemorrhage (area under the receiver operating characteristic curve, 0.62 [95% CI, 0.54-0.70]) and correlated with lower mortality in patients <75 years of age (adjusted P=0.022; unadjusted P=0.003). Median endogenous thrombin potential was within the normal range by the end of andexanet alfa bolus through 24 hours for all FXa inhibitors.

CONCLUSIONS

In patients with major bleeding associated with the use of FXa inhibitors, treatment with andexanet alfa reduced anti-FXa activity and was associated with good or excellent hemostatic efficacy in 80% of patients.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02329327.

Predictors of thrombosis and bleeding in 1613 myelofibrosis patients from the Spanish Registry of Myelofibrosis

Available data have proved insufficient to develop consensus recommendations on the prevention of thrombosis and bleeding in myelofibrosis (MF). We evaluated the incidence and risk factors of vascular complications in 1613 patients from the Spanish Myelofibrosis Registry. Over a total of 6981 patient-years at risk, 6.4% of the study population had at least one thrombotic event after MF diagnosis, amounting to an incidence rate of 1.65 per 100 patient-years. Prior history of thrombosis, the JAK2 mutation, and the intermediate-2/high-risk International Prognostic Scoring System (IPSS) categories conferred an increased thrombotic risk after adjustment for the risk-modifying effect of anti-thrombotic and cytoreductive treatments. History of thrombosis and the JAK2 mutation allowed us to pinpoint a group of patients at higher risk of early thrombosis. No decreased incidence of thrombosis was observed while patients were on anti-thrombotic or cytoreductive treatment. An increased risk of venous thrombosis was found during treatment with immunomodulatory agents. A total of 5.3% of patients had at least one episode of major bleeding, resulting in an incidence rate of 1.5 events per 100 patient-years. Patients in the intermediate-2/high-risk IPSS categories treated with anti-coagulants had an almost sevenfold increased risk of major bleeding. These findings should prove useful for guiding decision-making in clinical practice.

Real-world analysis of main clinical outcomes in patients with polycythemia vera treated with ruxolitinib or best available therapy after developing resistance/intolerance to hydroxyurea

Background

Ruxolitinib is approved for patients with polycythemia vera (PV) who are resistant/intolerant to hydroxyurea, but its impact on preventing thrombosis or disease‐progression is unknown.

Methods

A retrospective, real‐world analysis was performed on the outcomes of 377 patients with resistance/intolerance to hydroxyurea from the Spanish Registry of Polycythemia Vera according to subsequent treatment with ruxolitinib (n = 105) or the best available therapy (BAT; n = 272). Survival probabilities and rates of thrombosis, hemorrhage, acute myeloid leukemia, myelofibrosis, and second primary cancers were calculated according to treatment. To minimize biases in treatment allocation, all results were adjusted by a propensity score for receiving ruxolitinib or BAT.

Results

Patients receiving ruxolitinib had a significantly lower rate of arterial thrombosis than those on BAT (0.4% vs 2.3% per year; P = .03), and this persisted as a trend after adjustment for the propensity to have received the drug (incidence rate ratio, 0.18; 95% confidence interval, 0.02‐1.3; P = .09). There were no significant differences in the rates of venous thrombosis (0.8% and 1.1% for ruxolitinib and BAT, respectively; P = .7) and major bleeding (0.8% and 0.9%, respectively; P = .9). Ruxolitinib exposure was not associated with a higher rate of second primary cancers, including all types of neoplasia, noncutaneous cancers, and nonmelanoma skin cancers. After a median follow‐up of 3.5 years, there were no differences in survival or progression to acute leukemia or myelofibrosis between the 2 groups.

Conclusions

The results suggest that ruxolitinib treatment for PV patients with resistance/intolerance to hydroxyurea may reduce the incidence of arterial thrombosis.

Lay Summary

Ruxolitinib is better than other available therapies in achieving hematocrit control and symptom relief in patients with polycythemia vera who are resistant/intolerant to hydroxyurea, but we still do not know whether ruxolitinib provides an additional benefit in preventing thrombosis or disease progression.

We retrospectively studied the outcomes of 377 patients with resistance/intolerance to hydroxyurea from the Spanish Registry of Polycythemia Vera according to whether they subsequently received ruxolitinib (n = 105) or the best available therapy (n = 272).

Our findings suggest that ruxolitinib could reduce the incidence of arterial thrombosis, but a disease‐modifying effect could not be demonstrated for ruxolitinib in this patient population.

Ruxolitinib may reduce the incidence of arterial thrombosis in patients with polycythemia vera resistant/intolerant to hydroxyurea.

Patients' perceptions with dabigatran in patients with atrial fibrillation previously treated with vitamin K antagonists

Aim: To analyze the perception of anticoagulation with dabigatran in patients with nonvalvular atrial fibrillation previously treated with vitamin K antagonists over a 6-month period. Materials & methods: This is a prospective, noninterventional, noncontrolled, multicenter study. To assess patients' perceptions, PACT-Q2 questionnaire was completed. Results: Six hundred and fifty nine patients (73.1 ± 9.4 years, CHA₂DS₂-VASc 3.6 ± 1.6) were included. At baseline, the convenience and satisfaction scores were 60.9 ± 24.9 and 49.9 ± 17.7, respectively. The scores significantly increased along the study. Convenience score was higher in males and in patients with low-moderate thromboembolic risk. Satisfaction score was higher in females. Only 8.0% of patients discontinued dabigatran (3.7% due to side effects). Conclusion: Convenience and satisfaction scores for nonvalvular atrial fibrillation patients treated with dabigatran at 6 months were significantly better than with previous vitamin K antagonists.

Natural history of polycythemia vera and essential thrombocythemia presenting with splanchnic vein thrombosis

Patients with polycythemia vera (PV) or essential thrombocythemia (ET) presenting with splanchnic vein thrombosis (SVT) might have a specific clinico-biological profile. To investigate this hypothesis, 3705 PV/ET patients from three national registers, 118 of them presenting with SVT, were reviewed. After correction for age and sex, PV/ET patients with SVT showed an increased risk of death (HR 2.47, 95% CI 1.5-4.01, p < 0.001), venous thrombosis (IRR 3.4, 95%CI 2.1-5.5, p < 0.001), major bleeding (IRR 3.6, 95%CI 2.3-5.5, p < 0.001), and second cancer (IRR 2.37, 95%CI 1.4-4.1, p = 0.002). No case of acute leukemia was documented among patients with PV/ET presenting with SVT and seven of them (6%) progressed to myelofibrosis. SVT was not associated with lower risk of MF after correction by age and sex. Patients with SVT more frequently died from complications related to hepatic disease, major bleeding, or second cancer, resulting in a 5-year reduction of age- and sex-adjusted median survival. In conclusion, PV and ET patients presenting with SVT have shorter survival than patients with PV and ET of the same age and sex. This excess mortality is related to liver disease, major bleeding, and second cancer rather than to the natural evolution of the MPN.

Idarucizumab, but not procoagulant concentrates, fully restores dabigatran-altered platelet and fibrin components of hemostasis

BACKGROUND

Comparative studies on the restoration of hemostasis with different reversal agents after dabigatran therapy have not been performed. We compared the efficacy and prothrombotic potential of the specific antidote idarucizumab with that of previously recommended non-specific procoagulant concentrates.

STUDY DESIGN AND METHODS

We explored the in vitro effects of dabigatran (184 ng/mL) on fibrin and platelet-aggregate formation onto a damaged vessel under flow conditions (600 s^-1 ). The reversal mechanisms and efficacy of idarucizumab (0.3-3 mg/mL) were compared with that of the non-specific procoagulant concentrates aPCC (25-75 U/Kg), PCC (70 U/Kg), or rFVIIa (120 μg/Kg). Generation of thrombin and prothrombin fragment (F1 + 2), and thromboelastometry parameters of clot formation were measured.

RESULTS

Dabigatran caused pronounced reductions in fibrin (87%) and platelet interactions (36%) with damaged vessels (p < 0.01) and significantly impaired thrombin generation and thromboelastometric parameters (delayed dynamics and reduced firmness). Idarucizumab completely normalized rates of fibrin and platelet coverage to baseline values in flow studies; and reversed the alterations in thrombin generation, F1 + 2 and thromboelastometry parameters produced by dabigatran. In comparison, aPCC and PCC only partially compensated for the dabigatran-induced alterations in fibrin deposition, but were unable to fully restore them to baseline values. Reversal with aPCC or PCC improved the majority of alterations in coagulation-related tests, but tended to overcompensate thrombin generation kinetics and significantly increased F1 + 2 levels.

CONCLUSION

Idarucizumab antagonizes alterations of direct and indirect biomarkers of hemostasis caused by dabigatran. In our studies, idarucizumab was clearly more efficacious than strategies with non-specific procoagulant concentrates and devoid of the excessive procoagulant tendency observed with the latter.

Essential thrombocythaemia with mutation in MPL: clinicopathological correlation and comparison with JAK2V617F-mutated and CALR-mutated genotypes

AIM

To characterise the clinical and histological features of MPL-mutated essential thrombocythaemia (ET).

PATIENTS AND METHODS

Bone marrow biopsies of 175 patients with ET were centrally reviewed according to the 2016 WHO classification, including 42 cases with MPL mutation, 98 JAK2V617F-mutated and 35 CALR-mutated. Clinical and histological features were compared among the three genotypes included in the current 2016 WHO classification and among the different types of MPL mutations.

RESULTS

Patients with MPL-mutated ET were significantly older than those with the other genotypes. Haematological values at diagnosis were similar among MPL-mutated and CALR-mutated ET, with both genotypes showing higher platelet counts and lower haemoglobin values than ET with JAK2V617F genotype. In the bone marrow, the median number of megakaryocytes was higher in MPL and CALR than in JAK2V617F genotype (16, 19 and 14 megakaryocytes per ×20 power field, respectively, p=0.004). Histological features of prefibrotic myelofibrosis were rarely observed in MPL genotype, whereas sinusoidal hyperplasia, dense clusters of megakaryocytes and reticulin fibrosis were more frequent in CALR-mutated ET, with 11% of such cases fulfilling WHO 2016 histological criteria of prefibrotic myelofibrosis. With a median follow-up of 3.5 years, no significant differences were seen among genotypes regarding survival, vascular complications or myelofibrotic transformation. There were no significant differences in the clinical data or in the histological characteristics depending on the type of MPL mutation.

CONCLUSION

MPL and CALR ET genotypes share clinical and histological characteristics. In contrast to CALR genotype, features of prefibrotic myelofibrosis are uncommon in MPL-mutated ET.

Benefit-risk profile of cytoreductive drugs along with antiplatelet and antithrombotic therapy after transient ischemic attack or ischemic stroke in myeloproliferative neoplasms

We analyzed 597 patients with myeloproliferative neoplasms (MPN) who presented transient ischemic attacks (TIA, n = 270) or ischemic stroke (IS, n = 327). Treatment included aspirin, oral anticoagulants, and cytoreductive drugs. The composite incidence of recurrent TIA and IS, acute myocardial infarction (AMI), and cardiovascular (CV) death was 4.21 and 19.2%, respectively at one and five years after the index event, an estimate unexpectedly lower than reported in the general population. Patients tended to replicate the first clinical manifestation (hazard ratio, HR: 2.41 and 4.41 for recurrent TIA and IS, respectively); additional factors for recurrent TIA were previous TIA (HR: 3.40) and microvascular disturbances (HR: 2.30); for recurrent IS arterial hypertension (HR: 4.24) and IS occurrence after MPN diagnosis (HR: 4.47). CV mortality was predicted by age over 60 years (HR: 3.98), an index IS (HR: 3.61), and the occurrence of index events after MPN diagnosis (HR: 2.62). Cytoreductive therapy was a strong protective factor (HR: 0.24). The rate of major bleeding was similar to the general population (0.90 per 100 patient-years). In conclusion, the long-term clinical outcome after TIA and IS in MPN appears even more favorable than in the general population, suggesting an advantageous benefit-risk profile of antithrombotic and cytoreductive treatment.

Betrixaban: a direct oral inhibitor of activated factor X for the prophylaxis of venous thromboembolism in patients hospitalized for acute medical illness

Venous thromboembolism (VTE), comprising deep vein thrombosis and pulmonary embolism, is a serious clinical and public health concern. Hospitalization is a major risk factor for developing VTE. Hospital-associated events account for more than 50% of all cases of VTE. Heparins have demonstrated to be efficacious in the prevention of VTE in medically ill patients. Despite the demonstrated efficacy and safety of the available direct oral anticoagulants in the prevention and treatment of different thromboembolic conditions, their net benefit in the prevention of VTE in hospitalized medically ill patients has not been fully confirmed. Betrixaban is an oral, specific and direct inhibitor of human coagulation factor Xa with demonstrated efficacy and safety for the prevention of VTE in patients undergoing total knee replacement and in patients with nonvalvular atrial fibrillation. Recent studies have successfully evaluated betrixaban 80 mg once daily in the prevention of VTE in acute medically ill patients in a large phase III trial. This review will address preclinical pharmacology and main aspects of the clinical development of betrixaban as an antithrombotic agent, with specific attention to recent studies on the prophylaxis of VTE in a specific population of patients hospitalized for acute medical illnesses.

Andexanet alfa: a recombinant mimetic of human factor Xa for the reversal of anticoagulant therapies

Activated coagulation factor X (FXa) is a common target for classic and newer anticoagulants. Parenteral anticoagulants with an indirect inhibitory action on FXa (low-molecular-weight heparins) have a well-established clinical efficacy in the prophylaxis and therapy of thromboembolic conditions. More recently developed direct oral anticoagulants (DOACs) have emerged as a new class of antithrombotic drugs. Rivaroxaban, apixaban and edoxaban are direct inhibitors of FXa approved for the management of venous thromboembolism and stroke prevention in atrial fibrillation. Although these DOACs are associated with fewer hemorrhagic side effects than classic vitamin K antagonists, bleeding is still a main complication. FXa antagonists had no specific agents that could reverse their antihemostatic effects. Andexanet alfa is a modified, recombinant human FXa molecule with an enhanced ability to bind to both direct and indirect FXa inhibitors, but unable to contribute to blood coagulation mechanisms. Andexanet alfa is designed to reverse the anticoagulant effects of FXa inhibitors. This review will address the preclinical pharmacology and the main aspects of the clinical development of andexanet alfa for the reversal of anticoagulant therapies with an inhibitory action on FXa. It will also summarize additional completed or ongoing studies on andexanet alfa available to the scientific community until present.

Differential inhibitory action of apixaban on platelet and fibrin components of forming thrombi: Studies with circulating blood and in a platelet-based model of thrombin generation

Introduction

Mechanisms of action of direct oral anticoagulants (DOAC) suggest a potential therapeutic use in the prevention of thrombotic complications in arterial territories. However, effects of DOACs on platelet activation and aggregation have not been explored in detail. We have investigated the effects of apixaban on platelet and fibrin components of thrombus formation under static and flow conditions.

Methods

We assessed the effects of apixaban (10, 40 and 160 ng/mL) on: 1) platelet deposition and fibrin formation onto a thrombogenic surface, with blood circulating at arterial shear-rates; 2) viscoelastic properties of forming clots, and 3) thrombin generation in a cell-model of coagulation primed by platelets.

Results

In studies with flowing blood, only the highest concentration of apixaban, equivalent to the therapeutic C_max, was capable to significantly reduce thrombus formation, fibrin association and platelet-aggregate formation. Apixaban significantly prolonged thromboelastometry parameters, but did not affect clot firmness. Interestingly, results in a platelet-based model of thrombin generation under more static conditions, revealed a dose dependent persistent inhibitory action by apixaban, with concentrations 4 to 16 times below the therapeutic C_max significantly prolonging kinetic parameters and reducing the total amount of thrombin generated.

Conclusions

Our studies demonstrate the critical impact of rheological conditions on the antithrombotic effects of apixaban. Studies under flow conditions combined with modified thrombin generation assays could help discriminating concentrations of apixaban that prevent excessive platelet accumulation, from those that deeply impair fibrin formation and may unnecessarily compromise hemostasis.

Antiplatelet therapy versus observation in low-risk essential thrombocythemia with a CALR mutation

The role of antiplatelet therapy as primary prophylaxis of thrombosis in low-risk essential thrombocythemia has not been studied in randomized clinical trials. We assessed the benefit/risk of low-dose aspirin in 433 patients with low-risk essential thrombocythemia (271 with a CALR mutation, 162 with a JAK2(V617F) mutation) who were on antiplatelet therapy or observation only. After a follow up of 2215 person-years free from cytoreduction, 25 thrombotic and 17 bleeding episodes were recorded. In CALR-mutated patients, antiplatelet therapy did not affect the risk of thrombosis but was associated with a higher incidence of bleeding (12.9 versus 1.8 episodes per 1000 patient-years, P=0.03). In JAK2(V617F)-mutated patients, low-dose aspirin was associated with a reduced incidence of venous thrombosis with no effect on the risk of bleeding. Coexistence of JAK2(V617F)-mutation and cardiovascular risk factors increased the risk of thrombosis, even after adjusting for treatment with low-dose aspirin (incidence rate ratio: 9.8; 95% confidence interval: 2.3-42.3; P=0.02). Time free from cytoreduction was significantly shorter in CALR-mutated patients with essential thrombocythemia than in JAK2(V617F)-mutated ones (median time 5 years and 9.8 years, respectively; P=0.0002) and cytoreduction was usually necessary to control extreme thrombocytosis. In conclusion, in patients with low-risk, CALR-mutated essential thrombocythemia, low-dose aspirin does not reduce the risk of thrombosis and may increase the risk of bleeding.

Dosing of rivaroxaban by indication: getting the right dose for the patient

INTRODUCTION

Vitamin K antagonists were the only oral anticoagulants available for several decades, but they require frequent coagulation monitoring and dose adjustment. The direct oral anticoagulants rivaroxaban , dabigatran, apixaban, and, most recently, edoxaban have been approved for the management of specific thromboembolic indications.

AREAS COVERED

This review will provide a brief overview of the cell-based coagulation model, the main determinants of arterial and venous thrombosis, and the pharmacological rationale and clinical evidence for the different dosing regimens of rivaroxaban. Published articles indexed on PubMed and Medline covering arterial and venous thrombi pathophysiology, pharmacokinetics, and pharmacodynamics of rivaroxaban, and Phase II and Phase III clinical studies with rivaroxaban as well as real-world evidence were analyzed.

EXPERT OPINION

Education on pharmacokinetic/pharmacodynamic characteristics, as well as how to manage adverse events, is needed to increase physician knowledge and confidence in using direct oral anticoagulants, as specifically discussed for rivaroxaban in this article. The continued uptake of direct oral anticoagulants in clinical practice depends on understanding of the clinical evidence and reassurance provided by emerging real-world data.

Oral anticoagulation to prevent thrombosis recurrence in polycythemia vera and essential thrombocythemia

It is unclear whether anticoagulation guidelines intended for the general population are applicable to patients with polycythemia vera (PV) and essential thrombocythemia (ET). In the present study, the risk of thrombotic recurrence was analyzed in 150 patients with PV and ET treated with vitamin K antagonists (VKA) because of an arterial or venous thrombosis. After an observation period of 963 patient-years, the incidence of re-thrombosis was 4.5 and 12 per 100 patient-years under VKA therapy and after stopping it, respectively (P < 0.0005). After a multivariate adjustment for other prognostic factors, VKA treatment was associated with a 2.8-fold reduction in the risk of thrombotic recurrence. Notably, VKA therapy offset the increased risk of re-thrombosis associated with a prior history of remote thrombosis. Both the protective effect of VKA therapy and the predisposing factors for recurrence were independent of the anatomical site involved in the index thrombosis. Treatment periods with VKA did not result in a higher incidence of major bleeding as compared with those without VKA. These findings support the use of long-term anticoagulation for the secondary prevention of thrombosis in patients with PV and ET, particularly in those with history of remote thrombosis.

Cerebral vein thrombosis in patients with Philadelphia-negative myeloproliferative neoplasms. An European Leukemia Net study

To investigate the characteristics and clinical course of cerebral vein thrombosis (CVT) in patients with myeloproliferative neoplasms (MPN) we compared 48 patients with MPN and CVT (group MPN-CVT) to 87 with MPN and other venous thrombosis (group MPN-VT) and 178 with MPN and no thrombosis (group MPN-NoT) matched by sex, age at diagnosis of MPN (±5 years) and type of MPN. The study population was identified among 5,500 patients with MPN, from January 1982 to June 2013. Thrombophilia abnormalities were significantly more prevalent in the MPN-CVT and MPN-VT than in MPN-NoT group (P = 0.015), as well as the JAK2 V617F mutation in patients with essential thrombocythemia (P = 0.059). Compared to MPN-VT, MPN-CVT patients had a higher rate of recurrent thrombosis (42% vs. 25%, P = 0.049) despite a shorter median follow-up period (6.1 vs. 10.3 years, P = 0.019), a higher long-term antithrombotic (94% vs. 84%, P = 0.099) and a similar cytoreductive treatment (79% vs. 70%, P = 0.311). The incidence of recurrent thrombosis was double in MPN-CVT than in MPN-VT group (8.8% and 4.2% patient-years, P = 0.022), and CVT and unprovoked event were the only predictive variables in a multivariate model including also sex, blood count, thrombophilia, cytoreductive, and antithrombotic treatment (HR 1.97, 95%CI 1.05-3.72 and 2.09, 1.09-4.00, respectively).

The pharmacokinetics of edoxaban for the prevention and treatment of venous thromboembolism

INTRODUCTION

Thromboembolic diseases will become the most important contributors to mortality and morbidity for modern societies. Current antithrombotic strategies using heparins or vitamin K antagonists are inconvenient, with limitations and inherent side effects. A series of new oral anticoagulants with powerful and reliable antithrombotic actions have been developed in the last decade.

AREAS COVERED

Edoxaban is a direct and specific inhibitor of activated factor X, delivered orally. This article reviews literature from PubMed and articles referenced within. The text explores the pharmacological aspects of its antithrombotic action. Pharmacokinetics, metabolism and drug interactions are examined. The review places the results of recent clinical trials that have evaluated the antithrombotic potential of edoxaban versus standard antithrombotic therapies in the prophylaxis and treatment of venous thromboembolism into perspective. The possible relationship between the pharmacokinetic profile of edoxaban and the favorable results in clinical trials is discussed.

EXPERT OPINION

Edoxaban is perceived as a major advance, compared to vitamin K antagonists, in the prevention and treatment of thromboembolic disease given its favorable efficacy, safety, pharmacokinetic profile and renal clearance. The results of ongoing large international trials exploring the prevention of thrombotic complications in patients in different clinical settings should ensure the approval of edoxaban to treat new indications.

Reversal of apixaban induced alterations in hemostasis by different coagulation factor concentrates: significance of studies in vitro with circulating human blood

Apixaban is a new oral anticoagulant with a specific inhibitory action on FXa. No information is available on the reversal of the antihemostatic action of apixaban in experimental or clinical settings. We have evaluated the effectiveness of different factor concentrates at reversing modifications of hemostatic mechanisms induced by moderately elevated concentrations of apixaban (200 ng/ml) added in vitro to blood from healthy donors (n = 10). Effects on thrombin generation (TG) and thromboelastometry (TEM) parameters were assessed. Modifications in platelet adhesive, aggregating and procoagulant activities were evaluated in studies with blood circulating through damaged vascular surfaces, at a shear rate of 600 s(-1). The potential of prothrombin complex concentrates (PCCs; 50 IU/kg), activated prothrombin complex concentrates (aPCCs; 75 IU/kg), or activated recombinant factor VII (rFVIIa; 270 μg/kg), at reversing the antihemostatic actions of apixaban, were investigated. Apixaban interfered with TG kinetics. Delayed lag phase, prolonged time to peak and reduced peak values, were improved by the different concentrates, though modifications in TG patterns were diversely affected depending on the activating reagents. Apixaban significantly prolonged clotting times (CTs) in TEM studies. Prolongations in CTs were corrected by the different concentrates with variable efficacies (rFVIIa≥aPCC>PCC). Apixaban significantly reduced fibrin and platelet interactions with damaged vascular surfaces in perfusion studies (p<0.05 and p<0.01, respectively). Impairments in fibrin formation were normalized by the different concentrates. Only rFVIIa significantly restored levels of platelet deposition. Alterations in hemostasis induced by apixaban were variably compensated by the different factor concentrates investigated. However, effects of these concentrates were not homogeneous in all the tests, with PCCs showing more efficacy in TG, and rFVIIa being more effective on TEM and perfusion studies. Our results indicate that rFVIIa, PCCs and aPCCs have the potential to restore platelet and fibrin components of the hemostasis previously altered by apixaban.

Cytoreduction plus low-dose aspirin versus cytoreduction alone as primary prophylaxis of thrombosis in patients with high-risk essential thrombocythaemia: an observational study

The effectiveness of low-dose aspirin in the primary prevention of thrombosis in patients with high-risk essential thrombocythaemia (ET) treated with cytoreductive drugs is not well established. The risk-benefit balance of low-dose aspirin plus cytoreductive therapy compared with cytoreduction alone was retrospectively analysed in 247 patients with high-risk ET without prior thrombosis. Follow-up was 763 and 685 person-years for cytoreduction plus low-dose aspirin and cytoreduction alone, respectively. The rate of thrombosis was not significantly reduced in patients on cytoreduction plus aspirin (14·4 events per 1000 person-years) when compared with those on cytoreduction alone (24·8 events per 1000 person-years; P = 0·2). However, in the subgroup of patients older than 60 years, the addition of low-dose aspirin was associated with a significantly lower rate of thrombosis (8·6 vs. 29·2 thrombosis per 1000 person-years for combined treatment and cytoreduction alone, respectively, P = 0·02). The rate of major bleeding was significantly higher with combined therapy than with cytoreduction alone both in the whole series (14·4 vs. 1·4 haemorrhagic events per 1000 person-years, respectively, P = 0·006) and in the subgroup of patients older than 60 years. In conclusion, low-dose aspirin benefits high-risk ET patients older than 60 years receiving cytoreductive therapy as primary prophylaxis of thrombosis.

Assessment and prognostic value of the European LeukemiaNet criteria for clinicohematologic response, resistance, and intolerance to hydroxyurea in polycythemia vera

Criteria of response and definition of resistance and intolerance to hydroxyurea (HU) in polycythemia vera (PV) were proposed by the European LeukemiaNet (ELN). Such criteria were evaluated in 261 PV patients (median follow-up, 7.2 years) treated with HU for a median of 4.4 years. Complete response, partial response, and no response were observed in 24%, 66%, and 10% of patients, respectively. Achieving ELN response (complete or partial) or hematocrit response did not result in better survival or less thrombosis and bleeding. On the contrary, having no response in leukocyte count was associated with higher risk of death (HR, 2.7; 95% confidence interval [CI], 1.3%-5.4%; P = .007), whereas lack of response in platelet count involved a higher risk of thrombosis and bleeding. Resistance and intolerance to HU was registered in 11% and 13% of patients, respectively. Resistance to HU was associated with higher risk of death (HR, 5.6; 95% CI, 2.7%-11.9%; P < .001) and transformation (HR, 6.8; 95% CI, 3.0%-15.4%; P < .001). In summary, fulfilling the ELN definition for response to HU was not associated with a benefit in the clinical outcome in PV, whereas response in platelet and white blood cell counts were predictive of less thrombohemorrhagic complications and better prognosis, respectively. Resistance to HU was an adverse prognostic factor.

Efficacy and tolerability of hydroxyurea in the treatment of the hyperproliferative manifestations of myelofibrosis: results in 40 patients

Hydroxyurea (HU) is frequently given as treatment for myelofibrosis (MF), but data on its efficacy and tolerability are scarce. The results of HU therapy were evaluated in 40 patients with hyperproliferative manifestations of primary (n = 32), post-polycythemia vera (n = 6), or post-essential thrombocythemia (n = 2) myelofibrosis. Median interval between diagnosis and HU start was 6.2 months (range 0-141.7). Reasons for treatment were constitutional symptoms (55%), symptomatic splenomegaly (45%), thrombocytosis (40%), leukocytosis (28%), pruritus (10%), and bone pain (8%). The starting dose was 500 mg/day, subsequently adjusted to the individual efficacy and tolerability. Response was bone pain 100%, constitutional symptoms 82%, pruritus 50%, splenomegaly 40%, and anemia 12.5%. According to the International Working Group for Myelofibrosis Research and Treatment criteria, clinical improvement was achieved in 16 patients (40%). Median duration of response was 13.2 months (range 3-126.2). Worsening of the anemia or appearance of pancytopenia were observed in 18 patients, requiring administration of erythropoietin-stimulating agents (n = 17) and/or danazol (n = 9). Oral or leg ulcers appeared in five patients and one had gastrointestinal symptoms. HU is an effective and generally well-tolerated therapy for the hyperproliferative manifestations of MF. The accentuation of the anemia often induced by HU is usually manageable with concomitant treatment.

Platelet turnover, coagulation factors, and soluble markers of platelet and endothelial activation in essential thrombocythemia: relationship with thrombosis occurrence and JAK2 V617F allele burden

Patients with essential thrombocythemia (ET) have an increased frequency of thrombosis, but the relationship of both thrombosis and JAK2 V617F allele burden with platelet turnover, acquired activated protein C resistance (aAPCR), and levels of coagulation factors and soluble markers of platelet, and endothelial activation is not well known. In 53 ET patients (26 with a history of thrombosis), reticulated platelets (RP) percentage, aAPCR, platelet tissue factor (TF) expression, and plasma levels of TF, coagulation factors, soluble P-selectin (sP-selectin), soluble CD40 ligand (sCD40L), von Willebrand factor antigen (VWF:Ag), soluble thrombomodulin (sTM), D-dimer and prothrombin fragment 1 + 2 were compared with those in matched healthy individuals and correlated with thrombosis occurrence and JAK2 mutational load. ET patients with thrombosis had significantly higher values for RP percentage, aAPCR, and levels of factors V and VIII, VWF:Ag, sP-selectin, and sCD40L than patients without thrombosis and controls. At multivariate study, RP percentage, factor V levels, and aAPCR were independently associated with an increased risk of thrombosis. Patients with JAK2 mutation had significantly lower levels of free protein S (PS) and higher levels of TF, sP-selectin, sCD40L, VWF:Ag, and sTM than those with wild-type allele. A mutant allele dosage effect (>or= 12%) was observed for TF, sP-selectin, sCD40L, VWF:Ag, and PS levels. These results support a role for platelet turnover, factor V, and aAPCR in the thrombosis of ET as well as the association between JAK2 V617F allele burden and either decreased free PS or increased TF and soluble markers of platelet and endothelial activation.

Enoxaparin as bridging anticoagulant treatment in cardiac surgery

OBJECTIVE

To assess enoxaparin as bridging anticoagulant treatment in cardiac surgery.

METHODS

Prospective registry of those patients who underwent cardiac surgery in our centre between December 2003 and June 2004 and required long-term anticoagulation. Subcutaneous enoxaparin was used as bridging anticoagulant treatment according to a pre-established protocol. The global thromboembolic risk was carefully assessed in all patients. All patients were followed up for 3 months.

RESULTS

Of 140 patients who were included (mean (SD) age 66 (11); 49% female), 51 were already receiving long-term acenocumarol treatment before the index intervention. 50% of the patients were at high or very high risk for thromboembolic events in the postoperative period. The mean (SD) number of days between surgery and the first dose of anticoagulant was 2.01 (7) for acenocumarol and 1 (1.01) for enoxaparin. The mean (SD) daily dose of enoxaparin was 1.1 (0.27) mg/kg. Six thromboembolic events (4.3%; 95% CI 1.6 to 9.1) occurred, but only four of them were plausibly related to enoxaparin (2.9%; 95% CI 0.8 to 7.1). Six major haemorrhagic events (4.3%; 95% CI 1.6 to 9.1) occurred, but only three were plausibly related to enoxaparin (2.1%; 95% CI 0.4 to 6.1).

CONCLUSIONS

These findings show a reasonable rate of adverse events using enoxaparin as bridging anticoagulant treatment in cardiac surgery. Randomised studies are necessary to evaluate the real efficacy and safety of enoxaparin as bridging anticoagulant treatment in cardiac surgery.

Increased platelet, leukocyte, and coagulation activation in primary myelofibrosis

Platelet and leukocyte activation has been demonstrated in polycythemia vera (PV) and essential thrombocythemia (ET), but such information is limited in primary myelofibrosis (PMF). Platelet, leukocyte, endothelial, and coagulation activation status was assessed in 26 PMF patients and compared with data from 22 age- and sex-matched healthy individuals. Study included flow cytometry assessment of platelet P-selectin expression [at baseline and after adenosine diphosphate (ADP), thrombin and arachidonic acid stimulation], platelet-neutrophil and platelet-monocyte complexes, and CD11b expression in neutrophils and monocytes. Additionally, soluble P-selectin, sCD40L, tissue factor, thrombomodulin, prothrombin fragment 1 + 2 (F1 + 2), and D-dimer were measured by enzyme-linked immunosorbent assays. The above parameters were correlated with the patients' clinical data and presence of the JAK2 V617F mutation. Compared with controls, PMF patients had increased baseline platelet activation, as shown by significantly higher levels of soluble and platelet P-selectin expression, and also higher percentages of platelet-monocyte complexes. Neutrophil and monocyte CD11b expression was significantly higher in patients with the JAK2 mutation than in those with wild-type allele or the controls. Endothelial and coagulation activation, as demonstrated by increased plasma levels of thrombomodulin and F1 + 2, was also found in PMF, with patients with the JAK2 mutation showing significantly higher values of F1 + 2 than those with wild-type allele. In conclusion, PMF patients have platelet, leukocyte, endothelial, and coagulation activation similar to that in PV and ET. CD11b overexpression and F1 + 2 are correlated with the presence of the JAK2 mutation.

Abdominal Computed Tomography Predicts Progression in Patients With Rai Stage 0 Chronic Lymphocytic Leukemia

Purpose

Whether computed tomography (CT) should be routinely included in the diagnostic work-up in patients with chronic lymphocytic leukemia (CLL) has not yet been determined. The aim of this study was to analyze the prognostic significance of abdominal CT in patients with CLL in Rai clinical stage 0.

Patients and Methods

Abdominal CT was performed at diagnosis in 140 patients consecutively diagnosed with CLL in Rai stage 0 disease.

Results

An abnormal abdominal CT was found in 38 patients (27%). Abnormal CT correlated with increased bone marrow infiltration (P = .024), high lymphocyte count (P = .001), increased ZAP-70 expression (P = .003), and short lymphocyte doubling time (LDT; P = .007). Patients with abnormal CT progressed more frequently and had a shorter time to progression than those with normal CT (median, 3.5 years v not reached, respectively; P < .001) and required earlier treatment intervention. In a multivariate analysis, only high ZAP-70 expression (relative risk = 3.60) and an abnormal abdominal CT (RR = 2.71) correlated with disease progression.

Conclusion

In this series, an abnormal abdominal CT was a strong predictor of progression in patients with early-stage CLL. The inclusion of CT scans in the initial work-up of patients with early clinical stage on clinical grounds can, therefore, provide relevant clinical information.

Essential thrombocythemia in young individuals: frequency and risk factors for vascular events and evolution to myelofibrosis in 126 patients

The frequency of vascular events and evolution to myelofibrosis (MF) in young individuals with essential thrombocythemia (ET) is not well known. The incidence and predisposing factors to such complications was studied in 126 subjects diagnosed with ET at a median age of 31 years (range: 5-40). Overall survival and probability of survival free of thrombosis, bleeding and MF were analyzed by the Kaplan-Meier method and the presence of the Janus Kinase 2 (JAK2) V617F mutation correlated with the appearance of such complications. The JAK2 mutation (present in 43% of patients) was associated with higher hemoglobin (Hb) (P<0.001) and lower platelets at diagnosis. With a median follow-up of 10 years (range: 4-25), 31 thrombotic events were registered (incidence rate: 2.2 thromboses/100 patients/year). When compared with the general population, young ET patients showed a significant increase in stroke (odds ratio 50, 95% CI: 21.5-115) and venous thromboses (odds ratio 5.3, 95% CI: 3.9-10.6). Thrombosis-free survival was 84% at 10 years, with tobacco use being associated with higher risk of thrombosis. Actuarial freedom from evolution to MF was 97% at 10 years. In conclusion, young ET patients have thrombotic events, especially stroke and venous thrombosis, more frequently than generally considered, whereas they rarely transform to MF.

Increased platelet and leukocyte activation as contributing mechanisms for thrombosis in essential thrombocythemia and correlation with the JAK2 mutational status

BACKGROUND AND OBJECTIVES

The mechanisms accounting for the increased risk of thrombosis in patients with essential thrombocythemia (ET) are not well known. The aim of the present study was to ascertain the role of platelet and leukocyte activation in the thrombosis of ET.

DESIGN AND METHODS

The activation status of platelets and leukocytes was assessed by flow cytometry studies in 49 patients with ET (22 with previous thrombosis and 27 without a history of thrombosis) and in a group of age- and sex-matched healthy individuals. The assessment included platelet P-selectin expression (measured both at baseline and after stimulation with ADP, thrombin, arachidonic acid (AA), and collagen), platelet-neutrophil and platelet-monocyte complexes, determination of CD11b in the neutrophils and monocytes, and expression of tissue factor in the monocytes (mTF). The JAK2 V617F mutation was studied and correlated with platelet and leukocyte activation.

RESULTS

As compared with controls, ET patients had significantly higher values of baseline P-selectin and thrombin- and AA-induced platelet P-selectin expression, as well as higher platelet-neutrophil and platelet-monocyte complexes, neutrophil CD11b expression and baseline mTF expression. Platelet P-selectin, monocyte CD11b, and lipopolysaccharide-induced mTF expression was significantly higher in ET patients with a history of thrombosis than in patients without thrombosis. Patients with the JAK2 V617F mutation or thrombosis showed higher baseline and AA-induced platelet P-selectin expression than did those without thrombosis.

INTERPRETATION AND CONCLUSIONS

These results would support a role for platelet and monocyte activation in the thrombosis of ET. In these patients, the presence of the JAK2 V617F mutation is associated with higher platelet activation.

Frequency and risk factors for thrombosis in idiopathic myelofibrosis: analysis in a series of 155 patients from a single institution

Thrombosis is a frequent complication of polycythemia vera and essential thrombocythemia, but its incidence and predisposing factors in idiopathic myelofibrosis (IM) are unknown. In 18 (11.6%) of 155 patients diagnosed with IM in a single institution, 31 thrombotic events (19 arterial, 12 venous) were registered after a mean follow-up of 4.2 (s.d.: 4.5) years. In six patients, the thrombosis was simultaneous to or appeared a few months before IM diagnosis and 14 had one or more thrombotic episodes. When compared with the general population, a significant increase was observed in the incidence of venous thrombosis (odds ratio 17.5, 95% confidence interval: 10.3-31.4). At multivariate analysis, the initial variables associated with an increased risk of thrombosis were thrombocytosis (platelets >450 x 10(9)/l, P=0.001), presence of one cardiovascular risk factor (arterial hypertension, smoking, hypercholesterolemia, or diabetes, P=0.003), cellular phase of myelofibrosis (P=0.005), and Hb >11 g/dl (P=0.02). Considering post-diagnosis events, the 5-year thrombosis-free survival probability was 90.4% in the series, 80.6% for patients with platelets >450 x 10(9)/l, 82.6% for patients with one cardiovascular risk factor, and 85.1% for those in cellular phase. These results indicate an increased thrombotic risk for IM patients with hyperproliferative features and/or coexistent cardiovascular risk factors.

Efficacy and tolerability of danazol as a treatment for the anaemia of myelofibrosis with myeloid metaplasia: long-term results in 30 patients

Androgens are considered the treatment of choice for the anaemia of myelofibrosis with myeloid metaplasia (MMM). Good results have been reported in a few patients treated with danazol, a synthetic attenuated androgen. The long-term efficacy and tolerability of danazol as treatment for the anaemia of MMM was evaluated in 30 patients, who received 600 mg/d, with progressive tapering to the minimum effective dose in the responders after 6 months. Complete response (CR) was defined as transfusion cessation with normal Hb and partial response (PR) as an Hb increase >/=1.5 g/dl with transfusion-independent Hb values >10 g/dl maintained for at least 8 weeks. Median follow-up was 20.5 months (range: 3.5-58 months). Response was achieved in 11 patients (37%), including eight CRs and three PRs. Median time to response was 5 months (range: 1-9 months). Four patients stopped responding at 6-24 months, two responders discontinued treatment because of toxicity, and five maintained response at 3.5-42 months. Pretreatment variables associated with response were lack of transfusion requirement (P= 0.001) and higher Hb at treatment start (P= 0.02). Toxicity was usually moderate, leading to treatment withdrawal in only two cases. Danazol is effective and well tolerated in a substantial proportion of MMM patients with anaemia.

Successful treatment by selective arterial embolization of severe retroperitoneal hemorrhage secondary to bone marrow biopsy in post-polycythemic myelofibrosis

Severe retroperitoneal hemorrhage represents an infrequent and serious complication of bone marrow biopsy. A 53-year-old man, diagnosed with polycythemia vera 12 years earlier, was submitted to a bone marrow biopsy due to the appearance of anemia with clinical and hematological features suggesting myelofibrotic transformation, a diagnosis that was confirmed by the marrow study. At 2 h of a right anterior iliac bone marrow trephine biopsy, the patient suddenly developed severe pain in the area of the biopsy, with antialgic flexion of the right leg. Computed tomographic (CT) scan of the abdomen showed a 5 x 9.5 cm hematoma in the right iliac and psoas muscles. The patient was initially managed with analgesics and transfusional support, but the pain persisted and a continuous fall in the hematocrit was observed in the following days. Angiographic examination of the right external iliac artery showed contrast extravasation arising from the circumflex iliac branch, which was embolized using polivinyl alcohol particles and one coil. Following such procedure, the patient recovered uneventfully and was discharged in good condition a few days later. This case illustrates the effectiveness of an endovascular approach in providing a fast and minimally invasive treatment for this life-threatening complication of bone marrow trephine biopsy.

Salvage treatment with etoposide (VP-16), ifosfamide and cytarabine (Ara-C) for patients with recurrent primary central nervous system lymphoma

BACKGROUND

Survival of patients with primary central nervous system lymphoma (PCNSL) has improved with methotrexate-based combination regimens and radiotherapy (RT). However, the prognosis of patients who fail or relapse after initial response is poor. Very little data is available on salvage treatment at recurrence.

PATIENTS AND METHODS

Sixteen immunocompetent patients (13 males/three females, median age 54 yr) with refractory (one patient) or recurrent (15 patients) PCNSL, homogeneously treated at diagnosis with the cyclophosphamide, doxorubicin, vincristine, dexamethasone/carmustine, vincristine, cytarabine and methotrexate (CHOD/BVAM) and RT regimen, received etoposide (VP-16), ifosfamide and cytarabine (Ara-C) (VIA) chemotherapy as a salvage treatment. VIA included etoposide 100 mg/m2/d days 1-3, ifosfamide 1000 mg/m2/d days 1-5, and cytarabine 2000 mg/m2/12 h day 1. The therapy was repeated every 28 d for a total of planned six cycles.

RESULTS

Median time between first complete response (CR) and relapse was 19 months (range: 6-46 months). Thirteen patients (81%) had a performance status <or=2, six had multifocal PCNSL and six (of eight tested) positive cerebrospinal fluid cytology. The median number of courses per patient was four (range: 1-6). Five patients completed the whole VIA therapy. Six patients (37%) achieved CR. After a median follow-up of 15 months for surviving patients, two have relapsed, with a median failure-free survival of 5 months. Twelve patients have died from progression of PCNSL, with a 12-month overall survival of 41% [95% confidence interval (CI): 16-66]. The major toxicity was World Health Organization grade 2-4 neutropenia (69% of patients) and thrombocytopenia (50%). Five patients had grade 3-4 infectious complications. Finally, one patient developed a severe but reversible ifosfamide encephalopathy.

CONCLUSION

The data presented show that the chemotherapy VIA is an effective salvage regimen for patients with recurrent PCNSL.