Blastic Plasmacytoid Dendritic Cell Neoplasm

Blastic Plasmacytoid Dendritic Cell Neoplasm, from a Dermatological Point of View

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an aggressive hematological malignancy derived from the precursors of plasmacytoid dendritic cells. Although disease awareness has increased over time, BPDCN represents a rare disease with an aggressive clinical course and a dismal prognosis. Due to the overlap in clinical and histological features with a large spectrum of inflammatory and neoplastic diseases, BPDCN is difficult to diagnose. Furthermore, given the rarity of the disease, treatment options for BPDCN are limited, sometimes changing by practitioner and hospitals. Treatment options range from conventional chemotherapy to the recently approved biologic agent tagraxofusp and stem cell transplantation. Therefore, a multidisciplinary approach with coordination among dermatologists, pathologists, and hematologists is ultimately imperative to reach the correct diagnosis and management of BPDCN.

Low-dose venetoclax combined with azacitidine for blastic plasmacytoid dendritic cell neoplasm: a case report and literature review

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy that is highly aggressive with a poor prognosis. There is no standard treatment for BPDCN. Although conventional chemotherapies are usually sensitive in the initial therapy, relapse and drug resistance are inevitable within a short duration. Targeted therapies have enlightened new prospects for the treatment of BPDCN, especially for those in a frail state and intolerable to standard chemotherapies or hematopoietic stem cell transplantation. Here, we report an 82-year-old man diagnosed with cutaneous-limited BPDCN. Considering the old age and limited involvement of the tumor, we reduced the dosage of venetoclax. His skin lesions subsided significantly after 1 cycle of azacytidine (100 mg d1-7) combined with reduced doses of venetoclax (200 mg d1-14). The reduction in the dose of venetoclax avoided severe myelosuppression while achieving satisfactory outcomes. The patient received 2 cycles of therapy with no skin lesions re-occurred for 7 months before relapsing.

Treatment of patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN): focus on the use of tagraxofusp and clinical considerations

BPDCN is an aggressive myeloid malignancy with a poor prognosis. It derives from the precursors of plasmacytoid dendritic cells and is characterized by CD123 overexpression, which is seen in all patients with BPDCN. The CD123-directed therapy tagraxofusp is the only approved treatment for BPDCN; it was approved in the US as monotherapy for the treatment of patients aged ≥2 years with treatment-naive or relapsed/refractory BPDCN. Herein, we review the available data supporting the utility of tagraxofusp in treating patients with BPDCN. In addition, we present best practices and real-world insights from clinicians in academic and community settings in the US on how they use tagraxofusp to treat BPDCN. Several case studies illustrate the efficacy of tagraxofusp and discuss its safety profile, as well as the prevention, mitigation, and management of anticipated adverse events.

Unmet Clinical Needs and Management Recommendations for Blastic Plasmacytoid Dendritic Cell Neoplasm: A Consensus-based Position Paper From an Ad Hoc International Expert Panel

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a hematological malignancy characterized by recurrent skin nodules, an aggressive clinical course with rapid involvement of hematological organs, and a poor prognosis with overall survival. The rarity of the disease results in a few large-scale studies, a lack of controlled clinical trials for its management, and a lack of evidence-based guidelines. Here, we present a review of unmet clinical needs on the management of BPDCN by a panel of eleven experts involved in the research and clinical practice of BPDCN. Recommendations and proposals were achieved by multiple-step formalized procedures to reach a consensus after a comprehensive analysis of the scientific literature. The panel analyzed the critical issues of diagnostic pathway, prognostic stratification, therapy for young and fit patients and elderly and unfit patients, indication for allotransplant and for autotransplant, indication for central nervous system prophylaxis, and management of pediatric BPDCN patients. For each of these issues, consensus opinions were provided and, when appropriate, proposals for advancement in clinical practice were addressed. The hope is that this comprehensive overview will serve to improve the practice of BPDCN and inform the design and implementation of new studies in the field.

Patients with blastic plasmacytoid dendritic cell neoplasm in pregnancy: A rare case report

RATIONALE

Previous clinical reports of patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN) in pregnancy are rare.

PATIENT CONCERNS

The present study presents the case of 37-year-old women exhibiting third trimester with progressive painless, abdominal skin nodules.

INTERVENTIONS AND OUTCOMES

A 37-year-old pregnant woman with BPDCN and partial placenta previa and racket-shaped placenta. After comprehensive evaluation, the pregnancy status ends at 37 weeks and 6 days by cesarean section of lower uterus and no abnormality in the newborn.

LESSONS

Pregnant women diagnosed with BPDCN in the third trimester should terminate the pregnancy promptly for further treatment.

Clinical Insights into the Management of Blastic Plasmacytoid Dendritic Cell Neoplasm

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is aggressive hematologic malignancy derived from plasmacytoid dendritic cell precursors of myeloid cell lineage. Patients frequently present with bruise-like skin lesions, which typically are followed months later by progressive cytopenias. Historically, BPDCN prognosis has been dismal, with median overall survival ranging from 9 to 13 months. In the past 2 decades, our understanding of BPDCN pathogenesis has led to the successful development of novel therapeutics. In December 2018, the FDA approved tagraxofusp-erzs for adults and pediatric patients older than 2 years who have either treatment-naïve or relapsed/refractory BPDCN. Acute lymphoblastic leukemia (ALL)-based chemotherapy regimens also provide comparable outcomes to tagraxofusp. In our practice, for patients with good performance status, we use tagraxofusp, ALL-based chemotherapy regimens, or clinical trials as frontline induction therapy, followed by consolidation with allogeneic stem cell transplant once the first complete response has been achieved. Our induction regimen also includes intrathecal chemotherapy for central nervous system prophylaxis. Patients with poor performance status who are treatment-naïve or patients with relapsed/refractory disease have limited therapeutic options, and we strongly recommend enrollment in clinical trials; several novel agents and combinations are currently under clinical investigation for both treatment-naïve and relapsed/refractory BPDCN.

Reprogramming the tumor microenvironment by genome editing for precision cancer therapy

The tumor microenvironment (TME) is essential for immune escape by tumor cells. It plays essential roles in tumor development and metastasis. The clinical outcomes of tumors are often closely related to individual differences in the patient TME. Therefore, reprogramming TME cells and their intercellular communication is an attractive and promising strategy for cancer therapy. TME cells consist of immune and nonimmune cells. These cells need to be manipulated precisely and safely to improve cancer therapy. Furthermore, it is encouraging that this field has rapidly developed in recent years with the advent and development of gene editing technologies. In this review, we briefly introduce gene editing technologies and systematically summarize their applications in the TME for precision cancer therapy, including the reprogramming of TME cells and their intercellular communication. TME cell reprogramming can regulate cell differentiation, proliferation, and function. Moreover, reprogramming the intercellular communication of TME cells can optimize immune infiltration and the specific recognition of tumor cells by immune cells. Thus, gene editing will pave the way for further breakthroughs in precision cancer therapy.

Blastic plasmacytoid dendritic cell neoplasm with skin and bone marrow involvement: Report of three cases

BACKGROUND

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and highly aggressive hematopoietic malignancy. BPDCN is difficult to diagnose because of the overlap in morphologic and immunophenotypic features with various cutaneous lymphatic hematopoietic tumors.

CASE SUMMARY

We report on three BPDCN cases, all characterized by skin nodules and examined by histology, immunohistochemical detection, in situ hybridization for Epstein-Barr virus, and follow-up. We also review the relevant literature. All patients were positive for CD56 and negative for Epstein-Barr encoded small RNA. Two patients had bone marrow involvement. Chemotherapy is the main treatment for BPDCN, but case 1 showed bone marrow suppression and case 2 developed recurrence after chemotherapy. Case 1 survived for 7 mo, case 2 for 17 mo, and case 3 for 9 mo.

CONCLUSION

An accurate pathological diagnosis is a precondition for treatment, and the diagnosis of BPDCN should be based on a combination of clinical symptoms, pathological characteristics, immunophenotype, and other auxiliary examinations. It is necessary to clarify the clinicopathological features and biological behavior of BPDCN to improve its understanding by both clinicians and pathologists. Case 2 survived significantly longer than the other two cases, suggesting that the treatment received by case 2 was more effective.

Targeting CD123 in BPDCN: an emerging field

INTRODUCTION

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic malignancy with historically poor outcomes for patients, often refractory to traditional chemotherapy. Recent research has focused on targeted therapy to improve responses and limit potential toxicity.

AREAS COVERED

CD123 (also known as IL-3 Rα) is a cell surface marker and attractive therapeutic target for many myeloid malignancies, particularly BPDCN, whose cells ubiquitously overexpress CD123. We review the history of CD123 research regarding BPDCN, recent advances including FDA approval of tagraxofusp (formerly SL-401) for BPDCN, and ongoing clinical studies utilizing novel therapeutic strategies to target CD123.

EXPERT OPINION

The approval of tagraxofusp for the treatment of BPDCN in December 2018 drastically changed the treatment landscape for patients with this rare neoplasm. While tagraxofusp is better tolerated than traditional multi-agent chemotherapy regimens, it requires close monitoring and sound clinical judgment by providers to prevent and mitigate severe treatment-related complications with special attention to the recognition and management of capillary leak syndrome (CLS). Several other promising strategies for targeting CD123 in BPDCN are currently under investigation, including antibody-drug conjugates, T-cell engagers, and CAR-T cellular therapeutics. These CD123 targeted approaches may soon become standard of care for patients with this difficult to treat malignancy.

Venetoclax in relapsed/refractory blastic plasmacytoid dendritic cell neoplasm with central nervous system involvement: a case report and review of the literature

BACKGROUND

We describe a patient with blastic plasmacytoid dendritic cell neoplasm with central nervous system involvement and the outcome of venetoclax use in this setting.

CASE PRESENTATION

A 54-year-old Caucasian male was referred to the Haematology Unit with an enlarged inguinal lymph node which was diagnostic of a blastic plasmacytoid dendritic cell neoplasm. The staging revealed disseminated disease (skin, visceral, lymph nodes, and bone marrow). He received chemotherapy with an acute myeloid leukaemia-like regime. Afterwards, he underwent allogeneic haematopoietic stem cell transplantation, though it was not successful, showing a relapse 14 months later with hepatic and central nervous system dissemination. Intrathecal chemotherapy was administered, and venetoclax (anti-bcl2 agent) was started in an off-label indication based on most recent literature. The disease halted its course for 3 months. In the end, the patient's disease progressed and so he succumbed due to infectious complications.

CONCLUSIONS

Venetoclax monotherapy seems not enough to control the disease progression under CNS involvement and other treatments should be investigated.

Pediatric blastic plasmacytoid dendritic cell neoplasm: report of four cases and review of literature

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematological malignancy with poor outcome. Four children with BPDCN treated at our hospital were enrolled. All the four cases presented with cutaneous lesions. Bone marrow and central nervous system was involved in 50% and 25% of patients, respectively. The whole exome sequencing analysis revealed that KMT2 family genes were the most frequently mutated (4/4, 100%), followed by IKZF2 (2/4, 50%). The point mutation p.D348N was found in three patients and one patient had p.C394Y mutation in the KMT2C gene. Translocation of KMT2A-MLLT3 was found in Case 2. Case 1 had complex karyotype, who was induced by acute myeloid leukemia-like regimens. Although he received allogeneic hematopoietic stem cell transplantation twice as well as CD123 chimeric antigen receptor T cell therapy, the disease still progressed and he died 37 months after diagnosis. The other three patients were treated with Interfant-99 protocol. They tolerated the therapy well without significant toxicities and now in complete remission so far with a median follow up time of 9 months. More studies are needed to address the question whether the complex karyotype and KMT2 family genes are the causes of the relapse and refractory in BPDCN.

IL3RA-Targeting Antibody-Drug Conjugate BAY-943 with a Kinesin Spindle Protein Inhibitor Payload Shows Efficacy in Preclinical Models of Hematologic Malignancies

IL3RA (CD123) is the alpha subunit of the interleukin 3 (IL-3) receptor, which regulates the proliferation, survival, and differentiation of hematopoietic cells. IL3RA is frequently expressed in acute myeloid leukemia (AML) and classical Hodgkin lymphoma (HL), presenting an opportunity to treat AML and HL with an IL3RA-directed antibody-drug conjugate (ADC). Here, we describe BAY-943 (IL3RA-ADC), a novel IL3RA-targeting ADC consisting of a humanized anti-IL3RA antibody conjugated to a potent proprietary kinesin spindle protein inhibitor (KSPi). In vitro, IL3RA-ADC showed potent and selective antiproliferative efficacy in a panel of IL3RA-expressing AML and HL cell lines. In vivo, IL3RA-ADC improved survival and reduced tumor burden in IL3RA-positive human AML cell line-derived (MOLM-13 and MV-4-11) as well as in patient-derived xenograft (PDX) models (AM7577 and AML11655) in mice. Furthermore, IL3RA-ADC induced complete tumor remission in 12 out of 13 mice in an IL3RA-positive HL cell line-derived xenograft model (HDLM-2). IL3RA-ADC was well-tolerated and showed no signs of thrombocytopenia, neutropenia, or liver toxicity in rats, or in cynomolgus monkeys when dosed up to 20 mg/kg. Overall, the preclinical results support the further development of BAY-943 as an innovative approach for the treatment of IL3RA-positive hematologic malignancies.

Blastic plasmacytoid dendritic cell neoplasms: results of an international survey on 398 adult patients

The purpose of this study is to describe the clinical and prognostic features and to evaluate the outcome of different therapeutic approaches among patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN) who have been diagnosed and treated in different institutions. A total of 398 patients from 75 centers were included in the study. Treatment consisted of non-Hodgkin lymphoma (NHL)-like regimens in 129 (32.8%) patients and acute leukemia (AL)-like regimens in 113 (23.5%) patients. In 61 (15.5%) and 16 (4.1%) patients, chemotherapy was followed by allogeneic and autologous hematopoietic stem cell transplantation (HSCT), respectively. Twenty-seven (6.9%) patients received radiotherapy, 6 (1.5%) received new agents, and 62 (15.7%) received palliative care. After a median follow-up of 12 months, median overall survival (OS) was 18 months. Patients who received NHL/AL-like regimens, followed by allogeneic HSCT, had the best outcome; median OS was not reached. OS was 65 months for patients who underwent autologous HSCT; 18 months and 14 months, respectively, for those treated with AL-like and NHL-like regimens without consolidation; and 4 months for those receiving palliative care (P < .001). In BPDCN, chemotherapy with lymphoma- or AL-like regimens, followed by transplantation, represents the therapeutic strategy associated with the best outcome. Consolidation with allogeneic HSCT, when feasible, appears superior to autologous HSCT.

Dendritic Cell Leukemia: a Review

PURPOSE OF REVIEW

The purpose of this review was to summarize the clinical, diagnostic, and therapeutic features of blastic plasmacytoid dendritic cell neoplasm (BPDCN).

RECENT FINDINGS

Several case reports and series revealed new clinical, molecular, diagnostic, and therapeutic aspects of the disease. The clinical presentation diversity has been confirmed, with frequent leukemic non-cutaneous or rare atypical manifestations. The clonal evolution in the development of BPDCN has not been sufficiently elucidated. Although certain immunophenotypic markers (CD4, TCL1, CD123, CD56, CD303) are indicative of BPDCN, the diagnosis remains in certain cases challenging. Adult (ALL)-type chemotherapy followed by hematopoietic stem cell transplantation (HSCT) is related to a favorable outcome, while chemotherapy alone seems enough in children. Future studies should continue to investigate whether CD123-directed therapies could be utilized. BPDCN is a rare aggressive malignancy that needs an aggressive induction therapy. Although a diagnostic consensus is still lacking, and large retrospective studies are also needed to obtain standardized treatment guidelines, the future perspectives are encouraging, because of novel therapeutic agents that are under investigation.

Chemotherapy Options for Blastic Plasmacytoid Dendritic Cell Neoplasm

BPDCN is ultimately a bone marrow disease requiring induction-type eradication therapy followed by hematopoietic stem cell transplant (HSCT) to achieve long-lasting remissions or cure. Various regimens have been applied to this disease with varying success. A cumulative review of the literature suggests more intense regimens have greater efficacy with acute lymphoblastic leukemia regimens preferred to acute myeloid leukemia regimens. This approach benefits fit patients who are eligible for HSCT; however, most BPDCN patients require other treatment options. The recent FDA approval of the CD123-targeted agent tagraxofusp provides a novel therapeutic alternative to traditional chemotherapy but with potential toxicities.

Blastic Plasmacytoid Dendritic Cell Neoplasm: State of the Art and Prospects

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an extremely rare tumour, which usually affects elderly males and presents in the skin with frequent involvement of the bone-marrow, peripheral blood and lymph nodes. It has a dismal prognosis, with most patients dying within one year when treated by conventional chemotherapies. The diagnosis is challenging, since neoplastic cells can resemble lymphoblasts or small immunoblasts, and require the use of a large panel of antibodies, including those against CD4, CD56, CD123, CD303, TCL1, and TCF4. The morphologic and in part phenotypic ambiguity explains the uncertainties as to the histogenesis of the neoplasm that led to the use of various denominations. Recently, a series of molecular studies based on karyotyping, gene expression profiling, and next generation sequencing, have largely unveiled the pathobiology of the tumour and proposed the potentially beneficial use of new drugs. The latter include SL-401, anti-CD123 immunotherapies, venetoclax, BET-inhibitors, and demethylating agents. The epidemiologic, clinical, diagnostic, molecular, and therapeutic features of BPDCN are thoroughly revised in order to contribute to an up-to-date approach to this tumour that has remained an orphan disease for too long.