Leukemia Cutis Research Articles

Acute Lymphoblastic Leukemia Presenting With Skin Rash And Forehead Swelling In A 31-Year-Old Male

Leukemia cutis is the infiltration of neoplastic leukocytes or their precursors into the epidermis, the dermis, or the subcutis of patients with leukemia, resulting in clinically identifiable cutaneous lesions. It is especially rare as the presenting symptom of leukemia and is associated with a poor prognosis. We present a case of acute lymphoblastic leukemia, whose initial complaints were skin lesions and forehead swelling, which we believe to be features of leukemia cutis. J Dhaka Med Coll. 2023; 32(1) : 96-98

Diagnostic approach to leukemia cutis : A differential diagnostic step-by-step algorithm.

Leukemia cutis is a conflicting term to describe neoplastic hematopoietic infiltrates in the skin. Cutaneous myeloid or lymphoid proliferations often present a serious differential diagnostic challenge for pathologists. This review aims to outline the confusion associated with the term leukemia cutis and discuss in detail the foremost common differential diagnoses in daily practice. The review is based on a summary of the relevant literature as well as on the authors' experience. It addresses precursor cell myeloid and lymphoid tumors that are strictly considered true leukemia cutis but also more mature neoplasms, including some recently described mature extramedullary myeloid proliferations. Finally, a practical, comprehensive stepwise approach combining traditional immunohistochemical marker panels, novel lineage- or mutational-specific markers, and other ancillary tests is suggested to reach an entity-specific diagnosis. The proper combination of ancillary techniques can help the pathologist to provide an accurate diagnosis of these challenging skin lesions.

A case of isolated cutaneous myeloid sarcoma preceding acute myeloid leukemia and literature review

Isolated Cutaneous Myeloid Sarcoma (icMS) and Aleukemic Leukemia Cutis (ALC) are cutaneous extramedullary manifestations of leukemia in which leukemic cells infiltrate the skin before they can be identified either in the peripheral blood or in the bone marrow. We report the case of a 67-year-old patient who presented with a rapidly developing cutaneous tumour and scaly, erythematous-squamous plaques. Isolated Cutaneous Myeloid Sarcoma was diagnosed which rapidly progressed to terminal-stage Acute Myeloid Leukemia (AML). To highlight the disease characteristics of the adult-onset icMS and ALC cases that preceded AML we additionally compiled the pertinent literature of case reports of these rare conditions. We identified n=15 previously published icMS/ALC cases with adequately detailed clinical data descriptions. We could confirm the medical experience that icMS/ALC patients have an overall worse prognosis. Moreover, we could identify FAB M5 AML subtype as a significant adverse prognosticator of these patients.

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.

Rare Clinical Symptoms in Hairy Cell Leukemia: An Overview.

Hairy cell leukemia (HCL) is a rare indolent B-cell lymphoid malignancy. The majority of patients are asymptomatic and HCL is usually diagnosed incidentally during a routine blood cell count. In symptomatic patients, typical symptoms are related to pancytopenia and splenomegaly. In this review, we present rare clinical symptoms in patients with HCL. A literature search was conducted of PubMed, Web of Science and Google Scholar for articles concerning hairy cell leukemia, leukemia cutis, bone lesions, neurological manifestations, pulmonary symptoms, ocular manifestations, cardiac manifestation and rare symptoms. Publications from January 1980 to August 2024 were scrutinized. Additional relevant publications were obtained by reviewing the references from the chosen articles. Extramedullary and extranodal manifestations of classic HCL are rare. However, leukemic involvement in the skin, bone, central nervous system, gastrointestinal tract, heart, kidney, liver, lung, ocular system and other organs have been reported.

53769 Genetic profiles and associated survival of leukemia cutis in patients with acute myeloid leukemia

53769 Genetic profiles and associated survival of leukemia cutis in patients with acute myeloid leukemia

Myeloid sarcoma, spectrum of clinical characteristics, prognostic impact, and treatment outcome

BackgroundAcute leukemia may present with extramedullary (EM) tissues. Myeloid sarcoma (MS) and leukemia cutis (LC) are considered extramedullary diseases. This study aims to evaluate the incidence, clinical characteristics, and prognostic factors affecting the outcome of pediatric patients with myeloid sarcoma at the pediatric oncology center from July 2007 to December 2017. Radiological imaging was used to stage the tumor, biopsy was done for pathological diagnosis, and bone marrow aspirate for morphology, flow cytometry, cytogenetics, and molecular analysis. Patients received chemotherapy protocols based on those used by the Children's Cancer Group for acute myeloid leukemia (AML).ResultThe study included 91 (13.2%) of 687 pediatric patients with acute myeloid leukemia, with a male-to-female ratio of 1.9 to 1. Prognostic factors that improved the patient’s 5-year overall survival (OS) were age > 5 years old, molecular and cytogenetic detection of t (8; 21), inv 16, presence of a single and small size lesion < 5 cm, negative CNS lesion, and achieved radiological response in isolated disease or radiological and marrow complete remission in disseminated disease post induction 1 with significant P value. Relapse, particularly early relapse, worsens the OS and EFS by 10% and 7.7%, respectively.ConclusionPatients over five with low-risk disease based on cytogenetics, a small, single, negative CNS lesion, and a complete response post induction 1 had better outcomes, with no significant difference between those with isolated extramedullary disease and those with marrow dissemination. Early relapse harms the outcome. The study group’s 5-year OS and EFS rates are 51.4% and 49.4%, respectively.

Aleukemic leukemia cutis: a rare case report

Leukemia cutis is a rare case disorder characterised by infiltration of neoplastic leukocytes (myeloid or lymphoid) in clinically identifiable cutaneous lesions. It can occur before the onset of hematological presentation of leukemia or during the disease course. The lesions may be highly variable ranging from flesh coloured to violaceous papules, nodules or plaques. A 52-year-old male patient came to the Dermatology Department with multiple asymptomatic erythematous papulonodular lesions involving the face, trunk as well as the extremities from the past 6 months. Systemic examination and counts were normal. On histopathological examination diffuse dense infiltrate of neutrophils and eosinophils throughout the dermis with extension of infiltrate in the interstitium of reticular dermis. Scattered amidst the infiltrate were several large cells with abundant pale cytoplasm and irregular nuclei. Immunohistochemistry was done, radiotherapy was planned and poor prognosis was explained to the patient. The case is being reported due to its rarity and the role of dermatopathologist in early diagnosis.

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

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. 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 6months of life with cEMD or AML-cEMD. Descriptive statistics, Fisher's exact test, Kaplan-Meier method, and log rank test were applied. 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. 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.

CLO24-060: Organomegalies as a Predictive Indicator of Leukemia Cutis in the Patients With Acute Myeloid Leukemia.

CLO24-060: Organomegalies as a Predictive Indicator of Leukemia Cutis in the Patients With Acute Myeloid Leukemia.

Chronic myelomonocytic leukemia: 2024 update on diagnosis, risk stratification and management.

Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic stem cell disorder with overlapping features of myelodysplastic syndromes and myeloproliferative neoplasms, characterized by prominent monocytosis and an inherent risk for leukemic transformation (~15%-20% over 3-5 years). Newly revised diagnostic criteria include sustained (>3 months) peripheral blood (PB) monocytosis (≥0.5 × 109/L; monocytes ≥10% of leukocyte count), consistent bone marrow (BM) morphology, <20% BM or PB blasts (including promonocytes), and cytogenetic or molecular evidence of clonality. Cytogenetic abnormalities occur in ~30% of patients, while >95% harbor somatic mutations: TET2 (~60%), SRSF2 (~50%), ASXL1 (~40%), RAS pathway (~30%), and others. The presence of ASXL1 and DNMT3A mutations and absence of TET2 mutations negatively impact overall survival (ASXL1WT/TET2MT genotype being favorable). Several risk models serve similar purposes in identifying high-risk patients that are considered for allogeneic stem cell transplant (ASCT) earlier than later. Risk factors in the Mayo Molecular Model (MMM) include presence of truncating ASXL1 mutations, absolute monocyte count >10 × 109/L, hemoglobin <10 g/dL, platelet count <100 × 109/L, and the presence of circulating immature myeloid cells; the resulting 4-tiered risk categorization includes high (≥3 risk factors), intermediate-2 (2 risk factors), intermediate-1 (1 risk factor), and low (no risk factors); the corresponding median survivals were 16, 31, 59, and 97 months. CMML is also classified as being "myeloproliferative (MP-CMML)" or "myelodysplastic (MD-CMML)," based on the presence or absence of leukocyte count of ≥13 × 109/L. ASCT is the only treatment modality that secures cure or long-term survival and is appropriate for MMM high/intermediate-2 risk disease. Drug therapy is currently not disease-modifying and includes hydroxyurea and hypomethylating agents; a recent phase-3 study (DACOTA) comparing hydroxyurea and decitabine, in high-risk MP-CMML, showed similar overall survival at 23.1 versus 18.4 months, respectively, despite response rates being higher for decitabine (56% vs. 31%). These include systemic inflammatory autoimmune diseases, leukemia cutis and lysozyme-induced nephropathy; the latter requires close monitoring of renal function during leukocytosis and is a potential indication for cytoreductive therapy.

Organomegalies as a predictive indicator of leukemia cutis in patients with acute myeloid leukemia.

Leukemia cutis (LC) is an extramedullary acute myeloid leukemia (AML) infiltrate. No previous study has described the clinical characteristics and outcomes of Thai patients diagnosed with AML with LC. We conducted a 7-year retrospective case-control study on Thai AML patients at Siriraj Hospital from November 2013 to July 2020. Patients were divided into LC and non-LC groups. Initial clinical presentations and laboratory findings were examined to identify LC-associated factors. Overall survival (OS) and relapse-free survival (RFS) were assessed. Pathological tissues underwent re-evaluation to validate the LC diagnoses. The study included 159 patients in a 2:1 ratio (106 non-LC and 53 LC). The LC group had a mean ± SD age of 54.3 ± 15.5 years; females were predominant. Three-fifths of the LC patients had intermediate-risk cytogenetics; 20.4% had an adverse risk, and 10.2% had a favorable risk. Most were classified as AML-M4 and AML-M5. Leukemic nodules were the primary finding in 58.5% of the cases, mainly on the legs. In the multivariate analysis of predictive factors associated with LC, organomegalies, specifically hepatomegaly, and lymphadenopathy, remained significant factors associated with LC [OR 4.45 (95%CI 1.20, 16.50); p = 0.026 and OR 5.48 (95%CI 1.65, 18.20); p = 0.005], respectively. The LC group demonstrated a significantly reduced OS (log-rank test p = 0.002) (median OS of 8.6 months vs. 32.4 months). RFS was considerably lower in the LC group (log-rank test p = 0.001) (median duration of 10.3 months vs. 24.4 months in the non-LC). AML patients who developed LC tended to experience notably poorer prognoses. Therefore, it is imperative to consider aggressive treatment options for such individuals. The presence of organomegalies in AML patients serves as a strong predictor of the possible occurrence of LC when accompanied by skin lesions.

Aleukemic congenital leukemia cutis preceding monocytic leukemia with favorable outcome: A case report.

A newborn girl had typical "blueberry muffin" skin lesions, which shows histopathologic features of monocytic leukemia cutis. The systemic leukemia was demonstrated after one month of life. She was treated by chemotherapy, including induction and three consolidation cures, according to the ELAM02 protocol, which led to complete remission. This case report with congenital form of AML5 cutaneous localization, preceding systemic involvement, with a 5-year follow-up and positive outcome is remarkable.

Cutaneous manifestations of myelodysplastic syndrome: A systematic review.

Myelodysplastic syndrome (MDS) may present with specific skin lesions, such as leukaemia cutis, which is a well known poor prognostic marker of leukaemia with a high risk of acute leukaemic transformation. However, less is known regarding non-specific cutaneous manifestations of MDS including the prevalence, types and their prognostic and therapeutic significance, which we aimed to determine through this systematic review. We searched electronic databases (PubMed, Medline and EMBASE) from inception up to 26 January 2023 for studies reporting cutaneous manifestations of MDS. Eighty eight articles (case reports n=67, case series n=21), consisting of 134 patients were identified. We identified 6 common cutaneous manifestations: neutrophilic dermatoses (n=64), vasculitis (n=21), granulomatous (n=8), connective tissue disease (CTD) (n=7; composed of dermatomyositis (n=5), cutaneous lupus erythematosus (n=1), and systemic sclerosis (n=1)), panniculitis (n=4), immunobullous (n=1), and other (n=29). Cutaneous features either occurred at time of MDS diagnosis in 25.3%, preceding the diagnosis in 34.7% (range 0.5-216months), or after diagnosis in 40.0% (range 1-132months). Prognosis was poor (40.2% death) with 34.1% progressing to acute myeloid leukaemia (AML). 50% of those with MDS who progressed to AML had neutrophilic dermatoses (p=0.21). Myelodysplastic syndrome was fatal in 39.2% of neutrophilic dermatoses (median time from onset of cutaneous manifestation: 12months), 50% of vasculitis (7.5months), 62.5% of granulomatous (15.5months) and 14.3% of CTD (7months). Recognition of patterns of cutaneous features in MDS will improve early diagnosis and risk stratification according to subtype and associated prognosis.

P19 Spontaneous regression of aleukaemic cutis leukaemia in a male infant

Abstract Introduction Congenital leukaemia is a rare haematologic disease presenting in the first 4-6 weeks of life. Affected children may present with systemic symptoms of fever, hepatosplenomegaly and skin infiltration in the form of leukaemia cutis. Prognosis is generally poor but some cases of spontaneous regression have been described. We report a case of a 5-week-old who had biopsy confirmed cutis leukaemia which went on to resolve spontaneously. Case A male infant developed widespread erythematous/violaceous patches and nodules in the first week of life. He remained systemically well. A skin biopsy at 5 weeks of age showed features of a malignant haematological infiltrate, favouring a myeloid/monocytic leukaemic process. Baseline bloods were normal including a blood film which did not show any evidence of blasts. Interestingly, following his biopsy, skin lesions began to improve with complete resolution of all skin lesions by six weeks of age. RNA fusion panel analysis of affected skin detected a PICALM::MLLT10 t(10;11) (p12;q14) fusion which is a rare but recurrent finding in acute lymphoblastic leukaemia . He continues monthly haematology surveillance and has remained disease free at 8 months. Conclusion Spontaneous regression of aleukaemic leukaemia cutis is a rare phenomenon. Patients require close ongoing surveillance as some may relapse with systemic disease after several years. Key to management of this case was prompt suspicion of leukaemia cutis and biopsy which enabled an accurate diagnosis despite the brief window of skin lesions and has subsequently enabled accurate genotyping and future rigorous surveillance in this child.

Herpes Zoster Granulomatous Dermatitis: A Rare but Memorable Complication

There have been reports of benign and cancerous cutaneous reactions developing at the site of resolved herpes zoster weeks to years after the acute infection. This case study describes a 71-year-old male patient with herpes zoster granulomatous dermatitis, a manifestation of postherpetic isotopic response. His medical history was significant for Graves' disease and chronic myelomonocytic leukemia. After presenting to the emergency department, he was diagnosed with herpes zoster generalisatus. Approximately two months after receiving treatment for herpes zoster, multiple firm subcutaneous nodules appeared on his neck. An excisional biopsy was performed to rule out leukemia cutis. The specimen displayed extensive dermal lymphohistiocyte infiltration, marked by central necrosis and atypical T cells. Tests for tuberculosis and leukemia were negative. At follow-up, an excisional biopsy of the recurrent neck nodules confirmed diffuse dermal infiltration and central necrosis. Based on the clinical and pathological findings, he was diagnosed with herpes zoster granulomatous dermatitis. He was administered systemic and topical steroid therapy over one month, after which the lesions and associated symptoms improved. Wolf's isotopic response refers to the occurrence of a new skin disease at the site of an already healed, unrelated skin disease. This phenomenon is frequently overlooked—especially following herpes zoster. Healthcare practitioners should know Wolf's isotopic response to ensure accurate diagnosis and avoid potential oversight of malignant diseases.

Leukemia cutis: a rare manifestation of an underlying primary plasma cell leukemia

Leukemia cutis: a rare manifestation of an underlying primary plasma cell leukemia

Infantile B-cell acute lymphoblastic leukaemia with the highest recorded count of white blood cells in the literature: case report and literature review

Introduction: Infantile leukaemia is an uncommon haematological cancer that manifests within the first year of life. This malignancy is highly aggressive and possesses distinctive immunophenotypic, cytogenetic, and molecular attributes. It can originate from either myeloid or lymphoid cells. It often exhibits a higher incidence among females. Case presentation: A 1-month-old male infant, initially seemingly healthy, presented with irritability and feeding difficulties. Born without complications, routine neonatal assessments appeared normal, and physical examination revealed no abnormalities. However, laboratory tests indicated an extremely high white blood cell count, low platelets, and elevated haemoglobin. Further examinations showed a white blood cell count of 1450 × 106/l with a blood film revealing significant leukocytosis dominated by blast cells. Abdominal ultrasound confirmed hepatosplenomegaly which was not present during pregnancy. Subsequent bone marrow analysis and flow cytometry established a diagnosis of B-cell acute lymphoblastic leukaemia (B-ALL). Clinical discussion: It is rare for infantile ALL to manifest within the first month after birth. In most cases, the diagnosis is established before birth. When characteristic signs such as hepatosplenomegaly, leukaemia cutis, or infiltrative involvement of the extramedullary and central nervous systems are present, postnatal diagnoses are relatively straightforward. However, there are instances where children present with non-specific and ambiguous symptoms that resemble other medical conditions. Conclusion: This case underscores the importance of paediatricians being vigilant and attuned to the subtle indicators that differentiate common illnesses from serious conditions such as infantile ALL.

Protective Function of Human Skin Mesenchymal Niches for Acute Myeloid Leukemia-Initiating Stem Cells

Leukemia cutis (LC) or leukemic cell infiltration in skin is one of the common extramedullary manifestations in acute myeloid leukemia (AML) and signifies a poorer prognosis. However, the pathogenesis and maintenance of LC have been understudied, limiting our understanding of its impact on AML progression and relapse. We recently have shown that the AML cells infiltrated in the mouse skin during steady state and after chemotherapy were capable to regenerate AML after serial transplantation (Sandhow et al., J. Exp. Med, 2023). Further characterization of the skin mesenchymal stem cells (MSCs) suggests that skin MSCs could maintain AML-initiating stem cells (LSCs) and protect them from chemotherapy, even to a greater degree than their bone marrow (BM) counterparts. These data suggest the protective role of skin mesenchymal niche in AML LSCs during chemotherapy. However, it remains unexplored whether human skin MSCs exert the same functional impact on human AML cells. We here have explored the role of human skin MSCs in AML maintenance and survival during chemotherapy by RNA sequencing and in vitro co-culture of patient-derived AML cells with primary human skin MSCs in comparison with BM MSCs. We first by prospective characterization identified human skin MSCs with a phenotype of CD45-CD235a-CD31-CD44+CD146- from healthy donors. RNA sequencing and Q-PCR revealed expression of key hematopoietic stem cell (HSC) regulatory genes including THPO, SCF, CXCL12 and LAMA4 in human skin MSCs. Interestingly, while HSC maintenance genes such as THPO and KITLG were significantly upregulated in skin MSCs (p&amp;lt;0.0001 and p&amp;lt;0.05, respectively), HSC negative regulator SPP1 was downregulated (p=0.05), pointing to a possible better hematopoiesis-supportive function of skin MSCs. In line with this, our functional studies indicated that skin MSCs displayed a superior protective effect on human AML cell line THP-1 than their BM cell counterparts during cytarabine (Ara-C) treatment in the in vitro co-culture. There were more residual chemo-resistant AML cells, reflected in the higher number of CD36+ AML cells after treatment with Ara-C in cocultures with skin MSCs, compared to that with BM MSCs (p=0.0065). This result was confirmed by functional assays showing the increased number of cobblestone area-forming cells (p=0.0298) and colony-forming units (p=0.038) within the residual AML cells co-cultured with skin MSCs. To investigate the mechanisms involved in the protective function of human skin MSCs, we have performed RNA-sequencing of the human skin and BM MSCs before and after co-culture with AML cells. This has revealed potential unique molecular pathways between AML and skin MSCs. Furthermore, there were dramatically less altered genes in the skin MSCs compared to BM MSCs after 3 day-coculture with THP1 AML cells (221 vs 1761 altered genes with adjusted p values &amp;lt;0.05). These data indicate that skin MSCs are likely more resistant to AML-remodeling, which could in turn maintain AML cells in quiescence status, thereby protecting AML cells from Ara-C treatment. This speculation is currently under validation. In addition, gene set enrichment analysis showed upregulated genes associated with fatty acid metabolisms and ribosome in skin MSCs compared to BM MSCs, providing molecular evidence for a potential better metabolic support of skin MSCs for AML cells. Taken together, our preliminary data indicate an important role of human skin MSCs in supporting and protecting AML cells during Ara-C treatment. We are further investigating the underlying mechanisms.

Leukemia Cutis-The Current View on Pathogenesis, Diagnosis, and Treatment.

Leukemia cutis (LC) is defined as the leukemic infiltration of the epidermis, the dermis, and the subcutaneous tissue. Leukemia cutis may follow or occur simultaneously with the diagnosis of systemic leukemia. However, cutaneous lesions are occasionally diagnosed as the primary manifestation of leukemia. Leukemic skin infiltrations demonstrate considerable variation regarding a number of changes, distribution, and morphology. The highest incidence of LC is observed in chronic lymphocytic leukemia, monocytic and myelomonocytic acute myeloid leukemia, and T-cell lineage leukemia. Although the pathogenic mechanism of the invasion of leukemic cells into the skin is not well understood, chemokine receptors and adhesion molecules as well as the genetic characteristics of leukemia are thought to play a role. Leukemic skin lesions may be localized or disseminated and may occur alone or in combination on any site of the skin, most frequently in the trunk and extremities. The most common clinical presentations of leukemia cutis are papules, nodules, macules, plaques, and ulcers. In most patients, the complete or partial resolution of cutaneous infiltrations occurs simultaneously with hematologic remission. However, in patients with resistant disease or recurrent skin infiltration, local radiotherapy can be used. This review presents recent data on the pathogenesis, diagnosis, and treatment of leukemic skin involvement in different types of leukemia.