Isolated myelosarcoma in children--update and review

Myeloid sarcoma with RBM15::MRTFA (MKL1) mimicking vascular neoplasm

Extramedullary involvement of acute myeloid leukemia (AML), aka myeloid sarcoma, is a rare phenomenon in acute megakaryoblastic leukemia with RBM15:: MRTFA(MKL1) fusion, which might mimic non-hematologic malignancies. A 7-month-old infant presented with leukocytosis, hepatosplenomegaly, multiple lymphadenopathies, and a solid mass in the right thigh. Initially, the patient was diagnosed with a malignant vascular tumor regarding the expression of vascular markers from the biopsy of the right thigh lesion that was performed after the inconclusive bone marrow biopsy. The second bone marrow biopsy, which was performed due to the partial response to sarcoma treatment, showed hypercellular bone marrow with CD34 and CD61-positive spindle cell infiltration and > 20% basophilic blasts with cytoplasmic blebs. RNA sequencing of soft tissue biopsy revealed the presence of RBM15::MRTFA(MKL1) fusion. Based on these findings, myeloid sarcoma/AML with RBM15::MRTFA(MKL1) fusion diagnosis was made. AML with RBM15::MRTFA(MKL1) fusion can initially present as extramedullary lesions and might cause misdiagnosis of non-hematologic malignancies.

Isolated meningeal myeloid sarcoma with recurrent MLL-AF6 translocation: a case report

This study aimed to help improve the diagnosis and treatment of isolated myeloid sarcoma. We report the case of a female adolescent patient with isolated meningeal myeloid sarcoma. She was admitted to our department because of vomiting, headache and hearing loss. Positron emission tomography-computed tomography and brain magnetic resonance imaging showed multiple intracranial space-occupying lesions. A complete examination, including morphology, cytology, immunophenotyping, cytogenetics and molecular biology tests of cerebrospinal fluid and bone marrow, was conducted. The diagnosis of primary myeloid sarcoma of the central nervous system with mixed lineage leukemia gene rearrangement with AF6 was established. The patient underwent systemic chemotherapy and intrathecal treatment followed by whole-brain radiotherapy. She achieved complete remission for 84 months and has not developed bone marrow involvement during follow-up. The combination of morphology, cytology, flow cytometry, cytogenetics and molecular analysis can improve the definite diagnosis of isolated myeloid sarcoma.

Clinical Characteristics and Treatment Outcomes of Myeloid Sarcoma in Children: The Experience of the Polish Pediatric Leukemia and Lymphoma Study Group

Introduction

Myeloid sarcoma (MS) is an extramedullary malignant tumor composed of immature myeloid cells. It occurs in patients with acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), or chronic myeloid leukemia (CML). MS may coincide with disease diagnosis or precede bone marrow involvement by months or even years; it can also represent the extramedullary manifestation of a relapse (1, 2).

Aim

The aim of this study is to describe clinical characteristics of children diagnosed with MS in Poland as well as to analyze diagnostic methods, treatment, and outcomes including overall survival (OS), relapse-free survival (RFS), and event-free survival (EFS). The study also attempted to identify factors determining treatment outcomes.

Patients

The study group comprised 43 patients (F=18, M=25) aged 0-18 years (median age, 10.0 years; mean age, 8.8 years) diagnosed with MS based on tumor biopsy and immunohistochemistry or identification of underlying bone marrow disease and extramedullary tumor according to imaging findings.

Methods

The clinical data and diagnostic and therapeutic methods used in the study group were analyzed. A statistical analysis of the treatment outcomes was conducted with STATISTICA v. 13 (StatSoft, Inc., Tulsa, OK, USA) and analysis of survival curves was conducted with MedCalc 11.5.1 (MedCalc Software, Ostend, Belgium). Statistical significance was considered at p<0.05.

Results

In the study group, MS was most frequently accompanied by AML. The most common site of involvement was skin, followed by orbital region. Skin manifestation of MS was more common in the age group <10 years. The most frequent genetic abnormality was the t(8;21)(q22;q22) translocation. The 5-year OS probability (pOS), 5-year RFS probability (pRFS), and 5-year EFS probability (pEFS) were 0.67 ± 0.08, 0.79 ± 0.07, and 0.65 ± 0.08, respectively. In patients with isolated MS and those with concurrent bone marrow involvement by AML/MDS, pOS values were 0.56 ± 0.12 and 0.84 ± 0.09 (p=0.0251), respectively, and pEFS values were 0.56 ± 0.12 and 0.82 ± 0.08 (p=0.0247), respectively. In patients with and without the t(8;21)(q22;q22) translocation, pEFS values were 0.90 ± 0.09 and 0.51 ± 0.14 (p=0.0490), respectively.

Conclusions

MS is a disease with a highly variable clinical course. Worse treatment outcomes were observed in patients with isolated MS compared to those with concurrent bone marrow involvement by AML/MDS. Patients with the t(8;21)(q22;q22) translocation were found to have significantly higher pEFS. MS location, age group, chemotherapy regimen, surgery, and/or radiotherapy did not have a significant influence on treatment outcomes. Further exploration of prognostic factors in children with MS is indicated.

A rare PALB2 germline variant causing G2/M cell cycle arrest is associated with isolated myelosarcoma in infancy

BACKGROUND

Isolated myelosarcoma of infancy is a rare presentation of acute myelogenous leukaemia (AML). Because of its rarity and early onset in infancy underlying genetic predisposition is potentially relevant in disease initiation.

METHODS AND RESULTS

We report an oncologic emergency in an infant with thoracic and intraspinal aleukaemic myeloid sarcoma causing acute myelon compression and lower leg palsy. Whole-exome sequencing of the patient's germline DNA identified a rare PALB2 (OMIM 610355) variant (p.A1079S), which is located in a domain critical for the gene's proper function within the homology-directed repair pathway. In line with potential DNA damage repair defects mediated by the PALB2 deregulation, the patient's fibroblasts showed increased sensitivity towards radiation and DNA intercalating agents.

CONCLUSION

Therefore, we suggest PALB2 p.A1079S as a pathogenic variant potentially contributing to the here observed patient phenotype.

Myeloid Sarcoma of the Testis in Children: Clinicopathologic and Immunohistochemical Characteristics With KMT2A (MLL) Gene Rearrangement Correlation

Myeloid sarcoma (MS) is defined as an extramedullary mass-forming lesion composed of immature myeloid cells. It is a rare but well-known manifestation of acute myeloid leukemia. Pediatrics testicular MS may pose a possible diagnostic challenge, an issue that is underscored in the few testicular pediatric MS cases reported in the literature. Herein, we report a series of 5 cases of pediatric testicular MS that are evaluated at the morphologic and immunohistochemical levels with correlation with the KMT2A (MLL) rearrangement status. Three patients presented with no prior history of acute myeloid leukemia. All 5 cases showed monoblastic morphology; positive for CD33, CD43, CD68, CD163, CD4 (dim), and lysozyme; and negative for CD10, CD34, CD117, and myeloperoxidase. KMT2A (MLL) rearrangement was detected in 4 of the 5 cases. In the literature, 8 more cases of pediatric testicular lymphoma were reported. Most of them showed monocytic differentiation and KMT2A (MLL) rearrangement was reported in 3 of the cases. In conclusions, testicular MS in pediatric patients shows monoblastic differentiation which may be attributed to the KMT2A (MLL) rearrangement. We also highlight the importance of using an extended immunohistochemistry panel in the diagnosis of MS.

Diagnostic and Therapeutic Considerations for Extramedullary Leukemia

PURPOSE OF REVIEW

The purpose of this review is to summarize the current literature on the presentation, diagnosis, and treatment options available for extramedullary (EM) manifestations of leukemia including myeloid sarcoma (MS) and leukemia cutis (LC).

RECENT FINDINGS

Advanced imaging using 18FDG-PET/CT is an effective screening tool for EM manifestations of leukemia. The role of radiation therapy has been more clearly delineated in the treatment of both MS and LC. FDA-approved targeted agents have improved outcomes in patients with AML but have not demonstrated improvements specifically for EM; however, a checkpoint inhibitor, Ipilimumab, holds promise in impacting local control for the treatment of AML-related EM. EM manifestations of leukemia pose significant therapeutic challenges. Treatment of EM is predicated on multiple factors including the presence of concomitant bone marrow involvement, AML-risk classification, and timing of presentation at initial diagnosis or relapse following systemic therapy.

Pediatric myeloid sarcoma: a single institution clinicopathologic and molecular analysis

Myeloid sarcoma (MS) is a neoplastic condition composed of immature myeloid cells involving an extramedullary site. We investigated underlying chromosomal and molecular alterations to assess potential molecular markers of prognosis and outcome in this rare pediatric disease. We conducted a retrospective review of clinicopathologic and cytogenetic data from 33 pediatric patients with MS (ages 1 month-18 years) at our institution over a 32 year period (1984-2016). Tissue-based cancer microarray and targeted next-generation sequencing analysis were performed on six cases. The median age at diagnosis was 2.8 years with a male-to-female ratio of 2.6:1. MS is commonly presented with concomitant marrow involvement (n = 12, 36.4%) or as a recurrence of acute myeloid leukemia (AML; n = 14, 42.4%). The skin (n = 18, 54.5%) and soft tissue (n = 9, 27.3%) were the most common sites of involvement. Twenty-one of 25 samples (84.0%) harbored chromosomal aberrations; KMT2A alterations (n = 10, 40.0%) or complex cytogenetics (n = 7, 28.0%) were most frequent. Mutations in RAS, tyrosine kinase, cell signaling, and chromatin remodeling genes were detected. When compared to pediatric patients with AML without extramedullary involvement (EMI), inferior overall survival (OS) was observed (18.8 months vs. 89.3 months, p = .008). Pediatric patients with MS with non-favorable cytogenetics [abnormalities other than t(8;21), inv(16)/t(16;16), or t(15;17)] had a significantly lower OS compared to patients with AML with non-favorable cytogenetics and no extramedullary involvement (8.0 months vs. 28.1 months, p < .001). Pediatric MS is a rare disease with diverse clinical presentations. Non-favorable cytogenetics may be a poor prognostic marker for pediatric patients with MS and molecular diagnostics can assist with risk stratification and identify potentially actionable targets.

Myeloid Sarcoma: Presentation, Diagnosis, and Treatment

Myeloid sarcoma is an extramedullary tumor of immature granulocytic cells. It is a rare condition, most often associated with acute myeloid leukemia (AML), although in some rare cases it may present in nonleukemic patients. It should therefore be considered as a differential diagnosis of any atypical cellular infiltrate. It may occur at any site, leading to very varied clinical presentations. Diagnosis is challenging and relies on a high index of suspicion as well as radiology, histology, immunophenotyping, and molecular analyses, which also are essential for risk stratification and treatment planning. Systemic chemotherapy using AML-like regimens should be commenced early, even in nonleukemic disease. Surgery and/or radiotherapy may be indicated for symptomatic lesions or tumors causing local organ dysfunction or obstruction. Allogeneic hematopoietic stem cell transplantation has demonstrated promising results, particularly in patients who achieved complete remission with AML-induction protocols, and recent advances in genetic profiling may enable the development of novel targeted therapies. Prospective multicenter controlled trials are required to further refine management decisions and investigate the role of novel targeted therapies.

Unusual cause for testicular swelling in a child

Myeloid sarcoma is a rare solid tumour composed of primitive precursors of granulocytic series of white blood cells involving extramedullary anatomic site. Here we report the case of a 10-month-old with testicular swelling, who was finally diagnosed with granulocytic sarcoma. This case demonstrates that Granulocytic sarcoma should be considered as a part of the differential diagnosis for testicular swelling in spite of having normal peripheral counts and absence of hepatosplenomegaly.

Transient spontaneous remission in congenital MLL-AF10 rearranged acute myeloid leukemia presenting with cardiorespiratory failure and meconium ileus

Background

Neonatal leukemia is a rare disease with an estimated prevalence of about one to five in a million neonates. The majority being acute myeloid leukemia (AML), neonatal leukemia can present with a variety of symptoms including hyperleucocytosis, cytopenia, hepatosplenomegaly, and skin infiltrates. Chromosomal rearrangements including mixed lineage leukemia (MLL) translocations are common in neonatal AML.

Case presentation

A female neonate born at 34 weeks gestation presented with cardiorespiratory failure, hepatosplenomegaly, pancytopenia, and coagulopathy. She required intensive care treatment including mechanical ventilation, high-dose catecholamine therapy, and multiple transfusions. Small intestinal biopsy obtained during laparotomy for meconium ileus revealed an infiltrate by an undifferentiated monoblastic, MLL-rearranged leukemia. No other manifestations of leukemia could be detected. After spontaneous clinical remission, lasting 5 months without any specific treatment, the patient presented with leukemia cutis and full-blown monoblastic leukemia. MLL-AF10-rearranged AML could be re-diagnosed and successfully treated with chemotherapy and hematopoietic stem cell transplantation.

Conclusions

Our patient exhibited a unique manifestation of neonatal MLL-AF10 rearranged AML with cardiorespiratory failure and intestinal infiltration. It highlights the importance of leukemia in the differential diagnosis of neonatal distress, congenital hematological abnormalities, and skin lesions.

Do Not Forget the Glycophorin A: An Unusual Case of Myeloid Sarcoma

Acute erythroid leukemia is rare, with isolated reports on presentation as an extramedullary tumor mass (myeloid sarcoma). We describe a case of pure erythroid leukemia presenting as an orbital mass in a 1-year, 9-month-old girl. This is only the second case described in a child. Tissue biopsy of the tumor mass showed medium-sized cells that were glycophorin A positive and negative with conventional myeloid markers. Flow cytometry, bone marrow aspirate, and trephine confirmed the diagnosis of pure erythroid leukemia.

Progress and Prospects in Pediatric Leukemia

Pediatric leukemia is the single most common malignancy affecting children, representing up to 30% of all pediatric cancers. Dramatic improvements in survival for acute lymphoblastic leukemia (ALL) have taken place over the past 4 decades with outcomes approaching 90% in the latest studies. However, progress has been slower for myeloid leukemia and certain subgroups like infant ALL, adolescent/young adult ALL, and relapsed ALL. Recent advances include recognition of molecularly defined subgroups, which has ushered in precision medicine approaches. We discuss the current understanding of the biology of the various childhood leukemias, recent advances in research, and future challenges in this field.

The expanding role of primary care in cancer control

The nature of cancer control is changing, with an increasing emphasis, fuelled by public and political demand, on prevention, early diagnosis, and patient experience during and after treatment. At the same time, primary care is increasingly promoted, by governments and health funders worldwide, as the preferred setting for most health care for reasons of increasing need, to stabilise health-care costs, and to accommodate patient preference for care close to home. It is timely, then, to consider how this expanding role for primary care can work for cancer control, which has long been dominated by highly technical interventions centred on treatment, and in which the contribution of primary care has been largely perceived as marginal. In this Commission, expert opinion from primary care and public health professionals with academic and clinical cancer expertise—from epidemiologists, psychologists, policy makers, and cancer specialists—has contributed to a detailed consideration of the evidence for cancer control provided in primary care and community care settings. Ranging from primary prevention to end-of-life care, the scope for new models of care is explored, and the actions needed to effect change are outlined. The strengths of primary care—its continuous, coordinated, and comprehensive care for individuals and families—are particularly evident in prevention and diagnosis, in shared follow-up and survivorship care, and in end-of-life care. A strong theme of integration of care runs throughout, and its elements (clinical, vertical, and functional) and the tools needed for integrated working are described in detail. All of this change, as it evolves, will need to be underpinned by new research and by continuing and shared multiprofessional development.

Ph-negative isolated myeloid sarcoma with NPM1 gene mutation in adolescent with Ph-positive chronic myeloid leukemia in remission after treatment with allogeneic bone marrow transplantation and imatinib mesylate

Few patients in remission of Ph-positive chronic myelogenous leukemia (CML) develop Ph-negative MDS/AML, usually with clonal cytogenetic abnormalities. Isolated Ph-negative myeloid sarcoma (MS) is presented here as a form of such disorder, different from Ph-positive MS establishing CML relapse in blastic phase. We describe 11-year-old male who developed Ph-negative isolated MS with NPM1 mutation, remaining in complete molecular remission of Ph-positive chronic myeloid leukemia treated with allo-HSCT in first chronic phase and with imatinib and donor lymphocyte infusion in molecular relapse. The possible mechanisms of the tumor formation are reviewed with stress on importance of comprehensive molecular/cytogenetic evaluations.

Isolated primary intracranial myeloid sarcoma with neuromeningeal infiltration: A case report

Myeloid sarcoma is a rare extramedullary malignant tumor, which is often accompanied by the development of systemic myeloid disease at various sites. The involvement of the central nervous system is uncommon and spinal cord compression is particularly rare. In November 2012, a 27-year-old male presented with a paroxysmal headache, accompanied by nausea and vomiting, which had persisted for one year, and eyesight deterioration that had been apparent for five months. Magnetic resonance imaging (MRI) indicated a space-occupying disorder, a craniotomy to resect the brain tumor was undertaken, the pathological diagnosis of which was myeloid sarcoma. Two months after receiving 40 Gy of radiotherapy, the patient experienced numbness of the right thigh. MRI of the lumbar spinal canal revealed a mass involved both inside and outside the lumbar spinal canal. Pathological examination of the mass following resection also indicated myeloid sarcoma. Immunohistochemical analysis was positive for the ETO fusion gene in the bone marrow. Following six cycles of chemotherapy treatment, the patient achieved complete remission. At present, the patient is stable and is attending follow-up examinations regularly.

A Case of Acute Myeloid Leukemia (FAB M2) with Inversion 16 Who Presented with Pelvic Myeloid Sarcoma

Acute leukemias are the most common childhood cancer in all age groups. Acute myeloid leukemias (AML) constitute about 15–20% of acute leukemias. Fatigability, pallor, fever, and bleeding are the most common presenting symptoms of AML. Hepatosplenomegaly and lymphadenopathy are commonly encountered during physical examination. In rare instances eruptions due to skin involvement and localized tumor masses (myeloid sarcoma) may be found. Myeloid sarcoma is especially seen in AML-M2 subtype. By cytogenetic analysis, in AML-M2 subtype t(8;21) is often seen and it is more probable to find inversion 16 in AML-M4Eos subtype. Herein, we present a 15-year-old girl whose initial symptom was abdominal pain for three days and her pathological sign was a large abdominal mass which was verified by imaging studies and diagnosed as myeloid sarcoma by biopsy. On bone marrow examination, she had diagnosis of AML-M2 and by cytogenetic analysis inversion 16 was positive. She was treated with AML-BFM 2004 protocol and she is being followed up in remission on her ninth month of the maintenance therapy.

Early therapy-related myeloid sarcoma and deletion of 9q22.32 to q31.1

Survival following childhood neuroblastoma is improving with low rates of secondary myeloid neoplasms. We describe a 13-month-old male with intermediate risk neuroblastoma who developed an isolated scalp therapy-related myeloid sarcoma (t-MS). Developmental delays and two distinct malignancies prompted constitutional evaluation. Chromosomal microarray identified a 7.3 Mb deletion of 9q22.32 to 9q31.1. He remains in remission 11 months following hematopoietic cell transplant. Unusual presentations of rare diseases necessitate a multidisciplinary approach and adaptation of standardized protocols to accommodate increased risks imposed by genetic variants.

Pulmonary presentation of relapsed acute myeloid leukemia

Extramedullary manifestations of acute myeloid leukemia (AML), often referred to as myeloid sarcoma (MS), occur relatively commonly in children with newly diagnosed or relapsed AML and have been associated with certain French-American-British morphologies and gene/chromosomal rearrangements. The most common locations of MS include the skin, orbit, skeleton, central nervous system, skin, and gut. Pulmonary MS is uncommon in adults and is extremely rare in children. We report the case of a 19-year-old man with French-American-British M5 AML, who before bone marrow transplant, presented with fever, hypotension, and respiratory symptoms that were ultimately attributed to pulmonary MS.

Delays in diagnosis of paediatric cancers: a systematic review and comparison with expert testimony in lawsuits

Delayed diagnosis of paediatric cancers is reported regularly and is a source of remorse for physicians and parents and a leading cause of malpractice claims. We did a systematic review of information about the distribution, determinants, and consequences of time to diagnosis of paediatric malignancies and compared these findings with those of court-appointed expert witnesses in malpractice claims in Canada and France. Time to diagnosis varied widely between tumour types in the 98 relevant studies (medians ranged from 2-260 weeks) without any significant decrease with time. Determinants of a long delay in diagnosis included older age, qualification of the first physician contacted, non-specific symptoms, histological type, and tumour localisation. Delayed diagnosis was associated with poor outcome for retinoblastoma and possibly for leukaemia, nephroblastoma, and rhabdomyosarcoma (data were insufficient for definitive conclusions). It was not associated with an adverse outcome for most CNS tumours, osteosarcoma or Ewing's sarcoma, and, paradoxically, was frequently associated with better outcomes than was short time to diagnosis in these cancers. A third of the court-appointed experts provided testimony concordant with the medical literature. The relations between delay in diagnosis and outcome are complex and probably depend more on tumour biology than on parental or medical factors.

Diagnosis and management of acute myeloid leukemia in children and adolescents: recommendations from an international expert panel

Despite major improvements in outcome over the past decades, acute myeloid leukemia (AML) remains a life-threatening malignancy in children, with current survival rates of ∼70%. State-of-the-art recommendations in adult AML have recently been published in this journal by Döhner et al. The primary goal of an international expert panel of the International BFM Study Group AML Committee was to set standards for the management, diagnosis, response assessment, and treatment in childhood AML. This paper aims to discuss differences between childhood and adult AML, and to highlight recommendations that are specific to children. The particular relevance of new diagnostic and prognostic molecular markers in pediatric AML is presented. The general management of pediatric AML, the management of specific pediatric AML cohorts (such as infants) or subtypes of the disease occurring in children (such as Down syndrome related AML), as well as new therapeutic approaches, and the role of supportive care are discussed.

Superior outcome of pediatric acute myeloid leukemia patients with orbital and CNS myeloid sarcoma: a report from the Children's Oncology Group

BACKGROUND

Extramedullary leukemia (EML) is common in pediatric acute myeloid leukemia (AML) and occurs as leukemia cells within the cerebrospinal fluid (CSF) or as a solid tumor (myeloid sarcoma-MS). The effect of MS on survival is unknown.

METHODS

Patients on CCG protocols 2861, 2891, 2941, and 2961 being treated for AML with intensive-timing chemotherapy were classified for the presence of EML (CSF leukemia, CNS-MS, orbital-MS, or non-CNS MS). CSF leukemia was classified as CNS3 (>5 WBC in the CSF with blasts) and non-CSF leukemia as CNS1/2 (<5 WBC in the CSF with or without blasts). Characteristics and outcomes of these patients were compared.

RESULTS

Of the 1,459 total patients, 1,206 (82%) had no EML, 154 (11%) had CSF leukemia, 19 (1%) had CNS-MS, 23 (2%) had orbital-MS, and 57 (4%) had non-CNS MS. The CR rate was significantly higher in patients with orbital-MS and CNS-MS than in those with non-MS and non-CNS MS (96% and 95% vs. 78% and 78%, P = 0.034). Patients with orbital-MS and CNS-MS had significantly higher overall survival than patients with non-CNS MS (92% and 73% vs. 38%, P < 0.001), CNS3 patients (92% and 73% vs. 51, P < 0.001), and CNS1/2 patients (92% and 73% vs. 50%, P < 0.001). Patients with orbital-MS had a significantly lower relapse rate.

CONCLUSION

Patients with MS involving orbital and CNS sites had a significantly better survival than patients with non-CNS MS, with CSF leukemia, or with no EML.

How I treat extramedullary acute myeloid leukemia

Extramedullary (EM) manifestations of acute leukemia include a wide variety of clinically significant phenomena that often pose therapeutic dilemmas. Myeloid sarcoma (MS) and leukemia cutis (LC) represent 2 well-known EM manifestations with a range of clinical presentations. MS (also known as granulocytic sarcoma or chloroma) is a rare EM tumor of immature myeloid cells. LC specifically refers to the infiltration of the epidermis, dermis, or subcutis by neoplastic leukocytes (leukemia cells), resulting in clinically identifiable cutaneous lesions. The molecular mechanisms underlying EM involvement are not well defined, but recent immunophenotyping, cytogenetic, and molecular analysis are beginning to provide some understanding. Certain cytogenetic abnormalities are associated with increased risk of EM involvement, potentially through altering tissue-homing pathways. The prognostic significance of EM involvement is not fully understood. Therefore, it has been difficult to define the optimal treatment of patients with MS or LC. The timing of EM development at presentation versus relapse, involvement of the marrow, and AML risk classification help to determine our approach to treatment of EM disease.

Pediatric head and neck extramedullary hematopoietic disease: case series and review of the literature

We review 3 pediatric cases of extramedullary hematopoietic disease occurring in the orbit, ethmoid sinuses, and parotid gland, and present a review of the literature. Each of the 3 patients was taken to the operating room, and the biopsy specimens obtained were successful in establishing the diagnosis in every case. Head and neck manifestations of extramedullary hematopoietic disease are rare, indeed. However, these cases demonstrate that it is important for otolaryngologists, pediatricians, primary-care physicians, radiologists, and pathologists to maintain a high index of suspicion for extramedullary presentations of hematopoietic disease in the head and neck. A coordinated multidisciplinary approach, including the appropriate surgical approach for biopsy, will facilitate determination of the diagnosis and treatment plan.

A simple case of a small elbow effusion

An 11-month-old child presented with what initially appeared to be 2 simple problems, a small elbow effusion followed 1 week later by croup. This case history is presented to remind emergency medicine physicians of the importance of index of suspicion and recognition of the difference between common events occurring in a normal host versus common events occurring in an abnormal host.

Acute myeloid leukemia in a young girl presenting with mediastinal granulocytic sarcoma invading pericardium and causing superior vena cava syndrome

A 1-year-4-month-old girl who presented with pericardial effusion and superior vena cava (SVC) syndrome caused by a mediastinal mass was later proved to be a case of acute myeloid leukemia (AML) with mixed-lineage leukemia-gene translocation. The unusual presentation and the giant blasts with basophilic vacuolated cytoplasm had led to initial misdiagnosis of mediastinal lymphoma. She developed progressive SVC syndrome, unresolved pericardial effusion, and extensive leukemia cutis after initial induction therapy. She died soon after second-course chemotherapy. To our knowledge, this is the first reported case of childhood acute myeloid leukemia presenting with mediastinal granulocytic sarcoma causing pericardium invasion and SVC syndrome.

Translocation (1;10)(p34;p15) in infant acute myeloid leukemia with extramedullary infiltration in multiple sites

Primary acute myeloid leukemia (AML) with extramedullary infiltration (EMI) in multiple sites is rare. Herein, we describe a case of infant AML with EMI in multiple sites. She had dyspnea and hypofibrinogenemia at diagnosis, and systemic computed tomography revealed EMI in the orbit, gingiva, bronchial pathway, and urinary tract. Bone marrow examination confirmed the diagnosis of AML with t(1;10)(p34;p15). No case of AML with t(1;10)(p34;p15) has been reported in the literature. At the present time, she remains free of disease 12 months after bone marrow transplantation (BMT) in the second complete remission.

Leukemia presenting as solid tumors: report of four pediatric cases and review of the literature

Leukemias are neoplasms that arise from the hematopoetic cells of bone marrow and usually spread first to peripheral blood. Involvement of extramedullary tissue during the course of a leukemia is common and usually does not represent a major diagnostic challenge when the history is available and specimen triage is optimal. In the context of a myeloid origin, extramedullary leukemias are referred to as granulocytic sarcomas, extramedullary myeloid tumors, extramedullary leukemias, or myeloid sarcomas. In the lymphoid category, leukemia involvement of tissue is conventionally distinguished from lymphoma by establishing the presence of 20% or more blasts in the bone marrow. A leukemia with an initial presentation outside the bone marrow mimicking a solid tumor is a rare but well-documented clinical encounter. Diagnostic difficulties may arise, especially when a specimen is not triaged properly due to the clinical presumption of a nonhematopoietic tumor. Systematic handling and proper triaging of biopsies are the keys to reducing diagnostic error and facilitating a timely diagnosis in this category. We report 4 case examples in the pediatric population, presenting in different anatomic sites. The value of fresh specimens and performing touch imprints is discussed and emphasized.

[Livid polycyclic plaques of the lower extremities]

In 10%-55% of patients, leukemia cutis (LC) manifest as a symptom of acute myelomonocytic leukemia and is associated with a poor overall prognosis. Disseminated bluish-violet or red-brownish papules and plaques, nodules and also hemorrhagic ulcers may dominate the initial clinical picture. Importantly, nonspecific infiltrates (leukemids) must be differentiated from specific infiltrates of malignant cells in patients presenting with dermatoses and concomitant underlying hematopoietic neoplasms. The role of the dermatologist is the rapid clinical and dermatohistopathological diagnosis in order to allow immediate, adequate treatment of the patient's underlying systemic disease.

Spontaneous resolution of a single lesion of myeloid leukemia cutis in an infant: case report and discussion

Though infantile leukemia has a historically poor prognosis, there may be a subset of patients with cutaneous disease whose disease will resolve without therapy. The authors report a case of infantile leukemia cutis who presented with a single subcutaneous chloroma that spontaneously resolved over the course of several weeks and who remains without evidence of disease nearly two years later. After reviewing the literature of congenital leukemia cutis, the authors conclude that withholding chemotherapy in infants with cutaneous myeloid leukemia in the absence of known negative prognostic factors (MLL or BCR-ABL translocations) or progressive disease is clinically indicated.

Presentation of acute promyelocytic leukemia as granulocytic sarcoma

Granulocytic sarcoma (GS) is a localized tumor composed of immature myeloid cells. This extramedullary tumor can present before, concurrent with or after the diagnosis of acute myeloid leukemia. GS is extremely uncommon in acute promyelocytic leukemia (APL). As a proportion of patients never develop systemic disease, correct and timely diagnosis may be rather difficult, but is a prerequisite for optimal outcome. GS should be considered in the differential diagnosis of children with unusual bone lesions. We describe a patient with GS who presented with symptoms mimicking osteomyelytis or rheumatoid disease.

Precursor B lymphoblastic leukemia 32 months after local therapy for a primary extramedullary myeloid cell tumor

A primary extramedullary myeloid cell tumor (pEMT) of an inguinal lymph node was completely excised without subsequent anti-tumor therapy in a 6-year-old child. Clinical observation and monitoring of blood and bone marrow (BM) did not reveal any pathologic results before 32 months, when a precursor B lymphoblastic leukemia was diagnosed. Identical T-cell receptor gamma rearrangement in nodal pEMT and in precursor B lymphoblastic leukemia in BM indicates a clonal relationship of these two tumors.

Myeloid sarcoma presenting with bilateral proptosis and kidney infiltration

The authors describe a male infant with a history of transient pancytopenia who developed progressive bilateral proptosis associated with diffuse infiltration of the kidney and normal bone marrow. The histopathological examination of the kidney revealed diffuse infiltration of cells of myeloid origin with monocytic differentiation. Although orbital involvement by myeloid sarcoma, with or without concurrent acute myeloid leukemia, is well known, there are distinctive features in this patient that are not reported in the literature, namely bilateral proptosis and simultaneous presence of bilateral kidney infiltration, which enabled diagnosis.

Testicular chloroma in a nonleukemic infant

Extramedullary myeloid cell tumors (EMCT) are localized collections of immature myeloid cells that occur outside of the bone marrow. Usually observed concurrently with bone marrow disease, EMCT also may occur in the absence of overt marrow leukemia. In this report, we describe an infant with a testicular mass that was identified as an EMCT after orchiectomy. Unlike the only previously reported case of infantile testicular chloroma, this patient did not exhibit bone marrow disease at diagnosis. Because systemic chemotherapy is considered to be superior to local control (surgery, radiation therapy), the patient was treated with intensively timed induction chemotherapy followed by 3 cycles of maintenance treatment (according to CCG protocol #2891) but no radiation therapy. The patient remains disease-free 18 months after diagnosis.

Granulocytic Sarcoma Presenting with Severe Adenopathy (Cervical Lymph Nodes, Tonsils, and Adenoids) in a Child with Juvenile Myelomonocytic Leukemia and Successful Treatment with Allogeneic Bone Marrow Transplantation

The occurrence of adenopathy in patients with myelodysplastic syndrome-associated extramedullary myeloid cell tumors has rarely been reported. We describe a 7-year-old girl with juvenile myelomonocytic leukemia who showed the novel chromosomal abnormality t(9;12)(p22;q24.1) and who developed severe adenopathy of the cervical lymph nodes, tonsils, and adenoids that was manifested as granulocytic sarcoma. Following chemotherapy, the patient underwent a conditioning regimen of busulfan, cyclophosphamide, and total body irradiation followed by successful allogeneic bone marrow transplantation from her single HLA locus-mismatched mother at 6 months after her diagnosis. The patient continues to be well and in remission 3 years after stem cell transplantation.