Grading of symptoms in hyperleukocytic leukaemia: a clinical model for the role of different blast types and promyelocytes in the development of leukostasis syndrome

Symptomatic Patients with Hyperleukocytic FLT3-ITD Mutated Acute Myeloid Leukemia Might Benefit from Leukapheresis

PURPOSE

We aimed to identify subsets of patients who benefit from emergency LA and to establish a therapeutic algorithm for AML patients with hyperleukocytosis.

METHODS

In this single-center retrospective cohort study, a total of 20 consecutive patients underwent LA because of their clinical symptoms. Overall survival (OS) analysis was conducted using the Kaplan-Meier plot method. Univariate and multivariate analyses (using multiple logistic regression) were performed. At the time of diagnosis, all patients received a standard diagnostic workup for AML including FLT3-ITD mutational analysis.

RESULTS

FLT3-ITD mut AML patients receiving LA had a median OS of 437 days (range 5-2379 days) with a corresponding 14-day survival of 92.3%, while FLT3 wt AML patients displayed a significantly lower median OS of only 5 days (range 1-203 days) with a corresponding 14-day survival of 14.3% (p = 0.0001).

CONCLUSIONS

Among patients with clinical symptoms of leukostasis, the subset of FLT3-ITD mut AML patients showed a better outcome with lower early mortality after emergency LA. Based on these observations, we established a therapeutic algorithm for AML patients with hyperleukocytosis.

Genetic mutations and leukapheresis in acute myeloid leukemia: is there a link?

Acute myeloid leukemia is the most common acute leukemia in adults and up to 20% of patients present with hyperleukocytosis at the onset of the disease. The therapeutic approach involves medical support, cytoreductive treatment, and/or leukapheresis. Despite WBC count greater than 100.000/μL, not all patients develop symptoms. To clarify the role of leukapheresis in the setting of hyperleukocytotic AML, we aimed to find associations between AML morphologic subtypes and molecular alterations on presence or absence of leukostasis symptoms (and hence therapeutic vs prophylactic leukapheresis) and clinical outcomes in the cohort of 41 patients at our single center who underwent leukapheresis for hyperleukocytotic AML. There was a trend for increased WBC count, 30-day mortality, M4-M5 AML subtypes, and number of leukapheresis procedures performed in symptomatic hyperleukocytotic pts. No molecular marker was significantly associated with presence or absence of leukostasis symptoms due to small sample size, though there was a trend for increased NPM1-mutated and NPM1 + FLT3-mutated AML in asymptomatic patients and a greater proportion of symptomatic patients who were negative for all assessed molecular alterations. In conclusion, leukapheresis combined with cytoreductive treatment represents a synergic and efficient approach in the management of hyperleukocytosis especially in symptomatic patients considering the higher mortality independently from the presence of specific clonal markers whose distribution among the two groups may result more considerable with a higher number of patients.

Clinical outcomes of therapeutic leukapheresis in acute promyelocytic leukemia: A single-center retrospective cohort study

BACKGROUND

In acute promyelocytic leukemia (APL), increased cell burden in the peripheral blood due to either the disease itself or early treatment with all-trans retinoic acid could cause hyperleukocytosis (HL) before induction chemotherapy. However, therapeutic leukapheresis has seldom been used because of concerns of subsequent coagulopathy after this invasive procedure. The aim of this study was to evaluate the effects of leukapheresis in APL, especially for efficacy and safety.

METHODS

We retrospectively analyzed newly diagnosed patients with APL from January 2009 to March 2022. Among 323 patients, 85 had white blood cell count above 40 × 10⁹/L before induction chemotherapy. Thirty-nine patients were initially treated with leukapheresis, whereas the other 46 were not. Clinical and laboratory parameters between these groups were compared.

RESULTS

There was a trend toward favorable 30-day survival rate for the leukapheresis group compared with the non-leukapheresis group (76.9% and 67.4%; P = 0.24). The complications including subsequent intensive unit care (P = 0.23), severe hemorrhagic events (P = 0.13) showed no significant differences between the two groups. The patients were divided into subcohorts, and the survival rates of the leukapheresis and non-leukapheresis groups were 92.3% (95% confidence interval [CI], 77.8%-100.0%) versus 58.3% (95% CI, 38.6%-78.1%) (P = 0.03) in "sequential HL" and 76.7% (95% CI, 61.5%-91.8%) versus 54.8% (95% CI, 37.3%-72.4%) (P = 0.03) in "symptomatic HL," respectively. Moreover, in the "sequential HL" subcohort, the cumulative incidence of differentiation syndrome and following adverse events were significantly lower in the leukapheresis group.

CONCLUSIONS

In APL with "sequential HL" or "symptomatic HL" from either the disease itself or the effect of all-trans retinoic acid, therapeutic leukapheresis could be applied to reduce leukemic cell burden without significant risks.

Acute leukemia presenting as acute lower limb ischemia

Objectives: Acute lower limb ischemia (ALLI) is a common vascular emergency. However, ALLI presenting as the initial symptom of acute leukemia (AL) is scarce. Here we present a case of ALLI in the setting of acute myeloid leukemia (AML) while systematically reviewing the current literature to withdraw conclusions about the management, prognosis, and treatment for this atypical presentation of AL. Methods: We conducted a systematic electronic research according to Preferred Reporting Items for Systematic Review and Meta-Analysis protocol (PRISMA) for articles published from January 1981 up to January 2021 concerning ALLI in the setting of acute leukemia (AL). Patients' baseline characteristics were recorded and nine outcomes of interest were studied. Results: Twenty-six individuals, 16 males with a mean age of 46.3 years (±20) were included in this review. The diagnosis included 13 AML patients (50%), 11 acute promyelotic leukemia (APL) (42.3%) and two acute lymphoblastic leukemias (ALL) (7.7%). Treatment varied among nine different regimens. Four patients were treated with chemotherapy alone (15.4%), four with thrombectomy alone (15.4%), and 11 with a combination of chemotherapy and thrombectomy (42.3%). Eight major amputations were recorded (30. 8%). Thirty-day mortality was 35.7%. Forty-eight peripheral thrombotic events were recorded with 12 patients suffering recurrent thrombotic events. Conclusion: ALLI as the presenting symptom of AL is a rare condition that carries significant mortality and amputation rates. Timely diagnosis is crucial concerning short-term survival and limb salvage. APL, despite being the rarest form of AL, represented a significant proportion of the patient population in this review. The role of leukostasis in the disease's progression and the efficacy of leukapheresis as a treatment regimen should be further investigated through case-control studies.

Intracranial Hemorrhage in a Pediatric Patient with Chronic Myeloid Leukemia in Chronic Phase: A Case Report

Chronic myeloid leukemia (CML) is an uncommon entity in pediatric patients. CML in chronic phase (CML-CP) has a relatively favorable outcome. Leukostasis occurs in 9.7% of patients with CML. One of the most serious leukostasis-related complications is intracranial hemorrhage (ICH). However, this is very rare in patients with CML-CP, and few early mortalities have been reported in CML patients with leukostasis. We report the case of a 14-year-old female patient with CML-CP who developed ICH 8 days after admission. A 14-year-old girl developed symptoms of fatigue and slight fever and was diagnosed with CML-CP. She was treated with imatinib and received low-molecular-weight heparin owing to coagulation abnormalities. However, 6 days later, she developed sensorineural hearing loss, which is a symptom of leukostasis. She received hydroxyurea to reduce her white blood cell (WBC) count, and her treatment was changed from imatinib to nilotinib. The WBC and platelet counts remained unchanged, blast counts did not increase, and mild coagulation abnormality persisted. Eight days after admission, she suddenly lost consciousness and experienced respiratory arrest. Cranial computed tomography revealed multiple ICH lesions and brain hernia. She received intensive care but was diagnosed with brain death by electroencephalography and died 14 days after hospitalization. ICH is very rare in patients with CML-CP; however, patients with leukostasis and coagulation abnormalities can develop severe hemorrhage, even in the chronic phase. Thus, it is necessary to accurately estimate the cause and provide appropriate treatment for these patients.

Leukocytapheresis in Chronic Myeloid Leukemia With Leukostasis

Leukostasis in acute and chronic leukemias leads to increased cell burden and increased blood viscosity. Therapeutic leukocytapheresis is an automated procedure aimed at white blood cell depletion, and it thereby reduces the complications associated with increased blood viscosity, such as thrombotic events and mortality. In this report, we present the case of a 25-year-old patient with leukostasis and splenic laceration who was treated with therapeutic leukocytapheresis with symptomatic relief in leukostasis.

Hyperleukocytosis and Leukostasis in Acute Myeloid Leukemia: Can a Better Understanding of the Underlying Molecular Pathophysiology Lead to Novel Treatments?

Up to 18% of patients with acute myeloid leukemia (AML) present with a white blood cell (WBC) count of greater than 100,000/µL, a condition that is frequently referred to as hyperleukocytosis. Hyperleukocytosis has been associated with an adverse prognosis and a higher incidence of life-threatening complications such as leukostasis, disseminated intravascular coagulation (DIC), and tumor lysis syndrome (TLS). The molecular processes underlying hyperleukocytosis have not been fully elucidated yet. However, the interactions between leukemic blasts and endothelial cells leading to leukostasis and DIC as well as the processes in the bone marrow microenvironment leading to the massive entry of leukemic blasts into the peripheral blood are becoming increasingly understood. Leukemic blasts interact with endothelial cells via cell adhesion molecules such as various members of the selectin family which are upregulated via inflammatory cytokines released by leukemic blasts. Besides their role in the development of leukostasis, cell adhesion molecules have also been implicated in leukemic stem cell survival and chemotherapy resistance and can be therapeutically targeted with specific inhibitors such as plerixafor or GMI-1271 (uproleselan). However, in the absence of approved targeted therapies supportive treatment with the uric acid lowering agents allopurinol and rasburicase as well as aggressive intravenous fluid hydration for the treatment and prophylaxis of TLS, transfusion of blood products for the management of DIC, and cytoreduction with intensive chemotherapy, leukapheresis, or hydroxyurea remain the mainstay of therapy for AML patients with hyperleukocytosis.

Leukemoid reaction in chronic myelomonocytic leukemia patients undergoing surgery: perioperative management recommendations

CMML patients comprise an elderly and frail patient population with comorbidities that often require surgical intervention. Postsurgical leukemoid reaction, a life-threatening complication in CMML patients, may be driven by molecular mechanisms.

Treatment Outcome in Pediatric Acute Lymphoblastic Leukemia With Hyperleukocytosis in the Yeungnam Region of Korea: A Multicenter Retrospective Study

Acute lymphoblastic leukemia (ALL) with hyperleukocytosis at diagnosis is associated with early morbidity and mortality due to complications of leukostasis. Of 535 pediatric ALL patients (January 2004 to December 2016 from the Yeungnam region of Korea), 72 (13.5%) patients with an initial white blood cell (WBC) count of ≥100×10/L were included in this study, of whom 38 patients had extreme hyperleukocytosis (WBC>200×10/L) at diagnosis. Fourteen patients (19.4%) had ≥1 early respiratory and neurologic complications during induction therapy. Relapse occurred in 8 patients (24.2%) with extreme hyperleukocytosis and in 1 patient (3.0%) with an initial WBC count of 100 to 200×10/L (P=0.012). Estimated 10-year event-free survival rate (EFS) and overall survival rate were 78.3%±8.4% and 82.6%±7.7%, respectively. The 10-year EFS was significantly lower in patients with an initial WBC count of >200×10/L than in those with an initial WBC count of 100 to 200×10/L (65.7%±13.4% vs. 91.2%±7.9%; P=0.011). The 10-year EFS and overall survival rate did not differ significantly between patients with extreme hyperleukocytosis who received hematopoietic stem cell transplantation and those who received chemotherapy. In conclusion, pediatric ALL with hyperleukocytosis can lead to early complications and mortality. Patients with initial extreme hyperleukocytosis showed significantly poorer prognosis than those with WBC counts of 100 to 200×10/L.

Leukocytapheresis for patients with acute myeloid leukemia presenting with hyperleukocytosis and leukostasis: a contemporary appraisal of outcomes and benefits

Introduction: Hyperleukocytosis, defined as a total white blood cell count (WBC) >50 or more commonly >100 × 10⁹ cells/L, is a presenting feature of acute myeloid leukemia (AML) in about 6-20% of cases and is associated with a higher risk of tumor lysis syndrome (TLS), disseminated intravascular coagulation (DIC), clinical leukostasis with end organ damage, and mortality.Areas covered: In this review, authors discuss the implications of hyperleukocytosis in AML and the current understanding of cytoreductive strategies with a focus on the use of leukocytapheresis.Expert commentary: Efforts to rapidly reduce peripheral myeloblasts have included the use of leukocytapheresis. Early studies demonstrated feasibility in reducing peripheral WBC and blast counts as well as clinically relevant patient outcomes which prompted its common use for many years. However, more recent data have directly challenged the previously touted reports of reduced TLS and DIC incidence as well as survival benefit, even in patients with clinical leukostasis. The use of leukocytapheresis remains highly controversial with wide practice variations among physicians, institutions, and countries given the lack of high-quality data, risks associated with leukocytapheresis itself, associated high costs, resource utilization, and lack of evidence-based clinical guidelines.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice - Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Eighth Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating and categorizing indications for the evidence-based use of therapeutic apheresis (TA) in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Eighth Edition of the JCA Special Issue continues to maintain this methodology and rigor in order to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Eighth Edition, like its predecessor, continues to apply the category and grading system definitions in fact sheets. The general layout and concept of a fact sheet that was introduced in the Fourth Edition, has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of TA in a specific disease entity or medical condition. The Eighth Edition comprises 84 fact sheets for relevant diseases and medical conditions, with 157 graded and categorized indications and/or TA modalities. The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.

Syncope as Initial Presentation in an Undifferentiated Type Acute Myeloid Leukemia Patient with Acute Intracranial Hemorrhage

Intracranial hemorrhage (ICH) is a catastrophic complication in patients with acute myeloid leukemia (AML). AML cells, especially in the acute promyelocytic leukemia subtype, may release microparticles (MPs), tissue factor (TF), and cancer procoagulant (CP) to promote coagulopathy. Hyperfibrinolysis is also triggered via release of annexin II, t-PA, u-PA, and u-PAR. Various inflammatory cytokines from cancer cells, such as IL-1β and TNF-α, activate endothelial cells and promote leukostasis. This condition may increase the ICH risk and lead to poor clinical outcomes. Here, we present a case under a unique situation with acute ICH detected prior to the diagnosis of AML. The patient initially presented with two episodes of syncope. Rapidly progressive ICH was noted in follow-up computed tomography (CT) scans. Therefore, we highlight that AML should be among the differential diagnoses of the etiologies of ICH. Early diagnosis and timely intervention are very important for AML patients.

Therapeutic leukocytapheresis in infants and children with leukemia and hyperleukocytosis: A single institution experience

BACKGROUND

Hyperleukocytosis, defined as white blood cell (WBC) count above 100 × 10⁹ /L, has high early morbidity and mortality from leukostasis-related complications, namely intracranial hemorrhage and pulmonary distress. Initiating chemotherapy without prior leukocytoreduction may lead to tumor lysis syndrome (TLS). Therapeutic leukocytapheresis (TL) is used as one leukocytoreductive intervention; however, its safety and efficacy in pediatric leukemia has not been established. The purpose of this study is to evaluate safety of TL in pediatric patients and assess the efficacy of TL in reducing WBC count in pediatric leukemia.

METHODS

Retrospective chart review was conducted on 14 patients with acute lymphoblastic leukemia (ALL) and 5 with acute myeloid leukemia (AML) who underwent TL during the period 2000-2014 at a single institution.

RESULTS

Mean WBC count of 19 patients who received TL was 483.2 × 10⁹ /L (547.1 in ALL, 304.3 in AML); a portion of patients presented with central nervous system symptoms (15%), respiratory symptoms (10%), or both (10%). TL reduced WBC count (mean 50.7% reduction after a single TL procedure; additional 17.1% reduction after a second TL procedure in 6 patients). Short-term survival immediately following TL was 100% without any major procedural complication. Mean survival time in patients with AML was 1.5 years and with ALL was 6.5 years.

CONCLUSIONS

TL significantly reduces WBC number in pediatric leukemia patients as young as 22 days old. In our retrospective study, TL was not associated with any significant complications and suggests that TL is a safe initial procedure in pediatric leukemia.

Comparing leukapheresis protocols for an AML patient with symptomatic leukostasis

BACKGROUND

Acute myeloid leukemia (AML) is a malignancy characterized by rapid clonal proliferation of myeloid precursors, which can result in hyperleukocytosis. Leukapheresis can be used to rapidly reduce the white blood cell count (WBC). However, the only FDA cleared device for WBC depletion, the COBE Spectra, will no longer be supported by the manufacturer in 2017, and there are few studies comparing different methods of leukapheresis.

CASE REPORT

A 68-year-old African American female was admitted to the hospital for relapse of her AML. Laboratory data demonstrated a WBC count of 291 600/μL and flow cytometry of the peripheral blood demonstrated 85% myeloid blasts. Leukapheresis was ordered to help treat the leukostasis.

METHODS

Three different apheresis protocols were used to achieve cytoreduction: Spectra Optia mononuclear collection (MNC) protocol, Spectra Optia granulocyte collection (PMN) protocol, and Therakos CELLEX buffy coat collection without return. Due to different inlet flow rates, the procedures were evaluated based on the number of WBCs collected and volume of blood processed (VBP).

RESULTS

The Spectra Optia PMN collected the most WBCs and collected nearly as many WBCs per VBP as the Therakos CELLEX, which had the highest value.

CONCLUSION

To our knowledge, we are reporting the first use of Therakos CELLEX and Spectra Optia PMN protocol for WBC depletion. While the Spectra Optia granulocyte protocol showed the best performance for this AML patient, further studies will be needed to compare the Spectra Optia PMN protocol to the MNC protocol for AML patients.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice-Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Seventh Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating, and categorizing indications for the evidence-based use of therapeutic apheresis in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the Committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Seventh Edition of the JCA Special Issue continues to maintain this methodology and rigor to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Seventh Edition, like its predecessor, has consistently applied the category and grading system definitions in the fact sheets. The general layout and concept of a fact sheet that was used since the fourth edition has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis in a specific disease entity. The Seventh Edition discusses 87 fact sheets (14 new fact sheets since the Sixth Edition) for therapeutic apheresis diseases and medical conditions, with 179 indications, which are separately graded and categorized within the listed fact sheets. Several diseases that are Category IV which have been described in detail in previous editions and do not have significant new evidence since the last publication are summarized in a separate table. The Seventh Edition of the JCA Special Issue serves as a key resource that guides the utilization of therapeutic apheresis in the treatment of human disease. J. Clin. Apheresis 31:149-162, 2016. © 2016 Wiley Periodicals, Inc.

Chest radiographic and CT findings in hyperleukocytic acute myeloid leukemia: A retrospective cohort study of 73 patients

Hyperleukocytic acute myeloid leukemia (AML) is associated with pulmonary complications and high early mortality rate, but given its rarity, data on chest radiographic presentation are scarce.We retrospectively reviewed the charts of 73 AML patients admitted with white blood cell count >100 × 10/L between 2003 and 2014 in order to describe the chest radiographic and computed tomography (CT) findings and to correlate them with AML subtype and respiratory symptoms.Forty-two of the 73 patients (58%) overall and 36 of the 54 patients (67%) with clinical signs of pulmonary leukostasis had abnormal radiographs on admission. The presence of radiographic abnormalities was significantly associated with dyspnea and oxygen/ventilatory support requirements (P < 0.01) and with day 28 mortality (45% vs 13%, P = 0.005) but not with monocytic subtype of AML. Sixteen patients had isolated focal basilar airspace opacities, unilateral (n = 13) or bilateral (n = 3), while 16 patients had bilateral diffuse opacities, interstitial (n = 12) or airspace and interstitial (n = 4). Two patients had isolated pleural effusion, 2 patients had unilateral midlung airspace opacities, and 6 patients had a combination of focal airspace and diffuse interstitial opacities. Overall, 2 patterns accounted for 75% of abnormal findings: bilateral diffuse opacities tended to be associated with monocytic AML, whereas basilar focal airspace opacities were more frequent in nonmonocytic AML (P < 0.05). Eighteen patients had CT scans, revealing interlobular septal thickening (n = 12), airspace (n = 11) and ground-glass (n = 9) opacities, pleural effusions (n = 12), and acute pulmonary embolism (n = 2).Hyperleukocytic AML is frequently associated with abnormal chest radiographs, involving mostly focal basilar airspace opacities (more frequent in nonmonocytic AML) or diffuse bilateral opacities. CT scan should be considered broadly due to the suboptimal resolution of radiographs for detecting signs of leukostasis.

Leukostasis in adult acute hyperleukocytic leukemia: a clinician's digest

Leukostasis is a poorly understood and life-threatening complication of acute hyperleukocytic leukemia. The incidence of hyperleukocytosis and leukostasis differs among various subtypes of leukemias. While the pathophysiology of leukostasis is not fully understood, recent research has elucidated many novel pathways that may have therapeutic implications in the future. Respiratory and neurological compromise represents the classical clinical manifestations of leukostasis. If it is not diagnosed and treated rapidly, the one-week mortality rate is approximately 40%. Targeted induction chemotherapy is an important component of the successful treatment of leukostasis, although other modalities of cytoreduction are being used and investigated. Copyright © 2016 John Wiley & Sons, Ltd.

Early Complications of Hyperleukocytosis and Leukapheresis in Childhood Acute Leukemias

Hyperleukocytosis in children with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) is associated with early morbidity and mortality. The benefit from leukapheresis is controversial, and its complications are not well defined. We analyzed the frequency of early complications in children with ALL and AML presenting with white blood cell (WBC) count >100 × 10(9)/L, and the type and frequency of complications related to leukapheresis. During a 12-year period, 84 of 634 (13%) ALL and 18 of 143 (12.5%) AML patients presented with hyperleukocytosis. Leukapheresis was performed in 18 ALL and 12 AML patients. The median initial WBC was 474 × 10(9)/L in the leukapheresis group compared with 175 × 10(9)/L in the nonleukapheresis group. Neurological leukostasis occurred in 6 ALL (7.1%) and 4 AML (22.2%) patients. Pulmonary leukostasis occurred in 16 ALL (19%) and 4 AML patients (22.2%). Neurological symptoms improved in few patients after leukapheresis, except in patients with very high WBC (>650 × 10(9)/L in ALL and >400 × 10(9)/L in AML). Leukapheresis improved respiratory symptoms in some patients but caused worsening symptoms in others. Early death was associated with neurological complications, AML diagnosis, and coagulopathy. Leukapheresis did not delay initiation of chemotherapy, nor did it impact early response to chemotherapy or long-term survival. Complications included femoral vein thrombosis, electrolyte imbalances, and hemodynamic instability, which were all reversible. The role of leukapheresis as a cytoreductive procedure in childhood hyperleukocytic leukemia remains to be well defined.

Leukostasis in Children and Adolescents with Chronic Myeloid Leukemia: Japanese Pediatric Leukemia/Lymphoma Study Group

BACKGROUND

The details of leukostasis in children and adolescents with chronic myeloid leukemia (CML) are unknown. This study determined the characteristics of leukostasis in children and adolescents with CML.

PROCEDURE

A total of 256 cases from a retrospective study of patients with CML conducted by the Japanese Pediatric Leukemia/Lymphoma Study Group from 1996 to 2011 were analyzed, and of these, 238 cases were evaluated in this study.

RESULTS

Leukostasis was diagnosed in 23 patients (9.7%). The median leukocyte count and spleen size below the left costal margin in cases with leukostasis were significantly higher and larger when compared to those in cases without leukostasis (458.5 × 10(9) /l vs. 151.8 × 10(9) /l (P < 0.01), and 13 vs. 5 cm (P < 0.01), respectively). Leukostasis occurred with ocular symptoms in 14 cases, priapism in four cases, and dyspnea, syncope, headache, knee pain, difficulty hearing, and aseptic necrosis of the femoral head in one case each. One case had two leukostasis symptoms simultaneously. Three cases were diagnosed before imatinib became available. Five cases received special treatment, and in the remaining 15 cases, all of these symptoms resolved after treatment with imatinib.

CONCLUSIONS

This retrospective study represents the largest series of children and adolescents in which leukostasis of CML has been reported. Our data provide useful insight into the characteristics of leukostasis in recent cases of children and adolescents with CML.

Pre-treatment with oral hydroxyurea prior to intensive chemotherapy improves early survival of patients with high hyperleukocytosis in acute myeloid leukemia

Acute myeloid leukemia with high white blood cell count (WBC) is a medical emergency. A reduction of tumor burden with hydroxyurea may prevent life-threatening complications induced by straight chemotherapy. To evaluate this strategy, we reviewed medical charts of adult patients admitted to our institution from 1997 to 2011 with non-promyelocytic AML and WBC over 50 G/L. One hundred and sixty patients were included with a median WBC of 120 G/L (range 50-450), 107 patients received hydroxyurea prior to chemotherapy, and 53 received emergency induction chemotherapy (CT). Hospital mortality was lower for patients treated with hydroxyurea (34% versus 19%, p = 0.047) even after adjusting for age (p < 0.01) and initial WBC count (p = 0.02). No evidence of any difference between treatment groups in terms of WBC decline kinetics and disease free survival (p = 0.87) was found. Oral hydroxyurea prior to chemotherapy seems a safe and efficient strategy to reduce early death of hyperleukocytic AML patients.

Therapeutic leukocytapheresis for improvement in respiratory function in a woman with hyperleukocytosis and mantle cell lymphoma with a circulating small lymphocyte phenotype

Mantle cell lymphoma is an aggressive malignant B-cell disorder that often presents with a leukemic picture. Circulating lymphoma cell morphology may vary from small round mature-appearing lymphocytes resembling the lymphocytes of chronic lymphocytic leukemia to large prolymphocytoid or blastoid cells. Rare reports of hyperleukocytosis with leukostasis, treated with leukocytapheresis, are described in patients with prolymphocytoid or blastoid morphology. We report an 88 year old woman with mantle cell lymphoma, hyperleukocytosis (WBC > 400 × 10(3) /µL) with severe respiratory compromise but without interstitial or alveolar infiltrates on radiograph or computerized tomography of the chest. She was afebrile and had no central nervous system signs. Circulating lymphoma cell morphology was predominantly of the small lymphocyte type. A two-whole-blood-volume leukocytapheresis reduced her WBC from 465 to 221 × 10(3) /µL in 150 min. Her respiratory rate decreased from 28/min to 18/min and her arterial oxygen saturation (SpO2 ) rose from 91% to 97% on 6 L/min of oxygen by nasal cannula. Severe breathlessness before the procedure abated completely by the end of the procedure. Respiratory compromise may occur in mantle cell lymphoma with hyperleukocytosis with a mature lymphoma cell phenotype, even without a clear picture of leukostasis. Although the ultimate survival of the patient depends on treatment with chemotherapy, leukocytapheresis for alleviation of symptoms may be warranted and should be considered. Respiratory status and response to leukocytapheresis should be documented with physiological measurements. J. Clin. Apheresis 31:398-402, 2016. © 2015 Wiley Periodicals, Inc.

Physiological measurements corroborate symptomatic improvement after therapeutic leukapheresis in a pregnant woman with chronic myelogenous leukemia

Therapeutic leukapheresis can control the white blood cell count (WBC) of pregnant women with chronic myelogenous leukemia (CML) who have hyperleukocytosis without leukostasis. The medical justification for this treatment has not been objectively documented. We report a 27-year-old woman, diagnosed with CML at 10-week gestation, who developed severe dyspnea on exertion. A workup that included chest CT and echocardiography with a bubble study detected no cardiopulmonary pathology to explain her symptoms, and thus she was referred for leukapheresis. Prior to her first leukapheresis, which lowered her WBC from 154 × 10(3) /μL to 133 × 10(3) /μL, her oxygen saturation (SpO2 ) on room air decreased from 98 to 93% during 100 feet of slow ambulation and she was dyspneic. Just after the leukapheresis, her dyspnea on exertion was much improved and her SpO2 remained at 98% with repeat ambulation. Spirometry and lung volume studies obtained before and after her first leukapheresis demonstrated 32 and 31% improvements in forced vital capacity and forced expiratory volume in 1 s respectively, a 25% increase in functional residual capacity, and a 142% improvement in expiratory reserve volume. Residual volume decreased by almost 20%. Three times in a week, leukapheresis was continued until her WBC was controlled with interferon α-2b approximately 4 weeks later. Her dyspnea had completely resolved. She gave birth by elective caesarean section to a healthy boy at 32 weeks. Corroboration of symptom relief by leukapheresis with physiological data may justify such treatment in pregnant patients with CML. J. Clin. Apheresis 31:393-397, 2016. © 2015 Wiley Periodicals, Inc.

How I treat hyperleukocytosis in acute myeloid leukemia

Hyperleukocytosis (HL) per se is a laboratory abnormality, commonly defined by a white blood cell count >100 000/µL, caused by leukemic cell proliferation. Not the high blood count itself, but complications such as leukostasis, tumor lysis syndrome, and disseminated intravascular coagulation put the patient at risk and require therapeutic intervention. The risk of complications is higher in acute than in chronic leukemias, and particularly leukostasis occurs more often in acute myeloid leukemia (AML) for several reasons. Only a small proportion of AML patients present with HL, but these patients have a particularly dismal prognosis because of (1) a higher risk of early death resulting from HL complications; and (2) a higher probability of relapse and death in the long run. Whereas initial high blood counts and high lactate dehydrogenase as an indicator for high proliferation are part of prognostic scores guiding risk-adapted consolidation strategies, HL at initial diagnosis must be considered a hematologic emergency and requires rapid action of the admitting physician in order to prevent early death.

Leukocytapheresis for the treatment of hyperleukocytosis secondary to acute leukemia

Patients presenting with new or recurrent acute leukemia, particularly of the myeloid lineage, with WBC counts exceeding 100 × 109/L are often considered for leukocytapheresis, especially if they are experiencing symptoms of leukostasis. These symptoms are thought to occur because of blast aggregates and WBC thrombi in the circulation, which reduce blood flow. Leukostasis may cause various complications, including hyperviscosity syndrome, vascular occlusion resulting in intracranial hemorrhages and respiratory failure, and perivascular leukemic infiltrates. Leukostasis occurs more commonly with a high WBC count and with leukemias of monocytoid lineage such as acute myelomonocytic leukemia, which is a reflection of the nature of the leukemic blasts. Leukocytapheresis is used in an effort to quickly decrease a patient's circulating blast count, which can both prevent the development of leukostasis and provide symptomatic relief of leukostasis. However, the impact of leukocytapheresis on early- and long-term mortality is controversial, with several studies producing conflicting results. In this chapter, the pathophysiology of leukostasis, performance of leukocytapheresis, and efficacy of this treatment are reviewed.

Leukapheresis in childhood acute leukemias: single-center experience

Hyperleukocytosis in patients with leukemia is associated with early mortality, especially due to the pulmonary and neurological complications of leukostasis. The prompt use of leukapheresis may improve patients' survival in the initial treatment period. The medical records of all previously untreated acute leukemia patients were reviewed to determine whether there was hyperleukocytosis at presentation. This study summarizes a single-center experience of leukapheresis that was applied to 12 children with acute leukemia and hyperleukocytosis. The median leukocyte count at diagnosis was 589,000/mm(3) (range: 389,000-942,000/mm(3)) for ALL patients and 232,000/mm(3) (range: 200,000-282,000/mm(3)) for AML patients. A central venous catheter (CVC) was inserted, and leukapheresis procedures were repeated at 12-hour intervals. A total of 29 leukapheresis cycles were performed on 12 children. The median number of cycles of leukapheresis required by each patient was two (range: 1-4). The median absolute and percentage reductions in white blood cell (WBC) count after the first cycle of leukapheresis were 113,000/mm(3) (range: 55,000-442,000/mm(3)) and 36% (range: 16-57.4%), respectively. As a laboratory finding, mild hypocalcemia was the most frequently observed complication. No patients developed any other problem related to the procedure. Our results showed that leukapheresis is a safe and effective procedure if performed by experienced staff.

Management of Acute Myeloid Leukemia in the Intensive Care Setting

Patients with acute myeloid leukemia (AML) who are newly diagnosed or relapsed and those who are receiving cytotoxic chemotherapy are predisposed to conditions such as sepsis due to bacterial and fungal infections, coagulopathies, hemorrhage, metabolic abnormalities, and respiratory and renal failure. These conditions are common reasons for patients with AML to be managed in the intensive care unit (ICU). For patients with AML in the ICU, providers need to be aware of common problems and how to manage them. Understanding the pathophysiology of complications and the recent advances in risk stratification as well as newer therapy for AML are relevant to the critical care provider.

[Leukostasis and tumor lysis: important complications of hyperleukocytosis]

The occurrence of hyperleukocytosis (leukocytes > 100.000/μl) is associated with complications such as leukostasis, tumor lysis and consumption coagulopathy in patients with acute leukemia much more often than in patients with chronic malignant hematological diseases. To manage these situations may be complex as organ failure is often imminent or manifest, infectious complications arise and indications for induction chemotherapy are usually urgent. Prophylaxis and therapy of the tumor lysis syndrome consists of hydration, lowering of uric acid and the management of electrolyte disturbances. Leukostasis requires immediate reduction of the leukocyte count by leukapheresis, administration of hydroxycarbamide and, ultimately, by causative and specific treatment of the underlying disease itself. In patients with curable diseases or favorable long-term prognosis, transfer to the intensive care unit must be evaluated early in the course of impending organ dysfunction, especially in cases of acute respiratory failure.

Cranial irradiation in adults diagnosed with acute myelogenous leukemia presenting with hyperleukocytosis and neurologic dysfunction

This study describes our institution's experience using whole brain radiation therapy (WBRT) to treat patients with acute myelogenous leukemia (AML) presenting with hyperleukocytosis. After approval by the institutional review board, we identified patients with AML and hyperleukocytosis using hospital records. The primary endpoints in the study included alleviation of neurological symptoms (or prevention if prophylactic RT was used), overall survival, development of intracranial hemorrhage (ICH) and ≥ grade 3 toxicities using the Common Terminology Criteria for Adverse Events version 4.0 (CTCAE v4.0). Eighteen patients received WBRT for the treatment of AML hyperleukocytosis. Thirteen patients received treatment in order to control neurological symptoms. Clinical assessment showed that 12 of 13 patients (92%) achieved resolution of neurological symptoms either concurrent with RT or immediately after RT. The mean overall survival for all of the patients who received WBRT was 14.2 months (95% confidence interval, 5.4-23.0). No patient who received RT experienced ≥ grade 3 toxicity. Two (6%) patients developed ICH following therapy. Our institution's experience demonstrates that WBRT may be utilized as part of multimodality therapy in order to alleviate or prevent neurological symptoms in patients with AML presenting with leukostasis.

Leukocyte Depletion by Therapeutic Leukocytapheresis in Patients with Leukemia

Hyperleukocytosis is a complication of various leukemias and can result in life-threatening leukostasis. Critical white blood cell (WBC) counts are conventionally defined as higher than 100 × 10(9)/l in acute myeloid leukemia and > 300 × 10(9)/l in acute lymphatic leukemia and other leukemic disorders (e. g. chronic myeloid leukemia). Leukocytapheresis is a therapeutic tool to reduce leukocyte counts in patients with symptomatic or threatening leukostasis until induction chemotherapy works. In patients with temporary contraindications against cytotoxic drugs, e.g. during pregnancy, leukocytapheresis can be used as a bridging therapy until conventional chemotherapy can be started. Therapeutic leukocytapheresis should be performed in specialized centers by experienced, well-trained staff. Thorough monitoring of the patients is extremely relevant. During a single procedure, WBC count can be reduced by 10-70%. Treatment should be repeated daily and can be discontinued when the symptoms of leukostasis have been resolved and/or leukocyte counts have fallen below the critical thresholds. There are no prospective studies evaluating the clinical efficacy of therapeutic leukocytapheresis in patients with hyperleukocytosis. It can be concluded from retrospective studies that leukocytapheresis might have some beneficial effect in early morbidity and mortality of patients with newly diagnosed AML but has no influence on overall long-term survival. Induction chemotherapy is the most important treatment in these patients and must never be postponed.

Hyperleukocytosis, leukostasis and leukapheresis: practice management

Hyperleukocytosis, arbitrarily defined in acute leukemia as a white blood cell count greater than 100,000/mL, often is associated with increased morbidity and mortality in patients with leukemic processes. It can induce leukostasis, tumor lysis syndrome and disseminated intravascular coagulopathy and has significant prognostic implications with or without one of these clinical complications. The main sites that tend to be injured from the obstructions are the central nerve system and lungs. Despite characteristic clinical presentations, the diagnosis of leukostasis is rarely made with high confidence. The main goal of the management of hyperleukocytosis and/or leukostasis is to reduce the white blood cell count before starting induction chemotherapy. The cytoreduction can be achieved by either leukapheresis and/or hyroxyurea. The technical aspects, complications and efficacy of leukapheresis are discussed in the current article.

Why does my patient have leukocytosis?

Leukocytosis is one of the most common laboratory abnormalities in medicine, and one of the most frequent reasons for hematologic consultation. Effective evaluation of leukocytosis requires an attentive history, careful physical examination, meticulous review of the complete blood count and peripheral blood smear, judicious application of laboratory and radiologic testing, and thoughtful analysis. Definitive diagnosis may require bone marrow aspiration and biopsy, imaging studies, and specialized molecular tests. The differential diagnosis of leukocytosis includes physiologic responses to a broad range of infectious and inflammatory processes, as well as numerous primary hematologic disorders such as leukemias, lymphomas, and myeloproliferative neoplasms.

Multiple compartment syndrome in a pediatric patient with CML

Compartment syndrome is a limb-threatening and life-threatening emergency resulting from elevated intracompartmental pressure. Prompt surgical intervention and treatment are necessary to prevent irreparable damage to muscle and nerve tissues. Leukemic infiltration of the muscle is an unusual cause of compartment syndrome and has been documented to occur secondary to hyperleukocytic leukemias, most commonly in acute myeloid leukemia. We present a rare case of multiple compartment syndrome in the buttock and thigh of an 11-year-old male patient with chronic myelomonocytic leukemia. The diagnosis of acute compartment syndrome was delayed, causing irreversible tissue damage. Physicians are generally unfamiliar with leukemia-induced complications and may not initially suspect leukemic compartment syndrome because of its rarity. Awareness of its clinical features is critical, because early diagnosis and prompt surgical debridement can prevent significant morbidity and even death.

Guidelines on the use of therapeutic apheresis in clinical practice--evidence-based approach from the Apheresis Applications Committee of the American Society for Apheresis

The American Society for Apheresis (ASFA) Apheresis Applications Committee is charged with a review and categorization of indications for therapeutic apheresis. Beginning with the 2007 ASFA Special Issue (fourth edition), the subcommittee has incorporated systematic review and evidence-based approach in the grading and categorization of indications. This Fifth ASFA Special Issue has further improved the process of using evidence-based medicine in the recommendations by refining the category definitions and by adding a grade of recommendation based on widely accepted GRADE system. The concept of a fact sheet was introduced in the Fourth edition and is only slightly modified in this current edition. The fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis. The article consists of 59 fact sheets devoted to each disease entity currently categorized by the ASFA as category I through III. Category IV indications are also listed.