Myeloproliferative Research Articles

Hemato-oncology services and COVID-19 Pandemic: The experience of Kazakhstan

Abstract Objectives The COVID-19 pandemic in Kazakhstan disrupted numerous healthcare services, including those critical for hemato-oncology patients, due to the strained healthcare system. This study examines how the COVID-19 pandemic has affected access to hemato-oncology healthcare services in Almaty, Kazakhstan. Methods We retrospectively analyzed patient data from two tertiary centers, City Clinical Hospital 7 (H7) and Kazakh Institute of Oncology and Radiology (KazIOR), from March 1, 2019, to February 28, 2022. Variables included age, gender, residence, hospitalization rate, treatment outcomes (discharged/deceased/transferred), diagnoses (acute leukemia, lymphoproliferative diseases, myeloproliferative diseases), and referral sources. The Statistical Yearbook of Kazakhstan provided comparative data. Results From 2019-2022, 6,763 hemato-oncology hospitalizations were registered: 3,583 in H7 and 3,180 in KazIOR. The mean age was 55.04 (SD = 16.07) for females and 51.2 (SD = 16.7) for males. Urban and rural patient proportions were 6,191 (92%) and 571 (8.4%), respectively (Chi-square 13.8, P = 0.001). Fewer patients were discharged in 2020-2021 (n = 2,047) compared to 2019-2020 (n = 2,387) and 2021-2022 (n = 2,081) (Chi-square 20.09, P = 0.003). The death rate was higher in 2020-2021 (3.5%) than in 2019-2020 (3.2%) and 2021-2022 (2.6%) (Chi-square 20.09, P = 0.003). Emergency admissions were 403 (19%) in 2020-2021, 368 (14.8%) in 2019-2020, and 394 (18.3%) in 2021-2022 (Chi-square 2,231, P < 0.001). Transfers from other hospitals increased by 12.4% in 2020-2021. Conclusions The COVID-19 pandemic negatively impacted access to hemato-oncology services, increasing mortality. Further studies are needed to understand the factors affecting hospitalization and mortality trends during healthcare crises. Funding: Grant No. AP09260497. Key messages • Access to healthcare services during COVID-19 pandemic for hemato-oncology patients. • Impact of the pandemic on access to healthcare.

Treatment of concomitant persistent chylothorax and superior vena cava syndrome through innominate vein-right atrial bypass.

Persistent chylothorax is a major challenge in paediatric patients. We present a case of a 6.5-kg, one-year-old boy with SVCS and persistent chylothorax, who underwent successful surgery without cardiopulmonary bypass. His medical history included multiple co-morbidities such as myeloproliferative disease, short bowel syndrome, and central vein catheterizations. The patient also had IV thrombosis, progressing to SVC, and was on anticoagulants. Despite dietary changes and somatostatin, his high-output chylous pleural effusion persisted. He was treated with innominate vein-to-right atrial bypass using a 6 mm Dacron graft. Postoperatively, there was a significant reduction in effusion and accelerated recovery. Somatostatin failure was likely due to mechanical obstruction of the thoracic duct.

The role of apheresis in the management of Philadelphia-negative chronic myeloproliferative syndromes following drug shortages

The role of apheresis in the management of Philadelphia-negative chronic myeloproliferative syndromes following drug shortages

Pyoderma Gangrenosum Associated With Iatrogenic Interleukin 17A Blockade: A Report of Two Cases andaReview of the Literature.

Pyoderma gangrenosum (PG) is a rare necrotizing neutrophilic dermatosis driven by monokines and cytokines elaborated by monocytes and autoreactive T cells, respectively. Th1-mediated autoimmune disorders and myeloproliferative disease are among the potential disease associations. More recently, certain medications were implicated, including TNF-alpha inhibitors, rituximab, and IL-17A inhibitors, such as secukinumab, where the development of PG is held to represent a cutaneous immune adverse effect. We present two patients who developed an autoinflammatory syndrome resembling PG in the setting of drug therapy with agents exhibiting an IL-17A inhibitory effect. The drugs were erunumab in one and secukinumab in the other. One patient received the anti-calcitonin gene-related peptide targeted therapy, erenumab, for migraine prophylaxis. While this drug has not been previously implicated in the development of PG, it can cause IL-17A blockade. The other patient was on secukinumab, a monoclonal antibody that selectively targets IL-17A. We documented a microenvironment enriched in IL-17A, emphasizing that the blockade impacts the functionality of the receptor as opposed to a quantitative reduction in IL-17A production by T cells. Qualitative functional IL-17A blockade could result in a paradoxical increase in IL-23, a pro-inflammatory cytokine that may contribute to the influx of neutrophils pathogenetically implicated in PG.

Dental implantation in patients with comorbid diseases: yes or no?

Patients with multiple pathologies are a high-risk group, which requires a personalized approach to surgical rehabilitation in dentistry. Inadequate diagnosis of clinical manifestations when a patient is in remission often leads to severe surgical complications. However, modern methods of dental implantation and rehabilitation are possible even in patients with oncology, those who underwent surgical therapy, chemo- or radiotherapy. Gilbert syndrome, one of the risk factors for post-surgery inflammatory complications, is associated with defects in bilirubin metabolism. It inhibits platelet activity. It is a genetic disease leading to a loss of liver enzyme activity and the accumulation of indirect bilirubin that can aggravate the course of other diseases in patients. In acute stages, it is characterized by jaundice of the skin, eyes, and mucosa and is followed by immunosuppression and the post-surgical complications associated with it. A patient with Gilbert syndrome was administered for surgical treatment of a chronic infection and follow-up rehabilitation via dental implantation and reconstruction of the bone. In this case, we faced Gilbert syndrome in association with polycythemia (a myeloproliferative disease in the compensation stage). In such cases, dental implantation cannot be achieved in the complex dental rehabilitation process. Such diseases require special attention from dental surgeons due to possible complications (bleeding, thrombosis, or disseminated intravascular coagulation). In this specific case, the patient belongs to the risk group, and its history, although in remission, is still a contraindication for dental surgery and dental implantation.

New approaches to standard of care in early-phase myeloproliferative neoplasms: can interferon-α alter the natural history of the disease?

The classical BCR::ABL-negative myeloproliferative neoplasms (MPN) include Polycythemia Vera (PV), Essential Thrombocytemia (ET), and Primary Myelofibrosis (PMF). They are acquired clonal disorders of the hematopoietic stem cells (HSC) leading to hyperplasia of one or several myeloid lineages. MPN are caused by three main recurrent mutations, JAK2V617F and mutations in the calreticulin (CALR) and the thrombopoietin receptor (MPL) genes. Here, we review the general diagnosis, the complications, and the management of MPN. Second, we explain the physiopathology of the natural disease development and its regulation, which contributes to MPN heterogeneity. Thirdly, we describe the new paradigm of the MPN development highlighting the early origin of driver mutations decades before the onset of symptoms and the consequence on early detection of MPN cases in the general population for early diagnosis and better medical management. Finally, we present the interferon alpha (IFNα) therapy as a potential early disease-modifying drug after reporting its good hematological and molecular efficacies in ET, PV and early MF in clinical trials as well as its mechanism of action in pre-clinical studies. As a result, we may expect that, in the future, MPN patients will be diagnosed very early during the course of disease and that new selective therapies under development, such as IFNα, JAK2V617F inhibitors and CALRmut monoclonal antibodies, would be able to intercept the mutated clones.

Prevention and treatment of transformation of myeloproliferative neoplasms to acute myeloid leukemia.

Philadelphia-chromosome negative (Ph-neg) myeloproliferative neoplasms (MPNs) are hematopoietic stem disorders with a risk of progression to the accelerated-phase (AP) or blastphase (BP) that is influenced by clinical, pathologic, cytogenetic, and molecular variables. Overall survival is limited in MPN-AP/BP with current treatment approaches, particularly in those patients that cannot receive an allogeneic hematopoietic stem cell transplant (allo-HCT). In addition, long-term survival with allo-HCT is predominantly seen in chronic-phase MPNs which suggests that the ideal time for intervention may be before MPNs evolve to AP/BP. Over the course of this review we will focus on the risk factors for progression to MPN-AP/BP, identification of high-risk chronic-phase MPNs, potential early-intervention strategies, and considerations around the timing of allo-HCT. We will also summarize current survival outcomes in MPN-AP/BP, discuss the uncertainty around how to best gauge response to therapy, and outline clinical trial considerations for this patient population. Lastly, we will highlight future directions in the management of high-risk MPNs.

Study on Heparin-Induced Thrombocytopenia and Blood Group among Individuals Suffering from Acute Coronary Syndrome

Background: Clinicians confront heparin-induced thrombocytopenia (HIT) as the most pertinent pathological relationship. Antibodies directed against complexes of heparin molecules and platelet factor 4 (PF4) are the cause of this immune-mediated phenomena. HIT is a significant adverse event that affects individuals with acute coronary syndromes (ACS). Objective: To assess the frequency of HIT in patients presenting with ACS. Materials and Methods: This study was carried out the Northeast Medical College's Department of Cardiology in Sylhet from June 2021 to December 2022. A total of 234 individuals aged 40 to 70 years old presented with ACS within 24 hours of symptom onset. This study excluded patients with idiopathic thrombocytopenic purpura (ITP), aplastic anemia, myeloproliferative diseases, or pre-existing thrombocytopenia. Thrombocytopenia was evaluated using medical records and a full blood count (CBC), with isolated thrombocytopenia (platelets <150 x109/L) prior to heparin administration. Results: Diabetes mellitus, hypertension, a history of ACS, and obesity were the most frequent comorbidities, accounting for 41.03%, 33.76%, 43.16%, and 14.96%, respectively. The incidence of HIT in NSTEMI and STEMI was higher than in unstable angina, although still comparable. The delayed presentation of ACS > 12 hours was also strongly correlated with the occurrence of HIT (p<0.05). Unstable angina and middle age (50–60 years) were found to have a significant relationship with HIT (p<0.05). Conclusion: HIT is more common in patients who have had a myocardial infarction or who have had symptoms for more than 12 hours at the time of hospitalization. Cardiologists and internal medicine experts must take extra precautions when administering heparin to high-risk patients to prevent problems.

Clinical characteristics associated with hospital-onset bacteremia and fungemia among cancer and transplant patients.

This study quantified the burden of hospital-onset bacteremia and fungemia (HOB) among cancer and transplant patients compared to other patients. A retrospective cross-sectional study used data from 41 hospitals between October 2015 and June 2019. Hospitalizations were segmented into categories using diagnosis-related groups (DRG): myeloproliferative (MP) cancer, solid tumor cancer, transplant, and non-cancer/non-transplant ("reference group"). To quantify the association between DRG and HOB, multivariable adjusted Poisson regression models were fit. Analyses were stratified by length of stay (LOS). Of 645,315 patients, 59% were female and the majority 41 years of age or older (76%). Hospitalizations with MP cancer and transplant demonstrated higher HOB burden compared to the reference group, regardless of LOS category. For all hospitalizations, the >30 days LOS category had a higher burden of HOB. The median time to reportable HOB was within 30 days regardless of duration of hospitalization (reference, 8 days; solid tumor cancer, 8 days; transplant, 12 days; MP cancer, 13 days). MP cancer and transplant patients had a higher burden of HOB compared to other hospitalized patients regardless of LOS. Whether these infections are preventable should be further evaluated to inform quality metrics involving reportable bacteremia and fungemia.

Reply to "Predictors of clinical outcome in myeloproliferative neoplasm, unclassifiable: a Bone Marrow Pathology Group study".

Reply to "Predictors of clinical outcome in myeloproliferative neoplasm, unclassifiable: a Bone Marrow Pathology Group study".

Regarding the predictors of clinical outcome in myeloproliferative neoplasm, unclassifiable

Regarding the predictors of clinical outcome in myeloproliferative neoplasm, unclassifiable

Can molecular patterns help to classify overlapping entities in myeloid neoplasms?

Myeloid neoplasms include myeloproliferative and myelodysplastic neoplasms and acute myeloid leukaemia. Historically, these diseases have been diagnosed based on clinicopathological features with sometimes arbitrary thresholds that have persisted even as molecular features were gradually incorporated into their classification. As such, although current diagnostic approaches can classify the majority of myeloid neoplasms accurately using a combination of molecular and clinicopathological features, some areas of overlap persist and occasionally pose diagnostic challenges. These include overlap across BCR::ABL1-negative myeloproliferative neoplasms; between clonal cytopenia of undetermined significance and myelodysplastic neoplasms; myelodysplastic/myeloproliferative neoplasms; and, detection of KIT mutations in myeloid neoplasms other than mastocytosis, raising the prospect of systemic mastocytosis. Molecular testing has become state of the art in the diagnostic work-up of myeloid neoplasms, and molecular patterns can inherently help to classify overlapping entities if considered within a framework of haematological presentations. For future development, molecular testing will likely include whole genome and transcriptome sequencing, and primarily molecular classifications of myeloid neoplasms have already been suggested. As such, genetically defined groups should still constitute the basis for our understanding of disease development from early onset to progression, while clinicopathological features could then be used to describe the stage of the disease rather than the specific type of myeloid neoplasm.

Newly diagnosed essential thrombocythemia leading to cardiogenic shock: a case report

BackgroundEssential thrombocythemia (ET) is a myeloproliferative neoplasm characterized by uninhibited platelet production. It can present with vasomotor symptoms, and less commonly, severe thrombotic events such as myocardial infarction. ST-segment elevation myocardial infarction (STEMI) secondary to the hypercoagulable state in ET is a diagnostic challenge as the complication is rare, especially outside the typical demographics affected by ET such as the female and elderly populations.Case presentationHere we report a case of a 32-year-old male found to have STEMI and a markedly elevated platelet count. Angiography revealed occlusion of the left anterior descending and left circumflex arteries, requiring percutaneous intervention and Impella support. The patient was later diagnosed with essential thrombocythemia, treated with hydroxyurea and antiplatelet therapy, and discharged with a wearable cardioverter defibrillator.ConclusionsThis case illustrates the potential for severe thrombotic complications such as STEMI due to ET. Severe thrombotic complications are less common manifestations of ET in general, particularly in young males. Recognition and diagnosis of ET are critical for the institution of appropriate therapy and prevention of STEMI and cardiogenic shock among other complications.

The CHIP-clinic as the catalyst of preventive medicine

Clonal Hematopoiesis of Indeterminate Potential (CHIP) is associated with an increased risk of cardiovascular diseases (CVD) and is a precursor stage to the BCR-ABL negative chronic myeloproliferative neoplasms (MPNs). These diseases are acquired stem cell neoplasms, arising due to mutations in the hematopoietic stem cell. The most prevalent is the JAK2V617F (JAK2) mutation, which potently generates reactive oxygen species (ROS), and accordingly contributes greatly to the chronic inflammatory state and the increased risk of thrombosis in MPNs. The MPNs are largely underdiagnosed blood cancers with a long pre-diagnostic phase of several years, when the elevated blood cell counts are considered reactive to smoking, blood clots, infections or chronic inflammatory diseases. Since the JAK2 mutation as CHIP-JAK2 associates with an increased risk of CVD and an increased risk of hematological and non-hematological cancers there is an urgent need to explore and validate the JAK2 mutation as a novel risk factor for CVD and to establish CHIP-clinics, which in an interdisciplinary collaboration between experts from several disciplines, and ensure timely diagnosis of the undiagnosed MPN patient and associated comorbidities. We envisage studies of the JAK2 mutation in large CVD cohorts to deliver the “Proof of Concept” for the JAK2 mutation to be implemented as a novel, highly important risk factor for CVD. These novel preventive strategies are considered to have the potential of reducing morbidity and mortality in a large population of citizens and patients, carrying the thrombosis- and CVD-promoting JAK2 mutation.

Ischemic stroke as a presenting feature of promyelocytic blast phase in chronic myeloid leukemia - an uncommon presentation: a case report and literature review in the post imatinib era.

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm (MPN characterized by reciprocal translocation in the ABL1 and BCR region of chromosomes 9 and 22 respectively. Progression to the blast phase in chronic myeloid leukemia results in a poorer prognosis. It can be of either myeloid, lymphoid or a mixed lineage. Progression to the promyelocytic blast phase is very rare, and there are no evidence-based guidelines for its management. Thrombosis in CML is not well defined. Thrombosis can be seen in patients with acute promyelocytic leukemia (APL) with venous thrombosis (VTE) being more common than arterial thrombosis. Ischemic stroke as the presenting feature of blast phase progression in CML is extremely rare. We report a case of CML who presented to us with acute ischemic stroke and subsequently was diagnosed as CML transformed to the promyelocytic blast phase. She was successfully treated with dasatinib along with all-trans retinoic acid (ATRA) and arsenic trioxide (ATO).

Pathomorphological diagnosis of Ph-negative chronic myeloproliferative neoplasms in children

Pathomorphological diagnosis of Ph-negative chronic myeloproliferative neoplasms in children

Myeloid Sarcoma of Conjunctiva in a patient with JAK2-positive myeloid neoplasm: two distinct myeloid neoplasms sequentially arising from a common precursor

Abstract Introduction/Objective Myeloid sarcoma (aka granulocytic sarcoma or chloroma), a rare type of myeloid neoplasm is characterized by the presence of myelogenous blastic cells outside of the bone marrow either before, during or after the development of leukemia. Presentation in the orbit is extremely rare, unlike other body parts. We report a case of myeloid sarcoma of conjunctiva in a patient with JAK2-positive myeloid neoplasm. Methods/Case Report An 84-year-old man presented with bilateral conjunctival masses which on biopsy showed diffuse involvement by blasts, immunohistochemically expressing positivity for myeloperoxidase, CD33, CD68, CD34 (partial), CD117 (partial) but were non-reactive to CD15, CD3 and PAX5. Next generation sequencing (NGS) revealed mutations in NRAS, ASXl1 and TET2 genes, consistent with the diagnosis of myeloid sarcoma (MS) of the conjunctiva. While patient’s past medical history included status post radiation and chemotherapy for prostate cancer and colonic adenocarcinoma respectively. it was also significant for a JAK 2 positive myeloproliferative neoplasm (MPN), six-years prior to current presentation. At the time he was treated with hydroxyurea for 5 years but developed neutrophilic leukocytosis and transfusion-dependent anemia. Subsequently a treatment regimen including ruxolitinib and pacritinib was initiated but without clinical and hematological improvements. NGS of the initial JAK2-positive MPN revealed ASXL1, JAK2 and TET2 mutations. Of note are the similarities and variations in the molecular signatures of patient’s initial MPN and current conjunctival MS. While the two neoplasms carried an identical TET2 mutation with highest variant allelic frequency, they are different in other mutations. Results (if a Case Study enter NA) NA Conclusion Our case illustrates an unusual manifestation of myeloid sarcoma localized to the conjunctiva. The identification of clonal relatedness on NGS with distinct mutations, adds complexity to our understanding of tumor origin. It highlights a series of events which may have contributed to this phenomenon, including consequence of therapy, clonal evolution with molecular discordance or origin as a totally independent entity. This report underscores the importance of genetic profiling in guiding prognosis and treatment strategies in such settings.

Myeloid neoplasm with concurrent BCR::ABL1 translocation, and JAK2 and SF3B1 co-mutations with severe fibrosis: a case report

Abstract Introduction/Objective Myeloproliferative neoplasms (MPNs) arise from hematopoietic stem cells with somatically altered tyrosine kinase signaling. Classification of MPNs is based on hematologic, histopathologic and molecular characteristics including the presence of BCR::ABL1 and JAK2 V617F. Methods/Case Report We present a 72-year-old male with a myeloid neoplasm and severe fibrosis, with concurrent BCR::ABL1 translocation, and co-mutations in JAK2 and SF3B1. Initially, the patient was diagnosed with anemia, thrombocytosis and folic acid deficiency and was prescribed supplemental folic acid. At follow up, normocytic anemia and thrombocytosis were seen. Bone marrow biopsy showed overtly fibrotic marrow with maturing trilineage hematopoiesis, markedly increased megakaryopoiesis and ring sideroblasts. Chromosome analysis and sequential GTG-fluorescence in situ hybridization (FISH) of metaphases using the dual-fusion three color probe BCR/ABL1- ASS1 revealed abnormal results. A t(9;22)(q34;q11.2) was detected along with an atypical FISH signal pattern with a single BCR::ABL1 fusion on the derivative chromosome 22 instead of the typical two fusions, resulting in loss of one BCR::ABL1 fusion signal including loss of the ASS1 on the derivative chromosome 9. Next-generation sequencing (NGS) analysis detected double driver mutations, JAK2 p. Val617Phe and SF3B1 p. Lys700Glu in the patient. JAK2 V617F mutation was further confirmed by real-time quantitative PCR (qPCR) with variant allele frequencies of 39.7%. Additionally, the patient was positive for BCR::ABL1 p190 fusion transcript (10%). The presence of JAK2 and SF3B1 co-mutations along with ring sideroblasts and the patient’s clinical presentation suggests the diagnosis of myelodysplastic/myeloproliferative neoplasm with thrombocytosis and SF3B1 mutation. Results (if a Case Study enter NA) NA Conclusion Although, the detection of t(9;22) by chromosome analysis is a diagnostic feature of chronic myeloid leukemia (CML), our case adds to the limited information on co-existence of BCR::ABL1 and JAK2 V617F with SF3B1 mutations in severe fibrosis. The frequency of co-occurrence, the temporal order of acquisition and clonal relationship of these alterations is poorly understood, and it is also unclear for this case since there is no prior bone marrow biopsy or diagnostic work up. Literature search of these rare cases show that some patients with similar findings progress to myelofibrosis as in this patient. It is possible that the presence of two mutated tyrosine kinase genes accelerates disease progression.

Utility of Targeted Next Generation Sequencing (NGS) to Predict Hematologic Neoplasms with Germline Predisposition

Abstract Introduction/Objective Hematologic neoplasms with germline predisposition are increasingly gaining clinical relevance as associated gene variants are emerging. These variants confer an increased risk for developing hematologic neoplasms as additional somatic aberrations accumulate. Recognition of germline predisposition is crucial to patient management as it would prompt genetic counseling and regular surveillance in affected patients and biological family members, as well as guide therapy, as many patients undergo allogeneic stem cell transplantation for which relatives are typically the preferred donors. Furthermore, these patients may respond differently to conventional therapies. Clinical recognition of germline predisposition is challenging due to phenotypic heterogeneity and a lack of germline testing standards and resources. Next generation sequencing is routinely utilized to detect somatic variants associated with hematopoietic neoplasms. Molecular profiling may also potentially serve as a screening tool to suggest pathogenic germline variants. Methods/Case Report Comprehensive genomic profiling data was reviewed for 301 patients with known hematologic neoplasms. A somatic-germline-zygosity (SGZ) computational method classified variants by origin. Variants of unknown clinical significance were excluded. The final study showed 94 patients predicted to have germline variants. The variables analyzed include germline variants, concurrent mutations, diagnosis, sex, age, and ancestry. Results (if a Case Study enter NA) Acute myeloid leukemia was the most frequent diagnosis, followed by B-cell acute lymphoblastic leukemia, myeloproliferative neoplasms, myelodysplastic syndrome, and chronic myelomonocytic leukemia. The median patient age was 60 years, ranging from 6 months to 91 years. Male gender and European ancestry were proportionally greater. In this study, we identified 70 distinct genes with 145 germline pathogenic variants. The most common pathogenic germline variants were TET2, SRSF2, RUNX1, DNMT3A, and CHEK2. Conclusion In conclusion, SGZ computational methods can be used as a screening tool to predict possible germline mutations in hematologic malignancies, which will help guide treatment and improve patient and family outcomes

Case Series: Unveiling mass-forming neoplastic extramedullary hematopoiesis in chronic myeloid leukemia

Abstract Introduction/Objective Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm characterized by BCR::ABL1 fusion and predominantly granulocytic proliferation. Three main phases of disease have previously been recognized: chronic, accelerated and blast phase, though accelerated phase has become controversial. During the chronic phase, leukemic cells exist predominantly in the peripheral blood and bone marrow; however, during blast phase, blasts can proliferate in the blood, bone marrow, or extramedullary tissues. Methods/Case Report We present two instances of cutaneous extramedullary hematopoiesis associated with CML at our institution. Results (if a Case Study enter NA) Case 1: A 34-year-old man previously diagnosed with CML presented with painful pustules on his right thigh. Biopsy revealed an infiltration of primarily left-shifted granulocytes, along with scattered megakaryocytes, and rare erythroid precursors. Immunohistochemical studies were consistent with maturing extramedullary hematopoiesis, devoid of sheets or clusters of blasts. Peripheral blood analysis revealed marked neutrophilic leukocytosis with basophilia and eosinophilia. Bone marrow examination depicted left-shifted granulocytic hyperplasia, megakaryocytic hyperplasia, and fewer than 5% blasts. Case 2: A 40-year-old man presented with fatigue, night sweats, weight loss, hepatosplenomegaly and palpable nodules on his left arm and thighs. The biopsy of the thigh nodule uncovered leukemic cells at different developmental stages, along with eosinophils, erythroid precursors, and megakaryocytes. Immunohistochemical staining confirmed their presence, with only a few blasts observed. Blood and bone marrow tests showed leukocytosis with blasts less than 5%, indicating CML in the chronic phase. Molecular analysis confirmed BCR-ABL1 fusion. Conclusion Mass-forming neoplastic extramedullary hematopoiesis in the skin during chronic phase of CML is a feature that is not well-documented in the literature. This entity shows immature granulocytic precursors, but does not exhibit an increase in blasts and therefore should not be called leukemia cutis or myeloid sarcoma. It is important to raise awareness of this entity to prevent misinterpretation as myeloid sarcoma and subsequent unnecessarily aggressive therapy.