Peter C. Huijgens

Underlying disorders associated with severe early-onset preeclampsia

OBJECTIVE Our purpose was to determine whether patients with severe early-onset preeclampsia have hemostatic or metabolic abnormalities that are associated with a tendency to vascular thrombosis. STUDY DESIGN A total of 101 patients with a history of severe early-onset preeclampsia were tested at least 10 weeks post partum for the presence of hyperhomocysteinemia (methionine loading test), protein C, protein S, and antithrombin III deficiency, activated protein C resistance, lupus anticoagulant, and immunoglobulin G and/or M anticardiolipin antibodies. RESULTS Of the 101 patients, 39 (38.6%) had chronic hypertension. Of the 85 patients tested for coagulation disturbances, 21 (24.7%) had protein S deficiency. Of the 50 patients tested for activated protein C resistance, 8 (16.0%) were positive. Of the 79 patients tested for hyperhomocysteinemia, 14 (17.7%) had a positive methionine loading test. Finally, 95 patients were tested for anticardiolipin antibodies; 27 (29.4%) had detectable immunoglobulin G and/or M anticardiolipin antibodies. CONCLUSION Patients with a history of severe early-onset preeclampsia should be screened for protein S deficiency, activated protein C resistance, hyperhomocysteinemia, and anticardiolipin antibodies, since these results may have an impact on counseling for and pharmacologic management in future pregnancies.

Phase III Trial of Consolidation Therapy With Yttrium-90–Ibritumomab Tiuxetan Compared With No Additional Therapy After First Remission in Advanced Follicular Lymphoma

PURPOSE We conducted an international, randomized, phase III trial to evaluate the efficacy and safety of consolidation with yttrium-90 ((90)Y)-ibritumomab tiuxetan in patients with advanced-stage follicular lymphoma in first remission. PATIENTS AND METHODS Patients with CD20(+) stage III or IV follicular lymphoma, who achieved a complete response (CR)/unconfirmed CR (CRu) or partial response (PR) after first-line induction treatment, were randomly assigned to receive (90)Y-ibritumomab tiuxetan (rituximab 250 mg/m(2) on day -7 and day 0 followed on day 0 by (90)Y-ibritumomab tiuxetan 14.8 MBq/kg; maximum of 1,184 MBq) or no further treatment (control). The primary end point was progression-free survival (PFS), which was calculated from the time of random assignment. RESULTS A total of 414 patients (consolidation, n = 208; control, n = 206) were enrolled at 77 centers. (90)Y-ibritumomab tiuxetan consolidation significantly prolonged median PFS (after a median observation time of 3.5 years) in all patients (36.5 v 13.3 months in control arm; hazard ratio [HR] = 0.465; P < .0001) and regardless of whether patients achieved PR (29.3 v 6.2 months in control arm; HR = 0.304; P < .0001) or CR/CRu (53.9 v 29.5 months in control arm; HR = 0.613; P = .0154) after induction treatment. Median PFS with consolidation was prolonged in all Follicular Lymphoma International Prognostic Index risk subgroups. After (90)Y-ibritumomab tiuxetan consolidation, 77% of patients in PR after induction converted to CR/CRu, resulting in a final CR rate of 87%. The most common toxicity with (90)Y-ibritumomab tiuxetan was hematologic, and grade 3 or 4 infections occurred in 8% of patients. CONCLUSION Consolidation of first remission with (90)Y-ibritumomab tiuxetan in advanced-stage follicular lymphoma is highly effective with no unexpected toxicities, prolonging PFS by 2 years and resulting in high PR-to-CR conversion rates regardless of type of first-line induction treatment.

Prognostic index for adult patients with acute myeloid leukemia in first relapse

PURPOSE The treatment of acute myeloid leukemia (AML) in first relapse is associated with unsatisfactory rates of complete responses that usually are short lived. Therefore, a clinically useful prognostic index can facilitate therapeutic decision making and evaluation of investigational treatment strategies at relapse of AML. PATIENTS AND METHODS A prognostic score is presented based on the multivariate analysis of 667 AML patients in first relapse among 1,540 newly diagnosed non-M3 AML patients (age 15 to 60 years) entered onto three successive Dutch-Belgian Hemato-Oncology Cooperative Group and the Swiss Group for Clinical Cancer Research Collaborative Group trials. RESULTS Four clinically relevant parameters are included in this index (ie, length of relapse-free interval after first complete remission, cytogenetics at diagnosis, age at relapse, and whether previous stem-cell transplantation was performed). Using this stratification system, three risk groups were defined: a favorable prognostic group A (overall survival [OS] of 70% at 1 year and 46% at 5 years), an intermediate-risk group B (OS of 49% at 1 year and 18% at 5 years), and a poor-risk group C (OS of 16% at 1 year and 4% at 5 years). CONCLUSION The prognostic index estimates the outcome of AML patients in first relapse using four commonly applied clinical parameters and might identify patients who are candidates for salvage and investigational therapy.

Continuous infusion of low-dose 5-Aza-2′-deoxycytidine in elderly patients with high-risk myelodysplastic syndrome

There is no standard therapy for elderly patients with high-risk myelodysplastic syndrome (MDS). The treatment options of low-dose Ara-C and haematopoietic growth factors are disappointing in regard to response rate or response duration. We tested the treatment with a 72-h continuous infusion of low-dose 5-Aza-2′-deoxycytidine (DAC) in a group of 29 elderly patients with high-risk MDS. In 15 patients (54%) we observed a response. Eight complete responses were reached, even among patients with bad prognostic cytogenetic findings. The actuarial median survival from the start of the therapy was 46 weeks. The only (and major) toxicity was myelosuppression, leading to a prolonged cytopenic period and thus leading to five toxic deaths (17%) in this high-risk patient group. We conclude that DAC is an effective drug in the treatment of MDS patients and that it probably works via its cytotoxic activity. Myelotoxicity is its major adverse effect.

High Prognostic Impact of Flow Cytometric Minimal Residual Disease Detection in Acute Myeloid Leukemia: Data From the HOVON/SAKK AML 42A Study

PURPOSE Half the patients with acute myeloid leukemia (AML) who achieve complete remission (CR), ultimately relapse. Residual treatment-surviving leukemia is considered responsible for the outgrowth of AML. In many retrospective studies, detection of minimal residual disease (MRD) has been shown to enable identification of these poor-outcome patients by showing its independent prognostic impact. Most studies focus on molecular markers or analyze data in retrospect. This study establishes the value of immunophenotypically assessed MRD in the context of a multicenter clinical trial in adult AML with sample collection and analysis performed in a few specialized centers. PATIENTS AND METHODS In adults (younger than age 60 years) with AML enrolled onto the Dutch-Belgian Hemato-Oncology Cooperative Group/Swiss Group for Clinical Cancer Research Acute Myeloid Leukemia 42A study, MRD was evaluated in bone marrow samples in CR (164 after induction cycle 1, 183 after cycle 2, 124 after consolidation therapy). RESULTS After all courses of therapy, low MRD values distinguished patients with relatively favorable outcome from those with high relapse rate and adverse relapse-free and overall survival. In the whole patient group and in the subgroup with intermediate-risk cytogenetics, MRD was an independent prognostic factor. Multivariate analysis after cycle 2, when decisions about consolidation treatment have to be made, confirmed that high MRD values (> 0.1% of WBC) were associated with a higher risk of relapse after adjustment for consolidation treatment time-dependent covariate risk score and early or later CR. CONCLUSION In future treatment studies, risk stratification should be based not only on risk estimation assessed at diagnosis but also on MRD as a therapy-dependent prognostic factor.

Clinical effectiveness of leucoreduced, pooled donor platelet concentrates, stored in plasma or additive solution with and without pathogen reduction

Pathogen reduction (PR) of platelet products increases costs and available clinical studies are equivocal with respect to clinical and haemostatic effectiveness. We conducted a multicentre, open‐label, randomized, non‐inferiority trial comparing the clinical effectiveness of buffy‐coat derived leucoreduced platelet concentrates (PC) stored for up to 7 d in plasma with platelets stored in platelet additive solution III (PASIII) without and with treatment with amotosalen‐HCl/ultraviolet‐A (UVA) photochemical pathogen reduction (PR‐PASIII). Primary endpoint of the study was 1‐h corrected count increment (CCI). Secondary endpoints were 24‐h CCI, bleeding, transfusion requirement of red cells and PC, platelet transfusion interval and adverse transfusion reactions. Compared to plasma‐PC, in the intention to treat analysis of 278 evaluable patients the mean difference for the 1‐h CCI of PR‐PASIII‐PC and PASIII‐PC was −31% (P < 0·0001) and −9% (P = n.s.), respectively. Twenty‐seven patients (32%) had bleeding events in the PR‐PASIII arm, as compared to 19 (19%) in the plasma arm and 14 (15%) in the PASIII arm (P = 0·034). Despite the potential advantages of pathogen (and leucocyte) inactivation of amotosalen‐HCl/UVA‐treated platelet products, their clinical efficacy is inferior to platelets stored in plasma, warranting a critical reappraisal of employing this technique for clinical use.

Drug-induced histone eviction from open chromatin contributes to the chemotherapeutic effects of doxorubicin

DNA topoisomerase II inhibitors are a major class of cancer chemotherapeutics, which are thought to eliminate cancer cells by inducing DNA double-strand breaks. Here we identify a novel activity for the anthracycline class of DNA topoisomerase II inhibitors: histone eviction from open chromosomal areas. We show that anthracyclines promote histone eviction irrespective of their ability to induce DNA double-strand breaks. The histone variant H2AX, which is a key component of the DNA damage response, is also evicted by anthracyclines, and H2AX eviction is associated with attenuated DNA repair. Histone eviction deregulates the transcriptome in cancer cells and organs such as the heart, and can drive apoptosis of topoisomerase-negative acute myeloid leukaemia blasts in patients. We define a novel mechanism of action of anthracycline anticancer drugs doxorubicin and daunorubicin on chromatin biology, with important consequences for DNA damage responses, epigenetics, transcription, side effects and cancer therapy.

Long-term effects of vincristine on the peripheral nervous system.

SummaryForty patients with Non-Hodgkins Lymphoma treated with vincristine between 1984 and 1990 (cumulative dose 12 mg in 18–24 weeks) were investigated in order to evaluate the long term effects of vincristine on the peripheral nervous system. The patients were interviewed with emphasis on neuropathic symptoms. Physical and quantitative sensory examination with determination of vibratory perception and thermal discrimination thresholds were performed, four to 77 months (median 34 months) after vincristine treatment. Twenty-seven patients reported neuropathic symptoms. In 13 of these 27 patients symptoms were still present at the time of examination. In these patients sensory signs and symptoms predominated. In the other 14 patients symptoms had been present in the past. Symptoms persisted maximally 40 months since cessation of therapy. There was no age difference between patients with and without complaints at the time of examination. Normal reflexes were found in two third of patients. Neuropathic complaints were not very troublesome on the long term. It is concluded that with the above mentioned vincristine dose schedule signs and symptoms of vincristine neuropathy are reversible for a great deal and prognosis is fairly good.

Proteoglycans guide SDF-1-induced migration of hematopoietic progenitor cells

Stromal cell‐derived factor‐1 (SDF‐1) is a chemoattractant involved in hematopoietic progenitor cell (HPC) trafficking to the bone marrow. We studied the role of bone marrow endothelial proteoglycans (PGs) in SDF‐1‐mediated migration of HPC using a transwell assay. A subclone of progenitor cell line KG‐1 (KG‐1v) was used, displaying CXCR4‐dependent transmigration. Cell surface PGs on bone marrow endothelial cell line 4LHBMEC did not mediate SDF‐1‐induced transendothelial migration. In contrast, transwell filters precoated with various glycosaminoglycans (GAGs) enhanced migration toward SDF‐1. SDF‐1‐induced migration was reduced by degradation of heparan sulfate in subendothelial matrix produced by 4LHBMEC. The stimulating effect of GAGs was caused by the formation of a stable haptotactic SDF‐1 gradient, as SDF‐1 bound to immobilized GAGs and triggered migration. Soluble heparan sulfate enhanced SDF‐1‐induced migration dose‐dependently, suggesting that SDF‐1‐heparan sulfate complexes optimized SDF‐1 presentation. In conclusion, we provide evidence that PGs in the subendothelial matrix establish an SDF‐1 gradient guiding migrating HPC into the bone marrow.

Performance characteristics of a 511-keV collimator for imaging positron emitters with a standard gamma-camera

Line-source experiments were conducted to assess the performance of a gamma-camera equipped with a specially designed 511-keV collimator for the planar imaging of positron emitters. The results were compared with the camera performance with routinely used collimators and radionuclides (thallium-201, technetium-99m and gallium-67). With positron emitters, scatter contributed less to the widening of the line spread function than with radionuclides emitting lower photon energies. These observations can be explained by the relative deterioration in the discrimination power of the gamma-camera to reject scattered radiation at low energies. Planar 511-keV imaging may provide relevant clinical information, as we showed by fluorodeoxyglucose studies in a patient with a myocardial infarction and in a patient with a malignant lymphoma. It is concluded that positron emitters can be effectively applied for planar imaging with the generally available gamma-cameras. This study implies that radiotracers developed for positron emission tomography may find a place in the practice of conventional nuclear medicine.