Myeloid sarcoma: more and less than a distinct entity.

Myeloid sarcoma (MS) is a distinct entity among myeloid neoplasms defined as a tumour mass of myeloid blasts occurring at an anatomical site other than the bone marrow, in most cases concomitant with acute myeloid leukaemia (AML), rarely without bone marrow involvement. MS may also represent the blast phase of chronic myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS). However, the clinical and molecular heterogeneity of AML, as highlighted by the 2022 World Health Organization (WHO) and International Consensus (ICC) classifications, indirectly define MS more as a set of heterogeneous and proteiform diseases, rather than a homogeneous single entity. Diagnosis is challenging and relies mainly on histopathology, immunohistochemistry, and imaging. Molecular and cytogenetic analysis of MS tissue, particularly in isolated cases, should be performed to refine the diagnosis, and thus assign prognosis guiding treatment decisions. If feasible, systemic therapies used in AML remission induction should be employed, even in isolated MS. Role and type of consolidation therapy are not univocally acknowledged, and systemic therapies, radiotherapy, or allogeneic hematopoietic stem cell transplantation (allo-HSCT) should be considered. In the present review, we discuss recent information on MS, focusing on diagnosis, molecular findings, and treatments also considering targetable mutations by recently approved AML drugs.

Isolated intracranial myeloid sarcoma: report of a case and review of the literature.

Myeloid sarcoma is a rare malignant tumor of primitive myeloid cell origin often associated with hematologic disorders. The central nervous system is rarely involved and differentiating between myeloid sarcoma and other tumors is not possible on imaging. Here we present the rare case of an isolated intracranial myeloid sarcoma, initially misdiagnosed radiologically as a meningioma, treated with surgical total resection and subsequent chemotherapy, with no signs of any hematological disorder at follow up. Differential diagnosis and management strategies, as well as follow-up implications are discussed along with literature review, which pointed out that only five cases with no further signs of hematological disorders at follow up have been described in the literature so far and this case has the longest follow up of them at 9 years.

Granulocytic Sarcoma Mimicking Cholesteatoma: Beware the Temporal Bone in Haematological Patients.

Granulocytic sarcoma is a myeloid neoplasm that can occur in isolation or in association with acute leukaemia. The temporal bone represents a sanctuary site for myeloid progenitors: granulocytic sarcoma may develop in this location before or concomitantly with the onset of acute leukaemia. This atypical presentation with clinical and radiological data that closely mimic those of cholesteatoma often delays an accurate diagnosis. We here describe the clinical case of a 28-year-old male with granulocytic sarcoma of the external auditory canal that preceded the relapse of promyelocytic leukaemia.

A clinical report of intracranial granulocytic sarcoma and a literature review.

BACKGROUND: Granulocytic sarcoma (GS), is also referred to as myeloid sarcoma. It is a solid mass formed by the primitive or immature myeloid cells extramedullary infiltration, which is commonly caused by acute myelogenous leukemia (AML) or chronic myelogenous leukemia (CML). It mainly involves bones, lymph nodes, skin and soft tissues of the head and neck. In general, the incidence is low and central nervous system (CNS) involvement is relatively rare. The clinical manifestations of the disease are varied and the treatment is intractable. CASE DESCRIPTION: A 53-year-old male with intracranial granulocytic sarcoma who suffered a pressing pain on the left cheek. The patient had a hypophasis with left corneal reflex diminished. He had bilateral anisocoria, lower jaw and tongue tilted to the left upon opening the mouth and the left pharyngeal reflex was declined. The whole blood routine was normal except for eosinophils, head magnetic resonance imaging plain scan revealed a space-occupying lesion. Postoperative pathology suggested GS. Unfortunately, the disease progressed quickly and the patient died. CONCLUSION: Isolated GS is often difficult to diagnose accurately. The patient's medical history should be carefully reviewed, all relevant tests should be performed, and various differential diagnoses should be familiarized with to improve the accuracy of diagnosis. And on this basis, to develop a personalized treatment plan for different patients.

Myeloid sarcoma of the heart: Extramedullary relapse of acute myeloblastic leukemia, presenting with complete heart block and atrial flutter after second allogeneic stem cell transplantation.

We report isolated extramedullary relapse in a 14-year-old boy, sequentially presenting with intestinal and cardiac myeloid sarcoma (MS). Acute myeloblastic leukemia M5 was diagnosed 41 months ago. On the 14th month of the second HSCT, he presented with ileus and underwent surgical treatment. After 2 weeks, arrhythmia, bradycardia, complete heart block, and atrial flutter developed and echocardiography revealed multiple cardiac masses. There was no bone marrow relapse but pathology of the intestinal biopsy showed leukemic infiltration. Patient was successfully treated with a permanent pacemaker and salvage chemotherapy. To the best of our knowledge, this is the first pediatric cardiac MS developed after HSCT.

[Acute promyelocytic leukemia recurrence diagnosed due to granulocytic sarcoma of the external auditory canal].

A 47-year-old man was diagnosed with acute promyelocytic leukemia (APL) accompanied by pancytopenia and left forearm swelling. Complete remission was achieved with remission induction therapy using all-trans retinoic acid (ATRA), and consolidation therapy was completed. Three months after the treatment, left ear closure was observed, and a mass lesion was found in the left external auditory canal. An initial tumor biopsy only revealed inflammatory cell infiltration. Moreover, the tumor's rebiopsy performed 3 months later revealed MPO-positive and CD68-positive granulocyte infiltration. Furthermore, the rebiopsy revealed 4.9×105 copies/µgRNA of PML/RARα, the patient was diagnosed with locally recurrent APL. A bone marrow examination 2 weeks later confirmed an increase in myeloblasts and promyelocytes for the first time since the confirmation of remission. Therefore, it was diagnosed as bone marrow recurrence. Reinduction therapy using ATRA and arsenic trioxide again led to complete remission, after which autologous peripheral blood stem cell transplantation was performed. Currently, complete remission is being maintained. In this case, the recurrence of the external auditory canal lesion preceded the bone marrow recurrence. Therefore, it is important to note the nonspecific leukemia recurrence patterns of the external auditory canal.

Clinical and imaging features of myeloid sarcoma: a German multicenter study.

BACKGROUND: Myeloid sarcoma (MS), also known as chloroma, is an extramedullary manifestation of malignant primitive myeloid cells. Previously, only small studies investigated clinical and imaging features of MS. The purpose of this study was to elucidate clinical and imaging features of MS based upon a multicenter patient sample. METHODS: Patient records of radiological databases of 4 German university hospitals were retrospectively screened for MS in the time period 01/2001 and 06/2019. Overall, 151 cases/76 females (50.3%) with a mean age of 55.5 ± 15.1 years and 183 histopathological confirmation or clinically suspicious lesions of MS were included into this study. The underlying hematological disease, localizations, and clinical symptoms as well as imaging features on CT and MRI were investigated. RESULTS: In 15 patients (9.9% of all 151 cases) the manifestation of MS preceded the systemic hematological disease. In 43 cases (28.4%), first presentation of MS occurred simultaneously with the initial diagnosis of leukemia, and 92 (60.9%) patients presented MS after the initial diagnosis. In 37 patients (24.5%), the diagnosis was made incidentally by imaging. Clinically, cutaneous lesions were detected in 35 of 151 cases (23.2%). Other leading symptoms were pain (n = 28/151, 18.5%), neurological deficit (n = 27/151, 17.9%), swelling (n = 14/151, 9.3%) and dysfunction of the affected organ (n = 10/151, 6.0%). Most commonly, skin was affected (n = 30/151, 16.6%), followed by bone (n = 29/151, 16.0%) and lymphatic tissue (n = 21/151, 11.4%). Other localizations were rare. On CT, most lesions were homogenous. On T2-weighted imaging, most of the lesions were hyperintense. On T1-weighted images, MS was hypointense in n = 22/54 (40.7%) and isointense in n = 30/54 (55.6%). A diffusion restriction was identified in most cases with a mean ADC value of 0.76 ± 0.19 × 10- 3 mm2/s. CONCLUSIONS: The present study shows clinical and imaging features of MS based upon a large patient sample in a multicenter design. MS occurs in most cases meta-chronous to the hematological disease and most commonly affects the cutis. One fourth of cases were identified incidentally on imaging, which needs awareness of the radiologists for possible diagnosis of MS.

Disseminated De Novo Myeloid Sarcoma in a 17-year-old Boy.

Myeloid sarcoma (MS) is a rare extramedullary tumor of malignant myeloid cells often associated with acute myeloid leukemia. We report a case of a 17-year-old boy presenting with diffuse red-brown skin nodules ultimately diagnosed with the scarcely described disseminated, de novo MS. It is important for dermatologists to keep MS on their differential when assessing patients with disseminated red-brown nodules.

Expression of programmed death ligand 1 is associated with poor prognosis in myeloid sarcoma patients.

Myeloid sarcoma (MS) is a rare condition and is an extramedullary tumour of immature myeloid cells. It is now known that the programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) pathway suppresses the host antitumor responses and that these products are expressed on both tumour cells and tumour-infiltrating cells in various malignancies. However, little is known about the significance of PD-1/PD-L1 expression on tumour cells and tumour microenvironmental cells in MS. To investigate the clinicopathological significance of PD-1/PD-L1 expression in MS, we analyzed 98 patients by immunohistochemistry. Of these, 10.2% of cases had neoplastic tumour cells positive for PD-L1 (nPD-L1+ ). However, the rate of nPD-L1+ was <5% (range: 0.27 to 2.97%). On the other hand, PD-L1 expression on 1 or more of stromal cells in the tumour microenvironment (miPD-L1+ ) was observed in 37.8% of cases. Because all nPD-L1+ cases expressed PD-1 on less than 5% of tumour cells, we compared the miPD-L1+ and miPD-L1- groups. There was a correlation between miPD-L1+ status and the number of PD-1-expressing tumour -infiltrating lymphocytes (PD-1+ TILs; P = .0229). miPD-L1+ was found to be associated with poorer overall survival and progression-free survival (P = .00392, P = .00261, respectively). Multivariate analysis also confirmed miPD-L1+ to be an independent poor prognostic factor. In conclusion, our study indicated that the immunotherapy blocking the PD-1/PD-L1 pathway may improve the clinical outcome of MS.

Clinicopathological characteristics of de novo and secondary myeloid sarcoma: A monocentric retrospective study.

OBJECTIVE: Diagnosing myeloid sarcoma remains challenging, and we aimed to provide clinicopathological features to facilitate diagnosis. METHOD: Clinicopathological data from 41 patients with de novo and 31 with secondary myeloid sarcoma were reviewed. RESULTS: Most de novo cases presented with isolated myeloid sarcoma (n = 19) or myeloid sarcoma with concurrent acute myeloid leukemia (n = 15). Most secondary cases presented after acute myeloid leukemia (n = 11), myeloproliferative neoplasm (n = 9), or myelodysplastic syndrome (n = 8). Most frequent localizations were skin and lymph nodes. Immunohistochemistry showed immature and/or aberrant antigenic expression in 29% of de novo and 39% of secondary cases. Most genetic abnormalities were RUNX1-RUNX1T1 (n = 4), CBFB-MYH11 (n = 2), KMT2A-MLLT3 (n = 2), and JAK2 V617F (n = 2) mutations in de novo myeloid sarcoma, and BCR-ABL1 (n = 5) and KMT2A rearrangements (n = 2) in secondary cases. A complex karyotype was seen in 17% of de novo and 39% of secondary cases. Most prevalent treatment was induction chemotherapy followed by consolidation chemotherapy (n = 10) or allogeneic stem cell transplantation (n = 9) for de novo and radiotherapy (n = 11) for secondary cases. CONCLUSION: De novo myeloid sarcoma mostly presented isolated. Lesions were often localized at skin and lymph nodes. Genetic aberrations frequently involved core-binding factor rearrangements in de novo cases and a complex karyotype in secondary cases.

[Clinical outcome of allogeneic hematopoietic stem cell transplantation in the treatment of 9 myeloid leukemia patients with granulocytic sarcoma].

To explore the efficacy and influencing factors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with myeloid leukemia and granulocytic sarcoma (GS). Clinical outcome including hematopoietic reconstitution, transplant-related complications, survival and relapse were collected and retrospectively analyzed in 9 patients with myeloid leukemia and GS after allo-HSCT. Hematopoiesis reconstitution was achieved in all the 9 recipients. Four cases developed acute graft-versus-host disease (GVHD), and 1 with chronic GVHD. The median follow-up time after transplantation was 10(4-81) months. Only 2 cases survived, the other 7 died of relapse. The median time of relapse after transplantation was 5(3-19) months. Allo-HSCT is relatively effective treatment for patients with myeloid leukemia and GS. Relapse after transplantation remains the major factor of mortality.

Hematolymphoid lesions of the breast.

Hematolymphoid malignancies of the breast are most commonly neoplasms of mature B-lymphocytes, and may arise as a primary disease or by secondary involvement of a systemic disease. Primary breast lymphomas (PBL) account for 0.04-0.5% of breast malignancies, less than 1% of all non-Hodgkin's lymphomas (NHL), and less than 5% of extranodal lymphomas (Lakhani et al., 2012; Swerdlow et al., 2008; Joks et al., 2011; Barista et al., 2000; Giardini et al., 1992; Brogi and Harris, 1999; Topalovski et al., 1999).1-7 Secondary breast lymphomas (SBL) are also rare, with an estimated annual incidence of 0.07% (Domchek et al., 2002; Talwalkar et al., 2008).8,9 Recognition of breast lesions as hematolymphoid is critical to distinguish them from other entities that can occur in the breast.

Chemotherapy Options for Poor Responders to Neoadjuvant Chemotherapy for Orbital Granulocytic Sarcoma.

OPINION STATEMENT: Granulocytic sarcoma (GS) is a rare manifestation of myeloid proliferation, characterized by formation of a mass comprised of immature cells of myeloid origin. Orbital granulocytic sarcoma is rarer still, with only a small fraction of GS patients having orbital involvement. Given the rarity of orbital GS, no unified therapy plan has been identified, as large prospective trials are not feasible, but it is widely accepted that patients with GS ought to be treated with systemic intensive chemotherapy consistent with standard of care regimens for acute myelogenous leukemia (AML) or chronic myelogenous leukemia (CML). Development of a treatment plan for GS in poor responders involves a systemic leukemia plan as novel therapeutics have not been investigated for treatment GS per se, but used more widely for AML. GS is most commonly associated with AML and thus will be addressed in that context in this review. Patients with GS associated with CML should receive CML-specific therapy. When conventional and traditional cytotoxic GS/AML chemotherapy regimens are insufficient, patients often require a combination of novel therapeutics, stem cell transplantation (SCT), and radiation. Much of the recent advancement in AML therapy, as well as in AML translational research, has been in targeting molecular facets of the disease and enabling more specificity with treatment. The aim of treating patients for whom conventional treatment was unsuccessful with personalized therapy has not yet been realized, but many of the novel therapeutics reviewed below have demonstrated promise and are cause for optimism. In our center, when a GS/AML patient is refractory to frontline therapy, we rely on novel chemotherapy therapeutic options as outlined below.

Myeloid sarcoma of the orbit without systemic recurrence of disease in an adult: A clinicopathological case report.

Myeloid sarcoma (MS), also known as granulocytic sarcoma (GS) or chloroma (named for the greenish hue attributed to the pigment of myeloperoxidase [MPO]), is a rare solid tumor with a predilection for the orbit. MS usually occurs in conjunction with acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), or myeloproliferative disorder (MPS) and may be the harbinger of disease. Therefore, prompt diagnosis is essential for patient survival. We present a rare case of a 61 year old with an isolated orbital MS without active leukemia.

[Primary granulocytic sarcoma of lacrimal gland]. / Pervichnaia mieloidnaia sarkoma sleznoi zhelezy.

The article presents clinical description and instrumental findings (ultrasound examination and multi-slice computed tomography of the orbits) of a rare lacrimal gland tumor, which precedes or concurs with acute myeloblastic leukemia. Due to the low incidence of myeloid (granulocytic) sarcoma, it is not possible to develop a proper algorithm for its diagnosis and treatment. Few descriptions that are available in the literature neither give an idea of the variety of manifestations and the order of organ involvement, nor allow any vital prognosis. Verification of the diagnosis can only be based on immunohistochemical findings of the primary tumor and bone marrow biopsy material. The authors emphasize the importance of combination treatment (radiation therapy of the orbits and chemotherapy) in the prevention of leukemia.

Eyelid myeloid sarcoma: ominous presentation of acute myelogenous leukemia.

A 19 year-old African American man presented to our clinic for a second opinion about a right upper eyelid mass which had been recalcitrant to treatment for nonspecific orbital inflammation by an outside facility. Examination for systemic causes of the patients eyelid lesion led to a diagnosis of acute myelogenous leukemia (AML) FAB subtype M1. A subsequent biopsy of the eyelid tumor confirmed the diagnosis of a myeloid sarcoma. The patient succumbed to complications from his leukemia within 13 months of presentation. This case report is the first, to our knowledge, of an eyelid myeloid sarcoma as the presenting sign of AML and demonstrates the poor prognosis of this lesion.

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.

A practical approach to diagnose soft tissue myeloid sarcoma preceding or coinciding with acute myeloid leukemia.

Myeloid sarcoma involving soft tissue is rare and may present a pathologic diagnostic challenge, particularly when it precedes or coincides with hematological malignancies. Furthermore, it may mimic non-Hodgkin lymphoma, poorly differentiated carcinoma, melanoma, or round blue cell tumors, which is a potential diagnostic pitfall. In addition to a retrospective review of myeloid sarcoma (MS) cases seen at our institution, we describe differential diagnoses, diagnostic pitfalls, and practical approaches to diagnosing soft tissue MS preceding or coinciding with acute myeloid leukemia. Our institutional retrospective review (1999-2011) of MSs identified 12 cases of MS in which there was no known blood or bone marrow involvement at diagnosis. A panel of immunohistochemical stains and/or flow cytometry was reviewed; marker selection was subject to the pathologist's discretion. These tumors were consistently positive for CD117 (9/9), CD43 (7/7), myeloperoxidase (8/10), CD68 (4/5), and CD34 (5/9) by flow cytometry and/or immunohistochemistry. We also described a referral case, which had classic MS morphology and a myelomonocytic immunophenotype including positivity for CD45, lysozyme, and CD117 with supporting molecular information. Based on our institution's experience and review of the literature, we recommend that when the index of suspicion for MS is high, an immunohistochemical stain and/or flow cytometry panel should include CD43, lysozyme, CD117, CD68, CD33, Human Leukocyte Antigen DR (HLA-DR), and myeloperoxidase, in addition to thorough review of the patient's history, cytogenetic studies, and proper discussion with the clinician.

Orbital mass secondary to acute lymphoblastic leukaemia in a child: a rare presentation.

We report the case of a 3-year-old child, who presented with lid swelling which progressed to proptosis of the left eye. He also had systemic symptoms of fatigue and weight loss. An examination revealed hepatosplenomegaly and lymph node enlargement. Investigations showed a peripheral smear with blast cells, which were also revealed through a bone marrow biopsy. A CT scan showed a mass lesion in the left orbit that had infiltrated into the surrounding tissues. He was diagnosed with acute lymphoblastic leukaemia (ALL) with left-sided orbital mass secondary to it. Haematogenous masses in the orbit are commonly due to granulocytic sarcomas, which are usually associated with acute myelogenous leukaemia (AML), not ALL, and are rare especially when they precede systemic disease.