Two novel high-risk adult B-cell acute lymphoblastic leukemia subtypes with high expression of CDX2 and IDH1/2 mutations.

The genetic basis of leukemogenesis in adults with B-cell acute lymphoblastic leukemia (B-ALL) is largely unclear, and its clinical outcome remains unsatisfactory. This study aimed to advance the understanding of biological characteristics, improve disease stratification, and identify molecular targets of adult B-ALL. Adolescents and young adults (AYA) (15 to 39 years old, n = 193) and adults (40 to 64 years old, n = 161) with Philadelphia chromosome-negative (Ph-) B-ALL were included in this study. Integrated transcriptomic and genetic analyses were used to classify the cohort into defined subtypes. Of the 323 cases included in the RNA sequencing analysis, 278 (86.1%) were classified into 18 subtypes. The ZNF384 subtype (22.6%) was the most prevalent, with 2 novel subtypes (CDX2-high and IDH1/2-mut) identified among cases not assigned to the established subtypes. The CDX2-high subtype (3.4%) was characterized by high expression of CDX2 and recurrent gain of chromosome 1q. The IDH1/2-mut subtype (1.9%) was defined by IDH1 R132C or IDH2 R140Q mutations with specific transcriptional and high-methylation profiles. Both subtypes showed poor prognosis and were considered inferior prognostic factors independent of clinical parameters. Comparison with a previously reported pediatric B-ALL cohort (n = 1003) showed that the frequencies of these subtypes were significantly higher in AYA/adults than in children. We delineated the genetic and transcriptomic landscape of adult B-ALL and identified 2 novel subtypes that predict poor disease outcomes. Our findings highlight the age-dependent distribution of subtypes, which partially accounts for the prognostic differences between adult and pediatric B-ALL.

Utility of allogeneic stem cell transplantation for adult Ph+ALL with complete molecular remission.

This study aimed to investigate the usefulness of allogeneic stem cell transplantation (allo-SCT) for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) in the first complete remission (CR1) with complete molecular remission (CMR). We compared the outcomes between Ph+ALL patients who did or did not undergo allo-SCT in CR1. We included patients enrolled in the prospective clinical studies in the tyrosine kinase inhibitor era conducted by the Japan Adult Leukemia Study Group, who achieved CMR within 3 months. A total of 147 patients (allo-SCT: 101; non-SCT: 46) were eligible for this analysis. In the multivariate analyses, allo-SCT was significantly associated with both superior overall survival (OS) (adjusted hazard ratio (aHR): 0.54; 95% CI: 0.30-0.97; p = .04) and relapse-free survival (RFS) (aHR: 0.21; 95% CI: 0.12-0.38; p < .001). The 5-year adjusted OS and RFS were 73% and 70% in the allo-SCT cohort, whereas they were 50% and 20% in the non-SCT cohort. Despite the higher non-relapse mortality (aHR: 3.49; 95% CI: 1.17-10.4; p = .03), allo-SCT was significantly associated with a lower relapse rate (aHR: 0.10; 95% CI: 0.05-0.20; p < .001). In addition, allo-SCT was also associated with superior graft-versus-host disease-free, relapse-free survival (aHR: 0.43; 95% CI: 0.25-0.74; p = .002). Propensity score-matched analyses confirmed the results of the multivariate analyses. In patients who achieved CMR within 3 months, allo-SCT in CR1 had superior survival and lower relapse compared with the non-SCT cohort.

Fostamatinib for the treatment of Japanese patients with primary immune thrombocytopenia: A phase 3, placebo-controlled, double-blind, parallel-group study.

Fostamatinib, a spleen tyrosine kinase inhibitor, has been approved for the treatment of chronic primary immune thrombocytopenia (ITP) in the United States, Canada and some European countries. We conducted a phase 3, placebo-controlled, double-blind, parallel-group study to evaluate the efficacy and safety of fostamatinib in Japanese patients with primary ITP. Thirty-four patients were randomised to fostamatinib (n = 22) or placebo (n = 12) at 100-150 mg twice a day for 24 weeks. Stable responses (platelet ≥50 000/µl at ≥4 of the 6 visits from weeks 14 to 24) were observed in eight (36%) patients on fostamatinib and in none of the patients on placebo (p = 0.030). Overall responses (platelet ≥50 000/µl at ≥1 of the 6 visits from weeks 2 to 12) were seen in 10 (45%) patients on fostamatinib and in none of the patients on placebo (p = 0.006). Patients on fostamatinib required rescue medication less often and experienced fewer bleeding symptoms than patients on placebo. Adverse events observed were mild or moderate and were manageable. No new safety signals were identified in Japanese patients with ITP.

Macrophage depletion using clodronate liposomes reveals latent dysfunction of the hematopoietic microenvironment associated with persistently imbalanced M1/M2 macrophage polarization in a mouse model of hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH), a hyperinflammatory syndrome, is caused by the incessant activation of lymphocytes and macrophages, resulting in damage to organs, including hematopoietic organs. Recently, we demonstrated that repeated lipopolysaccharide (LPS) treatment induces HLH-like features in senescence-accelerated (SAMP1/TA-1) mice but not in senescence-resistant control (SAMR1) mice. Hematopoietic failure in LPS-treated SAMP1/TA-1 mice was attributed to hematopoietic microenvironment dysfunction, concomitant with severely imbalanced M1 and M2 macrophage polarization. Macrophages are a major component of the bone marrow (BM) hematopoietic microenvironment. Clodronate liposomes are useful tools for in vivo macrophage depletion. In this study, we depleted macrophages using clodronate liposomes to determine their role in the hematopoietic microenvironment in SAMP1/TA-1 and SAMR1 mice. Under clodronate liposome treatment, the response between SAMR1 and SAMP1/TA-1 mice differed as follows: (1) increase in the number of activated M1 and M2 macrophages derived from newly generated macrophages and M2-dominant and imbalanced M1 and M2 macrophage polarization in the BM and spleen; (2) severe anemia and thrombocytopenia; (3) high mortality rate; (4) decrease in erythroid progenitors and B cell progenitors in the BM; and (5) decrease in the mRNA expression of erythroid-positive regulators such as erythropoietin and increase in that of erythroid- and B lymphoid-negative regulators such as interferon-γ in the BM. Depletion of residual macrophages in SAMP1/TA-1 mice impaired hematopoietic homeostasis, particularly erythropoiesis and B lymphopoiesis, owing to functional impairment of the hematopoietic microenvironment accompanied by persistently imbalanced M1/M2 polarization. Thus, macrophages play a vital role in regulating the hematopoietic microenvironment to maintain homeostasis.

[Thrombotic microangiopathy with gastrointestinal hemorrhage during carfilzomib therapy for multiple myeloma].

A 70-year-old woman was admitted to the hospital with loss of appetite and melena. She was diagnosed with multiple myeloma 7 years ago and had been on carfilzomib, lenalidomide, and dexamethasone (KRd) therapy for a month because her disease had a relapsed/refractory. On admission, her laboratory tests revealed hemolytic anemia with schizocytes, thrombocytopenia, and acute renal dysfunction. TMA (thrombotic microangiography) caused by carfilzomib was suspected. The possibility of thrombotic thrombocytopenia was considered, and steroid pulse therapy was initiated. Her condition improved significantly after she stopped taking carfilzomib, plasma exchange, hemodiafiltration, steroid pulse therapy, and abstaining from food. The previously reported cases of carfilzomib-induced TMA included fever, gastrointestinal symptoms (nausea/vomiting, diarrhea), and acute renal disorders (lower extremity edema, decreasing urine output). As far as we know, this is the first case of carfilzomib-induced TMA with bleeding as the first symptom.

von Willebrand factor activity levels are influenced by driver mutation status in polycythemia vera and essential thrombocythemia patients with well-controlled platelet counts.

von Willebrand factor ristocetin cofactor (vWF activity) and platelet count (PLT) are negatively correlated in patients with polycythemia vera (PV) and essential thrombocythemia (ET). However, vWF activity does not always normalize upon controlling PLT in those patients. To address this issue, we investigated the correlation between vWF activity and PLT in PV and ET patients. The negative correlation between vWF activity and PLT was stronger in calreticulin mutation-positive (CALR+) ET than in Janus kinase 2 mutation-positive (JAK2+) PV or ET groups. When PLT were maintained at a certain level (<600 × 109 /L), low vWF activity (<50%) was more frequently observed in JAK2+ PV patients than in JAK2+ ET (p = .013) or CALR+ ET (p = .013) groups, and in PV and ET patients with ≥50% JAK2+ allele burden than in those with allele burden <50% (p = .015). High vWF activity (>150%) was more frequent in the JAK2+ ET group than in the CALR+ ET group (p = .005), and often associated with vasomotor symptoms (p = .002). This study suggests that some patients with JAK2+ PV or ET have vWF activity outside the standard range even with well-controlled PLT, and that the measurement of vWF activity is useful for assessing the risk of thrombosis and hemorrhage.

Relationship between Carnitine Deficiency and Tyrosine Kinase Inhibitor Use in Patients with Chronic Myeloid Leukemia.

BACKGROUND: Some chemotherapeutic agents cause carnitine deficiency, which causes general fatigue. However, there is no study on carnitine deficiency in patients with chronic myeloid leukemia (CML) during tyrosine kinase inhibitor (TKI) therapy. OBJECTIVE: In this study, we investigated carnitine concentrations in patients with CML receiving TKI therapy. METHOD: This study included patients with well-controlled CML. Total carnitine and free carnitine concentrations were evaluated using the enzyme cycling method. The brief fatigue inventory (BFI) and cancer fatigue scale (CFS) were used to assess general fatigue developed during TKI therapy. RESULTS: Fifty-five patients on TKI therapy were included. Of these, 12 (21.8%) patients had low free carnitine concentrations. Free carnitine concentrations were higher in men than in women. Younger age was closely associated with lower free carnitine concentrations. TKI type, TKI dose, treatment response, or therapy duration were not associated with free carnitine concentrations. None of the scores (the global fatigue score with the BFI and CFS score) correlated with carnitine concentrations. Concentrations of free carnitine in patients in the treatment-free remission group were slightly higher than those in the TKI group, with only 9.1% having a low concentration of free carnitine. CONCLUSION: Carnitine deficiency is probably not a major cause of general fatigue but may occur in patients with CML receiving TKI therapy.

Consolidation with 90 Yttrium-ibritumomab tiuxetan after bendamustine and rituximab for relapsed follicular lymphoma.

Bendamustine and rituximab (BR) are widely used in patients with follicular lymphoma (FL) previously treated with conventional immunochemotherapy, but the role of consolidation radioimmunotherapy in these patients is unknown. This study evaluated the efficacy and safety of consolidation with 90 Yttrium-ibritumomab tiuxetan (90 Y-IT) after re-induction therapy with BR in patients with previously treated FL. This study included adult patients with relapsed FL who had undergone one or two prior therapies. Re-induction therapy with BR was administered every 4 weeks up to 4-6 cycles. If patients achieved at least partial response, 90 Y-IT was administered as consolidation therapy. The primary endpoint was 2-year progression-free survival (PFS) after consolidation. A total of 24 FL patients (median age 60 years) who had undergone one (n = 17) or two (n = 7) prior treatments received BR. After BR therapy, 22 patients proceeded to consolidation with 90 Y-IT, resulting in an overall 88% response rate to the protocol treatment. Within a median observation period of 46.8 months, the estimated 2-year PFS rate after the consolidation among the 22 patients receiving 90 Y-IT was 59% (95% confidence interval [CI], 38%-77%). Patients whose remission after previous treatment had lasted ≥2 years had a significantly higher 2-year PFS rate than patients whose remission after previous treatment had been <2 years (68% vs. 33%, Wilcoxon p = 0.0211). Major adverse events during the protocol treatment and within 2 years after the consolidation were hematological toxicities, but they were generally acceptable. Consequently, the estimated 2-year overall survival after the consolidation was 95% (95% CI, 74%-99%). In conclusion, in a subset of patients with previously treated FL, 90 Y-IT consolidation after BR re-induction conferred a durable remission, indicating that consolidation therapy using 90 Y-IT may be a novel therapeutic option for patients with relapsed FL (UMIN000008793).

Increased Arbekacin Clearance in Patients With Febrile Neutropenia.

BACKGROUND: Arbekacin (ABK) is used to treat infections caused by methicillin-resistant Staphylococcus aureus and is used widely for the treatment of febrile neutropenia (FN). As ABK has a narrow therapeutic concentration window, the dosage must be adjusted via therapeutic drug monitoring. However, the influence of the physiology of patients with FN on the pharmacokinetic (PK) parameters of ABK remains unclear. Therefore, we examined this influence on ABK PK parameters. METHOD: We performed a retrospective cohort study using data from patients with a hematologic malignancy who were ≥18 years and had been administered ABK. We excluded patients who did not receive therapeutic drug monitoring and had an estimated glomerular filtration rate (eGFR) of <30 mL/min, because clinically sufficient data would not be available. RESULT: Of the 99 enrolled patients, 25 did not have FN and 74 had FN. Arbekacin clearance (CLabk) was shown to correlate with eGFR in patients with FN (r = 0.32, P = 0.0062) and without FN (r = 0.50, P = 0.01). CLabk was higher in patients with FN than in those without FN. In addition, in the eGFR of <100 mL/min group (normal renal function), CLabk and CLabk/eGFR were also higher in patients with FN than in those without FN. CONCLUSIONS: CLabk was increased in patients with FN and normal renal function; therefore, we propose an increased ABK dose for patients with FN and normal renal function.

Identification of a Novel ACVRL1 Gene Mutation (c.100T>A, p.Cys34Ser) in a Japanese Patient with Possible Hereditary Hemorrhagic Telangiectasia (Osler-Weber-Rendu Disease).

Hereditary hemorrhagic telangiectasia (HHT; also known as Osler-Weber-Rendu disease) is an autosomal dominant genetic disorder that causes frequent epistaxis, mucocutaneous telangiectasia, and visceral arteriovenous malformations. Four genes (ENG, ACVRL1, SMAD4, and GDF2) have been identified as pathogenic in HHT. We describe the case of a 50-year-old Japanese man highly suspected of having HHT due to recurrent epistaxis, mucocutaneous telangiectasia, and a family history. Genomic analysis revealed a novel missense mutation of c.100T>A, p.Cys34Ser in the patient's ACVRL1 gene. We used 6 freeware programs to perform an in silico analysis of this mutation. The results demonstrated the mutation's high pathogenicity.

[State-of-the-art therapy for adult Philadelphia chromosome-negative acute lymphoblastic leukemia].

With pediatric-inspired chemotherapy, the survival of adult patients with Philadelphia chromosome-negative acute lymphoblastic leukemia (ALL) has improved. For standard-risk patients in the first complete remission (CR1), pediatric-inspired chemotherapy may be superior than allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, increased dose of steroid, vincristine, and L-asparaginase (L-Asp) in pediatric-inspired chemotherapy induces adverse events in certain number of adult ALL patients. Especially, the administration of L-Asp is often reduced to 60-70% for thrombosis or liver dysfunction. The optimal dose of these agents for adult ALL patients with higher age is under investigation. Moreover, minimal residual disease (MRD) >10-4 is a poor prognostic factor. The time point for the assessment of MRD should be defined. For relapsed or refractory ALL, inotuzumab ozogamicin and blinatumomab are promising antibody agents that diminish MRD and proceed to allo-HSCT.

[Antibody therapy for acute lymphoblastic leukemia].

In 2018, two novel antibody therapies, inotuzumab ozogamicin (InO) and blinatumomab, against relapsed or refractory acute lymphoblastic leukemia were approved in Japan. In InO, the antitumor drug ozogamicin is conjugated to the anti-CD22 antibody. Blinatumomab is a bispecific T cell engager antibody comprising the variable regions of the anti-CD19 and the anti-CD3 antibodies. The remission rate of InO is about 75%; however, the frequency of sinusoidal obstruction syndrome is increased when allogeneic hematopoietic cell transplantation is performed after InO treatment. Blinatumomab has a remission rate of 45-70%. The management of cytokine release syndrome during blinatumomab treatment is required in certain cases. Although both the treatments have higher remission and negativity of minimal residual disease rates compared to those in conventional chemotherapy, it is difficult to maintain remission in the long term. Allogeneic hematopoietic stem cell transplantation should be performed as commonly as possible.

[Transformation of CD5-positive nodal marginal zone lymphoma to diffuse large B-cell lymphoma].

Nodal marginal zone lymphoma (NMZL) is a form of nodal B-cell lymphoma exhibiting proliferation of abnormal lymphocytes at the circumference of the mantle zone in the lymph nodes. Although the outcome of patients with this disease is often favorable, we recently encountered a patient with a CD5-positive NMZL who was resistant to chemotherapy. A 67-year-old woman complaining of systemic lymph node swelling was referred to our hospital. After biopsy of the neck lymph node, she was diagnosed with CD5-positive NMZL. Disease progression was revealed after 16 months, and she was initially treated with chemotherapy consisting of rituximab, cyclophosphamide, vincristine, and prednisolone (R-CVP). However, this therapy was ineffective. Subsequent therapy with rituximab and bendamustine also failed to induce remission. A rebiopsy revealed that the NMZL had transformed into a diffuse large B-cell lymphoma. This patient died after 2 years from the initial diagnosis due to lymphoma progression. Cases of CD5-positive NMZL are rare; thus, it is difficult to study the clinical implications of CD5 expression in this disease. Here we describe the current understanding of CD5 expression in NMZL.

Combined treatment with benzo[a]pyrene and 1α,25-dihydroxyvitamin D3 induces expression of plasminogen activator inhibitor 1 in monocyte/macrophage-derived cells.

Benzo[a]pyrene (BaP) is an environmental pollutant found in cigarette smoke and is implicated as a causative agent of tobacco-related diseases, such as arteriosclerosis. In contrast, vitamin D signaling, which is principally mediated by conversion of vitamin D to the active form, 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3], decreases cardiovascular disease risk. However, combined treatment with BaP and 1,25(OH)2D3 enhances BaP toxicity, including BaP-DNA adduct formation. We further investigated the cross-talk between BaP and 1,25(OH)2D3 signaling pathways, and found that combined treatment with these compounds induces mRNA and protein expression of plasminogen activator inhibitor 1 (PAI-1) in monocyte/macrophage-derived THP-1 and U937 cells. Protein synthesis inhibitor treatment did not inhibit induction of the PAI-1 gene (SERPINE1) in these cells. BaP plus 1,25(OH)2D3 induced differentiation markers, inhibited cellular proliferation, and induced apoptosis and oxidative stress in these cells. Reactive oxygen species scavenger treatment suppressed apoptosis but not SERPINE1 induction in cells treated with BaP plus 1,25(OH)2D3. Thus, combined treatment with BaP and 1,25(OH)2D3 induced SERPINE1 mRNA expression in these cells through a mechanism that does not require de novo protein synthesis or reactive oxygen species production. These findings suggest that induction of the proinflammatory factor PAI-1 plays a role in BaP toxicity. Interestingly, PAI-1 knockdown decreased expression of the cell surface antigen CD14, a monocytic differentiation marker, in THP-1 cells treated with BaP plus 1,25(OH)2D3. PAI-1 induction may also be related to a function of monocytes/macrophages in response to xenobiotic and vitamin D signaling.

Final analysis of the JALSG Ph+ALL202 study: tyrosine kinase inhibitor-combined chemotherapy for Ph+ALL.

The Japan Adult Leukemia Study Group (JALSG) Ph+ALL202 study reported a high complete remission (CR) rate for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) patients treated with imatinib-combined chemotherapy. However, the long-term treatment efficacy remains uncertain. Here, we report a final analysis of the JALSG Ph+ALL202 study. The outcomes were compared with those of the JALSG ALL93 and ALL97 studies, which were conducted in the pre-imatinib era. Ninety-nine newly diagnosed Ph+ALL patients were enrolled in Ph+ALL202 (median age, 45 years; median follow-up, 4.5 years). CR was achieved in 96/99 (97%) patients. Fifty-nine of these 96 patients (61%) underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) in their first CR (CR1). The 5-year overall and disease-free survival (DFS) rates were 50 and 43%, respectively, which were significantly higher compared to those in the pre-imatinib era (15 and 19%, respectively). Multivariate analysis revealed that imatinib administration, allo-HSCT in CR1, and a white blood cell count < 30 × 109/L were favorable independent prognostic factors for long-term DFS. Improved odds of receiving allo-HSCT and a lower relapse rate leaded to good long-term outcomes. The 3-year DFS tended to be higher in PCR-negative than that in PCR-positive patients (29 vs. 14%) in the non-HSCT patients, and this tendency was also seen in the allo-HSCT patients (59 vs. 50%). The higher rate of CR upon imatinib use may have contributed to these improvements.

Features of vascular adverse events in Japanese patients with chronic myeloid leukemia treated with tyrosine kinase inhibitors: a retrospective study of the CML Cooperative Study Group database.

This study investigated the incidence rate and features of vascular adverse events (VAEs) in Japanese patients with chronic myeloid leukemia (CML) who were treated with tyrosine kinase inhibitors (TKIs). The analysis included 369 CML patients in the chronic or accelerated phases, selected from the CML Cooperative Study Group database; 25 events in 23 (6.2%) of these patients were VAEs. At the time of VAE incidence, nine patients were on treatment with imatinib, 12 with nilotinib, three with dasatinib, and one with bosutinib. VAE incidence comprised 13 cases of ischemic heart disease (IHD), eight of cerebral infarction (CI), and four of peripheral arterial occlusive disease (PAOD). IHD incidence rate in the study population was higher than that in the age-matched general population, particularly in nilotinib-treated patients, while CI incidence rate was almost equivalent. Compared with the Suita score, the SCORE chart and the Framingham score risk assessment tools detected more patients with high or very high risk of VAEs. In conclusion, incidence of IHD requires closer monitoring in nilotinib-treated patients. More detailed investigations for determining the most useful tool to predict VAE incidence and long-term analysis of therapy-related VAE cases are needed for improving safety during TKI therapy.

Mycotic pseudoaneurysm of a pulmonary artery branch caused by Cladosporium.

We report the case of a 53-year-old male with a history of acute myelogenous leukemia, who suffered the rupturing of a right-sided pulmonary artery pseudoaneurysm combined with pneumonia. He underwent a right-sided lower lobectomy. The resected lung tissue demonstrated a mycotic pseudoaneurysm of a pulmonary artery branch together with a filamentous fungal infection. Pseudoaneurysms are caused by the breaching of all layers of a blood vessel wall. The extravasated blood is trapped by the surrounding extravascular tissue or clots. Cladosporium was detected during a polymerase chain reaction-based analysis followed by DNA sequencing of formalin-fixed paraffin-embedded lung tissue samples. Although previous cases of pulmonary artery pseudoaneurysms caused by fungal infections, e.g., Candida or Aspergillus sp., have been reported, to the best of our knowledge this is the first case to involve cladosporiosis.

One percent chlorhexidine-alcohol for preventing central venous catheter-related infection during intensive chemotherapy for patients with haematologic malignancies.

A central venous catheter (CVC) is a catheter placed into a large vein, and is used for chemotherapy administration. However, there is little confirmatory data on which antiseptic-such as chlorhexidine or povidone-iodine (PI) -is more protective against CVC-related infectious complications in patients receiving intensive chemotherapy. We aimed to compare the effectiveness of 1% chlorhexidine gluconate in 70% alcohol (CH) vs. PI for skin disinfection before CVC insertion in patients receiving intensive chemotherapy. Methods We used either CH or 10% PI as skin antiseptics before CVC insertion, and assessed which agent was more protective against CVC-related infection. The participants were 112 patients with haematologic malignancies who underwent chemotherapy; a total of 292 CVCs were inserted over this period. Blood cultures were obtained when febrile neutropenia occurred. The CVC was removed and the catheter-tip qualitatively cultured when catheter-related infection was suspected. The cumulative incidence of febrile neutropenia, microbial growth from blood or catheter-tip culture, and catheter-related blood stream infection (CRBSI) was evaluated retrospectively. A univariate Cox proportional hazards model showed that CH significantly alleviated infectious complications. Notably, no case of CRBSI occurred in the CH group. Multivariate analysis, adjusted for prolonged neutropenia (>15 days) and older age (>52 years), also showed significant reduction in the cumulative incidence of microbial growth from catheter-tips in the CH group (hazard ratio = 0.146, 95% confidence interval: 0.023-0.502, p = 0.0008). Disinfection using CH, compared with PI, can potentially decrease catheter-related infection without causing adverse skin reactions in patients with haematologic malignancies.