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.

Blasts with folded nuclei: A histopathologic finding in myeloid leukemia cutis with NPM1 and FLT3 mutations.

Leukemia cutis is a term used to describe cutaneous manifestations of leukemic infiltration of the skin and portends a poor prognosis. Cutaneous involvement by hematopoietic/lymphoid tumors can occur before, concurrently, or after the initial diagnosis. Early involvement of dermatologists and timely biopsies play a crucial role in achieving a prompt diagnosis. Prior reports of acute myeloid leukemia have revealed a strong association between the cup-like nuclear morphology observed in bone marrow specimens and concurrent mutations of NPM1 and FLT3-ITD. In cutaneous tissue sections of leukemia cutis, folded or indented nuclei may represent the "cup-like" counterpart previously described in bone marrow specimens. Recognizing this morphological feature could aid in identifying this molecular subtype of leukemia cutis. In this study, we present a case of leukemia cutis in a 63-year-old female with AML and NPM1 and FLT3-ITD mutations, demonstrating scattered indented/folded nuclei.

The evolving role of reduced-dose total skin electron beam therapy in skin malignancies: the renaissance of a rare indication.

Definitive radiation therapy is an effective local treatment for several cutaneous malignancies. Patients with diffuse or generalized skin manifestations might require total skin electron beam therapy (TSEBT) as an alternative treatment to the chasing technique. In this short communication, we highlight the evolving role of TSEBT and present its role in various forms of skin malignancies.

Acute Myeloid Leukemia with NPM1 Mutation and Disseminated Leukemia Cutis: Achievement of Molecular Complete Remission by Venetoclax/Azacitidine Combination in a Very Old Patient.

We describe a case of acute myeloid leukemia with NPM1 mutation and disseminated leukemia cutis in a very old patient, who achieved a long-lasting response to the azacitidine/venetoclax combination with molecular complete remission, given the potential value of this rarely observed clinical outcome.

IRF8 may be a useful marker for blastic plasmacytoid dendritic cell neoplasm, especially with weak CD123 expression.

We highlight the utility of interferon regulatory factor 8 (IRF8), a novel marker of monocytic and dendritic cell lineages, in the diagnosis of a case of blastic plasmacytoid dendritic cell neoplasm (BPDCN) presenting initially in the skin. A 60-year-old male with a previous history of myelodysplastic syndrome presented with cutaneous nodules on chest and scalp. A punch biopsy specimen of a skin nodule showed a diffuse dermal infiltrate of atypical mononuclear cells. The neoplastic cells expressed CD4, CD56, CD43, and TdT but showed minimal reaction for TCL-1 and CD123, and were negative for CD34, CD117, and MPO, confounding the diagnosis. IRF8 performed in retrospect was strongly positive. A new punch biopsy specimen of a chest nodule showed the blastoid tumor cells were positive for TCL-1, CD4, and CD56, but dim CD123. Subsequent bone marrow involvement showed blastoid tumor cells with intense positivity for CD123, CD4, and CD56, which was supportive of the BPDCN diagnosis. BPDCN cases with weak or variable CD123 and TCL-1 expression represent a potential diagnostic pitfall. In a recent study, 15 cases of BPDCN showed uniformly strong staining for IRF8, while CD123 was dim or negative in 4 of these 15 cases. We suggest IRF8 may be a useful marker for BPDCN, especially in cases with weak or variable expression of CD123 and TCL1.

A case of aleukemic leukemia cutis after COVID-19 infection presenting as facial rash.

Aleukemic leukemia cutis (ALC) is a rare condition that is characterized by leukemic cells in the skin before presenting in the peripheral blood or bone marrow. We report a case of a 43-year-old woman who underwent assessment for bilateral facial nodules arising 1 month after COVID-19 infection. A punch biopsy specimen showed a malignant neoplasm primarily composed of immature blasts dissecting through the collagen in the dermis, concerning for myeloid sarcoma versus leukemia cutis. Bone marrow and blood specimens were negative for hematologic malignancy. The patient was appropriately treated with chemotherapy and is recovering well. This report highlights an interesting case of ALC following COVID-19 infection presenting as an isolated facial rash. Whether there is a true relationship between the patient's COVID-19 infection and her abrupt presentation of leukemia remains unclear, but we present this case regardless, in an effort to highlight a potentially unique association requiring further study.

Molecular annotation of extramedullary acute myeloid leukemia identifies high prevalence of targetable mutations.

BACKGROUND: Genomic landscape of extramedullary acute myeloid leukemia (EM-AML), including myeloid sarcoma (MS) and leukemia cutis (LC), is not well characterized. The potential utility of next-generation sequencing (NGS) using EM tissue is not established. METHODS: In this multicenter retrospective study, clinical and NGS data were collected on patients with EM-AML. All statistical analyses were performed in SPSS Statistics (v 26). RESULTS: Our study included 58 patients with EM-AML. The median age at diagnosis was 62 years; 59% of patients had MS and 33% had LC. EM-AML was isolated (i.e., without blood or marrow involvement) in 31% and was first noted at relapse in 60% of patients. Median overall survival in our cohort was 18.2 months overall, with 19.1 months and 11.6 months in the newly diagnosed and the relapsed/refractory patients, respectively. At least one targetable or potentially targetable alteration was present in 52% of patients with EM-site NGS, with 26% IDH1, 21% NPM1, 11% IDH2, 6% FLT3, and 13% KMT2A-PTD. Mutations in IDH1 were significantly more prevalent on NGS from EM tissue than non-EM (blood or marrow) samples (26% vs. 3%; p = .030). Three of four patients treated with IDH inhibitors based on EM-site NGS experienced a complete response. CONCLUSIONS: Targetable mutations are frequent in EM-AML and EM-site NGS is warranted for selecting potential targeted therapies for patients with EM-AML.

Primary cutaneous gamma-delta T-cell lymphoma masquerading as leukemia cutis in a patient recently diagnosed with small lymphocytic lymphoma: Clues to the diagnosis.

A 54-year-old man recently diagnosed with small lymphocytic lymphoma (SLL) had waxing and waning, indurated, erythematous plaques on his legs, with leukopenia and anemia disproportionate to the SLL burden in his marrow and pelvic lymph nodes. Punch biopsy of a plaque performed to evaluate for leukemia cutis revealed a lymphocytic lobular-panniculitis-like infiltrate resembling lupus panniculitis, but a preponderance of CD8+/Ki-67+ T-cells surrounding adipocytes raised concern for subcutaneous panniculitis-like T-cell lymphoma (SPTCL). Additional immunohistochemistry (IHC) studies showed that the adipotropic T-cells expressed TCR-gamma, supporting the rare, unexpected diagnosis of Primary cutaneous gamma-delta T-cell lymphoma (PCGDTCL). The patient subsequently met diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH). PCGDTCL is an aggressive, HLH-associated lymphoma requiring different management than SPTCL and SLL. This case illustrates how PCGDTCL can co-exist with B-cell lymphoma and resemble panniculitis on biopsies. PCGDTCL and SPTCL should enter the differential diagnosis whenever patients present with the constellation of lobular panniculitis and unexplained cytopenias. In the present case, close clinicopathologic correlation and judicious use of IHC on a small sample allowed for a prompt diagnosis.

Pediatric Cutaneous Hematologic Disorders: Cutaneous Lymphoma and Leukemia Cutis-Experience of a Tertiary-Care Pediatric Institution and Review of the Literature.

BACKGROUND: Cutaneous hematologic malignancies are rare in children, and the literature about them is still sparse. OBJECTIVE: The purpose of our study was to report our experience with pediatric cases of cutaneous hematologic disorders and describe their clinical and histological features. METHODS: Data were retrospectively collected from the histopathologic database of the CHU Sainte-Justine, University of Montreal, Montreal, Canada. All patients up to 18 years of age with a diagnosis of a primary cutaneous lymphoma (including lymphomatoid papulosis), secondary cutaneous lymphoma or cutaneous manifestations of leukemia, followed from 1980 to 2019 at our center were reviewed. RESULTS: Thirty-six patients were included. Age at presentation ranged from birth to 18 years of age (mean 7.83 ± 5.16; median 7.0). Ten different hematologic disorders were identified according to the WHO-EORTC classifications: lymphomatoid papulosis (10 cases), mycosis fungoides (6 cases), anaplastic large cell lymphoma (4 cases), pre-B acute lymphoid leukemia (5 cases), primary cutaneous marginal zone B-cell lymphoma (4 cases), primary cutaneous CD4+medium T-cell lymphoproliferative disorder (1 case), extranodal NK/T-cell lymphoma (1 case), hydroa vacciniforme-like lymphoproliferative disorder (1 case), B-cell lymphoblastic lymphoma (1 case) and acute myeloid leukemia (3 cases). CONCLUSION: The most common subtype of cutaneous hematologic disease in our single institution study was lymphomatoid papulosis (type A and type C), followed by mycosis fungoides. Recognition of this large clinical and histological spectrum by dermatologists is important because diagnosis is often established by biopsy of skin lesions, even in secondary cutaneous cases. Moreover, the clinicopathological correlation is of utmost importance for the final diagnosis of those pathologies.

Bilateral periorbital leukemia cutis presenting as suspected cellulitis.

Many conditions present with periorbital edema and erythema, mimicking preseptal cellulitis. We report the unique case of a patient with relapsed monoblastic mutant isocitrate dehydrogenase-2 (IDH2) acute myeloid leukemia (AML) who presented with periorbital edema and erythema, unresponsive to antibiotics. Histopathology from punch biopsy was consistent with leukemia cutis. The patient responded rapidly to the initiation of enasidenib, a novel targeted inhibitor of mutant IDH2 enzymes. Our case highlights the importance of considering leukemia cutis in patients with a history of leukemia presenting with periorbital edema and erythema.

Skin changes in hairy cell leukemia.

Skin lesions have been reported in about 10-12% of hairy cell leukemia (HCL) patients. Most are etiologically related to autoimmune or infectious processes, although secondary cutaneous neoplasms and drug-induced lesions are also reported. However, leukemia cutis with the direct infiltration of the skin by leukemic cells is extremely rare in HCL patients. This paper reviews the epidemiology, pathogenesis, clinical symptoms, diagnosis, and approach to treating skin lesions in HCL. A literature review of the MEDLINE database for articles in English concerning hairy cell leukemia, skin lesions, leukemia cutis, adverse events, infectious, cutaneous, drug reactions, neutrophilic dermatoses, secondary neoplasms, and vasculitis was conducted via PubMed. Publications from January 1980 to September 2020 were scrutinized. Additional relevant publications were obtained by reviewing the references from the chosen articles.

Chronic myeloid leukemia-leukemia cutis mimicking a neutrophilic panniculitis-like leukemia cutis: Report of a rare case.

While drug-induced panniculitis is not uncommon in chronic myeloid leukemia (CML) patients on tyrosine kinase inhibitor therapy, it is rare for CML to initially present as a leukemic panniculitis. We present the case of a 45-year-old male with no relevant prior medical history presenting with 6 months of migratory nodules, 2 months of drenching night sweats, and a 20 pound weight loss. Physical examination showed firm subcutaneous nodules with overlying ecchymoses present on the right lateral thigh and left lower back. Biopsy of a nodule from the right thigh showed a subcutaneous lobular panniculitis involved by a dense infiltrate of neutrophils and granulocyte precursors. Fluorescent in-situ hybridization (FISH) was positive for t(9;22)(q34;q11.2)BCR-ABL1 fusion. A concurrent hemogram revealed a white blood cell count elevation of 600,000 K/µL. Bone marrow biopsy examination showed marked myeloid expansion with an increase in granulocyte precursors and Philadelphia chromosome positivity by FISH, consistent with bone marrow involvement by CML. Herein, we describe this unusual and rare case of CML initially presenting as a neutrophilic panniculitis-like leukemia cutis. Arriving at this challenging diagnosis may be easily missed without clinical and laboratory correlation, which would certainly lead to the patient's not receiving life-saving treatment.

Shapiro xanthogranuloma: An essential diagnosis for dermatologists and dermatopathologists to recognize to avoid misdiagnosis of a hematopoietic malignancy in infants and neonates.

The Shapiro xanthogranuloma is a histopathologic form of xanthogranuloma that shows closely packed monomorphous cells, which can extend into the subcutaneous fat; it usually lacks routine diagnostic features of xanthogranuloma. Herein we describe two cases of Shapiro xanthogranuloma occurring in a neonate and in an infant, which were initially thought to be hematologic malignancies. One patient's presentation as a "blueberry muffin baby" added to the diagnostic confusion. Pediatric dermatologists, dermatologists, and dermatopathologists need to be aware of the Shapiro xanthogranuloma and its clinicopathologic features to avoid misdiagnosis of a hematopoietic malignancy in neonates and infants.

Case and review: Cutaneous involvement by chronic neutrophilic leukemia vs Sweet syndrome- A diagnostic dilemma.

Chronic neutrophilic leukemia (CNL) is a rare leukemia with approximately 150 total cases reported. Cutaneous neutrophilic infiltrates, including Sweet syndrome (SS) and leukemia cutis (LC), have been reported in six patients with CNL. In the setting of CNL, these two conditions are difficult to differentiate due to clinical and histopathological similarities, but it is important to do so because LC is associated with a worse prognosis. In general, SS is distinguished by its tenderness, fever, and improvement with steroids (vs chemotherapy for LC). Biopsy of LC reveals immature leukocytes, whereas SS shows almost exclusively mature leukocytes, but morphology alone may not be sufficient in some cases. Here, we report a case of a 72-year-old male with CNL and a cutaneous eruption with clinical and pathological features which made the distinction between the two diseases difficult.

Leukemia cutis in a medical center in southern Taiwan: A retrospective study of 42 patients.

BACKGROUND/PURPOSE: Leukemia cutis (LC), by definition, is the infiltration of neoplastic leukocytes in the skin. The overall incidence of LC is rare. We aimed to investigate the association between clinical characteristics, classifications and prognosis among different types of LC in Taiwan. METHODS: We performed a retrospective analysis of forty-two patients with histopathology proven LC based on skin biopsies in a medical center in Southern Taiwan from 1997 to 2018. The study involved medical records of the patients, clinical manifestations, and outcomes according to different types of leukemia. RESULTS: This series consisted of 27 males and 15 females, and the mean age was 55.7 years old. The most common cutaneous features were papules (38%) and nodules (29%), followed by plaques (16%) and ulcers (10%). The most commonly affected sites were the trunk (33%) and extremities (31.5%), although generalized distribution (14%) was not rare. The prognosis of LC was very poor, 76.2% of patients (32/42) died during the follow-up, and the median survival time was 7.2 months (95% CI, 4.53-9.87 months). No statistical significance was found (P = 0.068 for survival curves) among different types of LC. CONCLUSION: This study was the first large-scale research in regarding to LC of Han Chinese. The commonest clinical presentations were papules and nodules, and the predilection sites were trunk and extremities. Besides, there was the high frequency of LC from AML and MDS in Taiwan. Clinicians should pay more attention to the leukemia patients with extramedullary manifestations due to poor survival outcomes.

Differentiation syndrome during ivosidenib treatment with immunohistochemistry showing isocitrate dehydrogenase R132H mutation.

We report a case of differentiation syndrome in a patient receiving the IDH1 inhibitor ivosidenib, with skin biopsy showing isocitrate dehydrogenase (IDH) R132H-mutated leukemia cutis. A 72-year-old man with IDH1-mutated acute myeloid leukemia (AML), status-post allogeneic cell transplantation, on ivosidenib for 6 months, was admitted for culture-negative neutropenic fever, pink and purpuric plaques and patches on the legs, abdomen and back, edema, hypotension, and shortness of breath. Skin biopsy revealed an infiltrate of atypical, immature, myeloperoxidase-positive mononuclear cells compatible with leukemia cutis or Sweet syndrome. Although dermal edema and interstitial neutrophilic infiltrate with karyorrhexis characteristic of Sweet syndrome were not seen, the atypical cells lacked expression of CD117 and CD34, which were expressed in the original leukemia. Additional immunohistochemical staining of suspected blasts was strongly positive for IDH1 R132H, suggesting a diagnosis of leukemia cutis. As the immunophenotype of blasts in skin infiltrates can significantly differ from the immunophenotype seen in blood and bone marrow, this case shows that mutation-specific antibodies such as anti-IDH1 R132H may be useful to help distinguish malignant from non-malignant infiltrates in the skin. Furthermore, differentiation syndrome may show histopathologic features of leukemia cutis on skin biopsy.

Dermoscopic findings in neonatal leukemia cutis.

Leukemia cutis is the direct infiltration of cutaneous tissues by leukemic cells and can present as a blueberry muffin baby. We present a case of neonatal leukemia cutis highlighting its dermoscopic features, the presence of fine telangiectatic arborizing vessels distributed within a pink background within all lesions.

Pediatric leukemia cutis: A case series.

BACKGROUND: Pediatric leukemia cutis (LC) is often difficult to diagnose due to similarity in appearance to other dermatologic diseases. Several case reports and smaller case series have been published in the medical literature, but studies on larger cohorts of children with LC are lacking. OBJECTIVE: This study aimed to better characterize the clinical features, course, and prognosis of LC in the pediatric population. METHODS: We performed a retrospective case series of 31 patients diagnosed with LC at Boston Children's Hospital and the Children's Hospital of Philadelphia. RESULTS: The number and morphology of LC lesions varied among patients, with the head and lower extremities being the most common sites of involvement. Leukemia cutis presented concomitantly with systemic leukemia in the majority of cases. Most cases of LC arose during initial leukemia episodes, rather than with relapsed leukemia. Acute myeloid leukemia was the subtype most frequently associated with LC, followed by acute lymphoblastic leukemia. Diagnosis altered treatment timing and therapeutic decisions. CONCLUSION: Children most often present concomitantly with LC and systemic leukemia. Since the morphology and distribution of LC varies, physicians must maintain a high index of suspicion for this diagnosis, as the presence of LC may change the management of systemic leukemia.

Cutaneous presentation preceding acute myeloid leukemia with CD4+/CD56+ expression misdiagnosed as a blastic plasmocytoid dendritic cell neoplasm: A case report.

Acute myeloid leukemia (AML) may initially present as cutaneous lesions corresponding to blasts involving the skin as the first clinical manifestation prior to blood and bone marrow (BM) infiltration. Such presentation is known as myeloid leukemia cutis (LC). Blastic plasmocytoid dendritic cell neoplasm (BPDCN) is an aggressive tumor derived from the precursors of plasmocytoid dendritic cells with cutaneous and BM involvement and leukemic dissemination. Myeloid LC and BPDCN may be difficult to distinguish as they share similar clinical and histopathological features, in particular AML with monocytic differentiation. Nevertheless, the correct diagnosis has to be made to determine adequate and effective therapy. Here, we report the case of a 61-year-old woman who presented with an AML with MLL rearrangement and CD4+/CD56+ expression presenting as LC and that was misdiagnosed as BPDCN. We emphasize that careful and exhaustive analyses should be performed to make the correct diagnosis.

Pernio as the presenting sign of blast crisis in acute lymphoblastic leukemia.

A previously healthy 5-year-old girl presented with acute onset of blue toes and red spots on the nose and fingers. The striking nature of these lesions, along with the finding of submandibular lymphadenopathy, prompted further evaluation. Laboratory findings were remarkable for anemia, high transaminase levels, and high blast count. Histopathologic findings were consistent with early pernio. Further examination revealed acute B-cell lymphoblastic leukemia. Treatment of the leukemia led to resolution of the pernio.