Diagnostic Challenges of Aleukemic Myeloid Sarcoma.

Myeloid sarcoma (MS) represents a neoplastic proliferation characterized by immature myeloid precursor cells. Among its variants, aleukemic MS is an uncommon subtype, manifesting as skin involvement sparing the peripheral blood or bone marrow. The non-specific cutaneous presentation coupled with the lack of associated symptoms poses a diagnostic challenge for providers. In this report, we present a case of an 83-year-old woman who presented with violaceous nodules located in the center of her right shin. A biopsy of the lesion unveiled a diagnosis of MS, yet notably lacked peripheral blood involvement. Three months after the initial diagnosis, the MS was found in the common bile duct, still without bone marrow involvement. With a relatively poor prognosis, the rapid diagnosis and treatment of MS are crucial.

Aleukemic variant of T-cell large granular lymphocyte leukemia in patients with rheumatoid arthritis - diagnostically challenging subtype.

INTRODUCTION: The typical clinical manifestations of T-cell large granular lymphocyte (T-LGL) leukemia are an increase in the number of large granular lymphocytes (LGLs) in the blood > 2000 cells/µL, neutropenia, and splenomegaly. In rare cases of so-called 'aleukemic' T-LGL leukemia, the number of LGLs is <400-500 cells/µL. In patients with rheumatoid arthritis (RA), distinguishing T-LGL leukemia with low tumor burden in the blood and bone marrow from Felty syndrome (FS) poses diagnostic challenges. AREAS COVERED: This review aimed to describe the basic characteristics and variants of aleukemic T-LGL leukemia, with a special focus on aleukemic T-LGL leukemia with massive splenomegaly (splenic variant of T-LGL leukemia) and differential diagnosis of such cases with hepatosplenic T-cell lymphoma. The significance of mutations in the signal transducer and activator of transcription 3 (STAT3) gene for distinguishing aleukemic RA-associated T-LGL leukemia from FS is discussed, along with the evolution of the T-LGL leukemia diagnostic criteria. PubMed database was used to search for the most relevant literature. EXPERT OPINION: Evaluation of STAT3 mutations in the blood and bone marrow using next-generation sequencing, as well as a comprehensive spleen study, may be necessary to establish a diagnosis of aleukemic RA-associated T-LGL leukemia.

Characteristics and treatment of acute myeloid neoplasms with cutaneous involvement in infants up to 6 months of age: A retrospective study.

BACKGROUND: Myeloid neoplasms account for 50% of cases of pediatric leukemias in infants. Approximately 25%-50% of patients with newborn leukemia have cutaneous extramedullary disease (EMD). In less than 10% of patients, aleukemic leukemia cutis or isolated extramedullary disease with cutaneous involvement (cEMD) occurs when skin lesions appear prior to bone marrow involvement and systemic symptoms. Interestingly, in acute myeloid leukemia with cutaneous EMD (AML-cEMD) and cEMD, spontaneous remissions have been reported. METHOD: This is a multicentric retrospective cohort study aiming to describe characteristics, treatment, and outcome of infants with either cEMD or presence of cutaneous disease with involvement of the bone marrow (AML-cEMD). This study included patients born between 1990 and 2018 from Italy, the Netherlands, Switzerland, and the United States, diagnosed between 0 and 6 months of life with cEMD or AML-cEMD. Descriptive statistics, Fisher's exact test, Kaplan-Meier method, and log rank test were applied. RESULTS: The cohort consisted of n = 50 patients, including 42 AML-cEMD and eight cEMD patients. The most common genetic mutation found was a KMT2A rearrangement (n = 26, 52%). Overall 5-year event-free survival (EFS) and overall survival (OS) were 66% [confidence interval (CI): 51-78] and 75% [CI: 60-85], respectively. In two patients, complete spontaneous remission occurred without any therapy. Central nervous system (CNS) involvement was found in 25% of cEMD patients. No difference in outcomes was observed between the AML-cEMD and cEMD groups, but none of the latter patients included in the study died. KMT2A rearrangements were not associated with poorer prognosis. CONCLUSION: In the largest cohort to date, our study describes the characteristics of infants with cutaneous involvement of myeloid neoplasms including cytomolecular findings and survival rates. Further prospective biologic and clinical studies of these infants with myeloid neoplasms will be required to individualize therapy for this rare patient population.

Aleukemic Chronic Myeloid Leukemia Without Neutrophilia and Thrombocytosis: A Report From the BCR::ABL1 Pathology Group.

Chronic myeloid leukemia (CML) is characterized by leukocytosis with left-shifted neutrophilia, basophilia, eosinophilia, and variable thrombocytosis. However, extremely rare cases of patients with CML without significant leukocytosis and thrombocytosis (aleukemic phase [ALP] CML, or CML-ALP) have been reported. Due to its rarity and limited awareness, there remains a significant knowledge gap concerning the pathologic diagnosis, disease progression, and optimal patient management and outcomes. In this multi-institutional study, we investigated 31 patients with CML-ALP. Over half (54.8%) of patients had a history of or concurrent hematopoietic or nonhematopoietic malignancies. At time of diagnosis of CML-ALP, approximately 26.7% of patients exhibited neutrophilia, 56.7% had basophilia, and 13.3% showed eosinophilia. The median number of metaphases positive for t(9;22)(q34;q11.2) was 15, with a median of 38.5% of interphase nuclei positive for BCR::ABL1 by fluorescence in situ hybridization. The median BCR::ABL1 level was 26.14%. Remarkably, 14 (45.2%) patients were initially misdiagnosed or not diagnosed before karyotype or fluorescence in situ hybridization information for BCR::ABL1 became available. Twenty-five patients received tyrosine kinase inhibitors (TKIs). One patient developed blast crisis while on TKI treatment 8 months after initial diagnosis. With a median follow-up time of 46.1 months, 20 of 22 patients who received TKI therapy and had detailed follow-up information achieved complete cytogenetic remission or deeper, 15 achieved major molecular remission or deeper, and 10 achieved molecularly undetectable leukemia. In conclusion, given the frequent occurrence of prior or concurrent malignancies, aleukemic presentation, and low level of t(9;22)(q34;q11.2)/BCR::ABL1, misdiagnosis or delayed diagnosis is common among these patients. While these patients generally respond well to TKIs, rare patients may develop blastic transformation. It is therefore important for pathologists and hematologists to be aware of this highly unusual presentation of CML to ensure timely diagnosis and appropriate management.

Myeloid sarcoma of the breast in an aleukemic patient:a rare entity in an uncommon location

Myeloid sarcoma (MS) is an extramedullary solid neoplasm of immature myeloid cells. These tumours usually develop in concurrence with or following acute leukemia. The breast is an uncommon site for presentation of this tumour, where it is often misdiagnosed as lymphoma or carcinoma.A 33- year-old female presented with a right breast lump in a private hospital, which was diagnosed as ductal carcinoma on lumpectomy. Subsequently she developed a lump in the left breast and a similar diagnosis of carcinoma was made on biopsy. A left mastectomy was performed. Histopathological examination revealed a tumour composed of mononuclear cells arranged in sheets and cords with round to oval vesicular nuclei and occasional prominent nucleoli. IHC for CK was very weak and focal. The tumour cells were immunonegative for ER, PR, Her2neu,epithelial membrane antigen, e-cadherin, CD3 and CD20. Diffuse immunopositivity for myeloperoxidase, CD34 and CD117 established a diagnosis of myeloid sarcoma. A histopathological review of the right breast lesion, with immunohistochemistry, also confirmed the diagnosis of myeloid sarcoma. Investigatory workup for acute myeloid leukemia, including bone marrow aspirate and biopsy and karyotypic studies, proved negative. The patient was treated with high dose cytarabine (HDAC) regimen and was disease free during the 12-month follow-up.Although extremely rare, awareness of such a presentation is crucial. This case also illustrates that careful histopathological review along with an expanded panel of immunohistochemistry is extremely important for recognizing such cases as a misdiagnosis can lead to unnecessary surgery and inappropriate therapy.

A Case of Systemic Mastocytosis Associated with Acute Myeloid Leukemia Terminating as Aleukemic Mast Cell Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation

In up to 40% of systemic mastocytosis (SM) cases, an associated clonal hematological non-mast cell lineage disease such as AML is diagnosed before, simultaneously with, or after the diagnosis of SM. A 40-yr-old man was diagnosed with AML with t(8;21)(q22;q22). Mast cells were not noted at diagnosis, but appeared as immature forms at relapse. After allogeneic hematopoietic stem cell transplantation (HSCT), leukemic myeloblasts were not observed; however, neoplastic metachromatic blasts strikingly proliferated during the state of bone marrow aplasia, and finally, aleukemic mast cell leukemia developed. As the disease progressed, we observed serial morphologic changes from immature mast cells with myeloblasts to only metachromatic blasts and atypical mast cells as mast cell leukemia; FISH analysis showed that the neoplastic mast cells originated from the same clone as the leukemic myeloblasts of AML.

Multiple Granulocytic Sarcomas in a Patient with Longstanding Complete Remission of Acute Myelogenous Leukemia

Granulocytic sarcoma is an extramedullary tumor composed of granulocytic precursor cells. It usually presents as a nodular mass in the course of acute myelogenous leukemia. Rarely, the tumor develops in non-hematological conditions or in a patient with complete remission from the acute myelogenous leukemia. In such cases, aleukemic granulocytic sarcoma can be a preceding sign of systemic leukemia or a first sign of hematologic relapse of leukemia. We present an unusual case of multiple granulocytic sarcomas developed in a patient with longstanding complete remission of acute myelogenous leukemia, who has not had bone marrow and peripheral blood involvement for a long time.

Ultrasound and MR Findings of Aleukemic Leukemia Cutis in a Patient with Complete Remission of Acute Lymphoblastic Leukemia: A Case Report

Aleukemic leukemia cutis is an extremely rare condition characterized by the infiltration of leukemic cells in skin without blasts in the peripheral blood. Leukemia cutis is considered a grave prognostic sign, thus early diagnosis is important. Leukemia cutis usually occurs in patients with myeloid leukemia. To the best of our knowledge, there has been no report regarding the radiological findings of aleukemic leukemia cutis, which is probably due to the presence of the skin changes in most patients. We report the ultrasound and MR findings of aleukemic leukemia cutis, even without the skin manifestation in patients with a history of complete remission of the acute lymphoblastic leukemia following an allogeneic peripheral blood stem cell transplantation.

A Case of Aleukemic Leukemia Cutis

Aleukemic leukemia cutis is a rare condition characterized by invasion of leukemic cells in the skin before their appearance in the peripheral blood or bone marrow. We report a case of a 24-year-old man who presented with a 2-month history of nodules on his chin and left thigh. His medical history included acute myelocytic leukemia which had been in complete remission for 13 years and seminoma of the right testis which had been treated with orchiectomy 1 year before. Biopsy of the cutaneous lesions revealed infiltrating cells characterized by irregular shaped or kidney bean-shaped nuclei with abundant pale, slightly eosinophilic cytoplasm. These atypical cells stained positive for leukocyte common antigen, lysozyme and myeloperoxidase. His peripheral blood examination and bone marrow biopsy failed to demonstrate leukemic changes. With these results, a diagnosis of aleukemic leukemia cutis was made. We then performed another immunohistochemical stain for lysozyme and myeloperoxidase on the testicular specimen which had been diagnosed as seminoma 1 year previously. The tumor cells of seminoma were lysozyme- and myeloperoxidase-positive. We were also able to diagnose seminoma as isolated granulocytic sarcoma. A complete remission of the cutaneous lesion was achieved with chemotherapy, but recurrent leukemia cutis reappeared six months later. He underwent a bone marrow transplant but died 3 months later.

A Case of Aleukemic Leukemia Cutis Occurring During Spontaneous Remission of Acute Myelomonocytic Leukemia / 대한피부과학회지

Aleukemic leukemia cutis is a rare condition characterized by the invasion of the skin by leukemic cells before their appearance in the peripheral blood. We report here a case, who had presented spontaneous remission of acute leukemia and 3 weeks later, have been relapsed in only the skin lesion without hematologic abnormalities. Through histopathological studies of skin lesion, the diagnosis of aleukemic leukemia cutis was made.

A Case of Acute Lymphoblastic Leukemia Preceded by Aleukemic Prodrome / 대한소아혈액종양학회지

Acute lymphoblastic leukemia (ALL), in general, can be diagnosed by detecting blasts in peripheral blood or bone marrow. Some of the cases of ALL do not show typical leukemic features, and only manifest as refractory anemia, thrombocytopenia, myelofibrosis and lymphocytic infiltration into bone marrow. Several months after presentation, they may reveal typical leukemic features and are diagnosed as ALL. This kind of leukemia is called ALL with aleukemic prodrome. Although the incidence of ALL with aleukemic prodrome is 1.5~2.2% of childhood ALL cases, it is rarely reported in Korea. We experienced a 6 month-old female infant who presented with refactory anemia and thrombocytopenia, and two serial of bone marrow examination revealed only myelofibrosis. She subsequently developed ALL 3 months later. We report this case with a brief review of related literatures.

Spinal epidural granulocytic sarcoma preceding acute myelogenous leukemia

A rare case of spinal epidural granulocytic sarcoma (GS) preceding acute myelogenous leukemia is described. A 10-year-old boy presented with lower leg weakness. The initial diagnosis was a histiocytic lymphoma, and he was treated accordingly. No evidence of bone marrow involvement was found at that time. The correct diagnosis of epidural GS was made possible in retrospect by using immunoperoxidase staining for lysozyme fourteen months later when the patient showed the full-blown features of leukemia. This rare tumor should be considered in the differential diagnosis of an epidural mass with cord compression in patients with or even without acute leukemia, because early diagnosis followed by appropriate combined chemotherapy and radiation may obviate surgical intervention and eventually prevent leukemic transformation.