Blastic Plasmacytoid Dendritic Cell Neoplasm in Children

Nail as a Window to Diagnosing Multisystem Langerhans Cell Histiocytosis: A Case Report and Review of Literature

ABSTRACT

Nail involvement in Langerhans cell histiocytosis is rarely reported in the literature. According to the reported cases, it is believed that the involvement of nails has a poor prognosis because of multisystem involvement. Performing a nail bed biopsy might be challenging for children. We report a child in whom nail bed biopsy served as the sole clue to the diagnosis of Langerhans cell histiocytosis in absentia of skin clue on a background of advanced multisystem involvement.

Blastic plasmacytoid dendritic cell neoplasm in Jinhua, China: Two case reports

BACKGROUND

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and clinically aggressive hematologic malignancy originating from the precursors of plasmacytoid dendritic cells. BPDCN often involves the skin, lymph nodes, and bone marrow, with rapid clinical progression and a poor prognosis. The BPDCN diagnosis is mainly based on the immunophenotype.

CASE SUMMARY

In this paper, we retrospectively analyzed 2 cases of BPDCN. Both patients were elderly males. The lesions manifested as skin masses. Morphological manifestations included diffuse and dense tumor cell infiltration of the dermis and subcutaneous tissues. Immunohistochemistry staining showed that cluster of differentiation CD4, CD56, CD43, and CD123 were positive.

CONCLUSION

In this paper, we retrospectively analyzed 2 cases of BPDCN. Both patients were elderly males. The lesions manifested as skin masses. Morphological manifestations included diffuse and dense tumor cell infiltration of the dermis and subcutaneous tissues. Immunohistochemistry staining showed that cluster of differentiation CD4, CD56, CD43, and CD123 were positive.

Blastic plasmacytoid dendritic cell neoplasm: a comprehensive review in pediatrics, adolescents, and young adults (AYA) and an update of novel therapies

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy that can involve the bone marrow, peripheral blood, skin, lymph nodes, and the central nervous system. Though more common in older adults, BPDCN has been reported across all age groups, including infants and children. The incidence of pediatric BPDCN is extremely low and little is known about the disease. Pediatric BPDCN is believed to be clinically less aggressive but often with more dissemination at presentation than adult cases. Unlike adults who almost always proceed to a hematopoietic stem cell transplantation in first complete remission if transplant-eligible, the majority of children can be cured with a high-risk acute lymphoblastic leukemia-like regimen. Hematopoietic stem cell transplantation is recommended for children with high-risk disease, the definition of which continues to evolve, or those in relapse and refractory settings where outcomes continue to be dismal. Novel agents used in other hematologic malignancies and CD123 targeted agents, including chimeric antigen receptor T-cells and monoclonal/bispecific antibodies, are being brought into research and practice. Our goal is to provide a comprehensive review of presentation, diagnosis, and treatment by review of pediatric cases reported for the last 20 years, and a review of novel targeted therapies and therapies under investigation for adult and pediatric patients.

Top Ten Lymphoproliferative Lesions Not to Miss When Evaluating Oral Ulcer Biopsies

BACKGROUND

Oral ulcers represent a full thickness loss of the mucosal epithelium leading to exposure of the submucosal connective tissue. These are common and usually self-limited lesions, although they may sometimes result from neoplasms, most commonly squamous cell carcinoma. Lymphoproliferative disorders may be difficult to diagnose in apthous ulcers since they mimic reactive inflammation.

METHODS

This review presents ten rare oral lymphoid proliferations which should not be missed when assessing oral ulcer biopsies.

RESULTS

The ten lesions include several with diagnostic cells which look similar to the histiocytes of a reactive inflammatory ulcer, including Rosai-Dorfman disease, reticulohistiocytoma, Langerhans cell histiocytosis, and traumatic ulcerative granuloma. Other lesions, such as EBV-positive mucocutaneous ulcer, extranodal marginal zone lymphoma of mucosal-associated lymphoid tissue, and plasmablastic lymphoma have lymphoid and/or plasma cell differentiation that mimic the reactive lymphocytes and plasma cells found in reactive ulcers. Two dendritic cell lesions, follicular dendritic cell sarcoma and blastic plasmacytoid dendritic cell neoplasm, both have distinct phenotypes which are required to make an accurate diagnosis.

CONCLUSION

Each of these lesions are diagnosed by evaluating their histology, along with their phenotypic profile, which is sometimes enhanced by pertinent molecular findings.

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.

North American Blastic Plasmacytoid Dendritic Cell Neoplasm Consortium: position on standards of care and areas of need

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy with historically poor outcomes and no worldwide consensus treatment approach. Unique among most hematologic malignancies for its frequent cutaneous involvement, BPDCN can also invade other extramedullary compartments, including the central nervous system. Generally affecting older adults, many patients are unfit to receive intensive chemotherapy, and although hematopoietic stem cell transplantation is preferred for younger, fit individuals, not all are eligible. One recent therapeutic breakthrough is that all BPDCNs express CD123 (IL3Rα) and that this accessible surface marker can be pharmacologically targeted. The first-in-class agent for BPDCN, tagraxofusp, which targets CD123, was approved in December 2018 in the United States for patients with BPDCN aged ≥2 years. Despite favorable response rates in the frontline setting, many patients still relapse in the setting of monotherapy, and outcomes in patients with relapsed/refractory BPDCN remain dismal. Therefore, novel approaches targeting both CD123 and other targets are actively being investigated. To begin to formally address the state of the field, we formed a new collaborative initiative, the North American BPDCN Consortium (NABC). This group of experts, which includes a multidisciplinary panel of hematologists/oncologists, hematopoietic stem cell transplant physicians, pathologists, dermatologists, and pediatric oncologists, was tasked with defining the current standard of care in the field and identifying the most important research questions and future directions in BPDCN. The position findings of the NABC's inaugural meetings are presented herein.

Pediatric Blastic Plasmacytoid Dendritic Cell Neoplasm, Clinical Features and Immunophenotype: A Case Report

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare but aggressive malignancy with high mortality involving the skin and hematopoietic system. Clinical suspicion is difficult, and management of skin lesions is challenging due to their indolent course prior to dissemination. We describe a patient with isolated skin involvement who progressed to CD4+/CD56+ and CD123+ acute leukemia.

Allogeneic hematopoietic stem cell transplantation with myeloablative conditioning regimen for blastic plasmacytoid dendritic cell neoplasm patients in complete remission: a single center study

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematopoietic malignancy characterized by poor prognosis even following an allogeneic hematopoietic stem cell transplantation (allo-HSCT). We retrospectively analyzed 15 patients diagnosed with BPDCN who underwent an allo-HSCT with myeloablative conditioning (MAC) at our center. The male to female ratio was 11:4. The median age of 36 (range: 6-70) years, all patients initially presented with extramedullary lesions (13 with cutaneous lesions, 1 in the breast and 1 in the lymph nodes) and involved the bone marrow, two cases were diagnosed as central nervous system leukemia (CNSL). Nine patients were in CR1 and six patients were in CR2 status prior to HSCT. All patients received the MAC regimen and an unmanipulated graft. All patients successfully engraftment and achieved full donor chimerism. One patient developed poor graft function, three patients developed aGVHD (Grade I, II, and IV), and seven patients developed cGVHD (mild in 6; moderate in 1). The median follow-up time for survival was 34 (range: 6-64) months. The primary endpoint, overall leukemia-free survival (LFS) rate and overall survival rate was 73.3 ± 10.5%. Allo-HSCT with MAC is a valid option for BPDCN patients in complete remission.

A Rare Case of Blastic Plasmacytoid Dendritic Cell Neoplasm in a Child Mimicking Lymphoma/Leukemia Cutis

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare tumor that affects elderly individuals and presents a poor prognosis. Skin is the most common site of involvement, accounting for 89% of the cases. Extracutaneous organs, especially bone marrow, lymph nodes, and peripheral blood, can be involved at the time of diagnosis. We report a case of BPDCN in a child, presenting with a cutaneous lesion mimicking lymphoma or leukemia cutis. The histologic findings revealed a dense diffuse infiltration by monomorphic agranular medium-sized blast cells with sparing of the grenz zone, whose first immunophenotypic profile raised the possibility of diagnosing B lymphoblastic lymphoma or leukemia. However, the absence of CD10 expression and strongly positive expression for CD4, CD56, CD45RA, and the plasmacytoid dendritic cell-associated antigens, including CD123, supported the definite diagnosis of BPDCN. The patient responded well to a systemic combination chemotherapy regimen, modified from the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) protocol for anaplastic large cell lymphoma (ALCL), that differed from the established recommendation using ALL protocol. Owing to the patient’s excellent treatment outcome, this regimen could represent an effective alternative regimen for BPDCN in children.

Conventional Therapeutics in BPDCN Patients-Do They Still Have a Place in the Era of Targeted Therapies?

No benchmark treatment exists for blastic plasmacytoid dendritic cell neoplasm (BPDCN). Since the malignancy is chemo-sensitive, chemotherapy followed by hematopoietic stem cell transplantation remains an effective treatment. However, relapses frequently occur with the development of resistance. New options arising with the development of therapies targeting signaling pathways and epigenetic dysregulation have shown promising results. In this review, we focus on conventional therapies used to treat BPDCN and the novel therapeutic approaches that guide us toward the future management of BPDCN.

The association of complex genetic background with the prognosis of acute leukemia with ambiguous lineage

Acute leukemia with ambiguous lineage (ALAL) is a rare and highly aggressive malignancy with limited molecular characterization and therapeutic recommendations. In this study, we retrospectively analyzed 1635 acute leukemia cases in our center from January 2012 to June 2018. The diagnose of ALAL was based on either EGIL or 2016 WHO criteria, a total of 39 patients were included. Four patients diagnosed as acute undifferentiated leukemia (AUL) by both classification systems. Among the patients underwent high-throughput sequencing, 89.5% were detected at least one mutation and the median number of gene mutation was 3 (0–8) per sample. The most frequently mutated genes were NRAS (4, 21%), CEBPA (4, 21%), JAK3 (3, 16%), RUNX1 (3, 16%). The mutations detected in mixed-phenotype acute leukemia (MPAL) enriched in genes related to genomic stability and transcriptional regulation; while AUL cases frequently mutated in genes involved in signaling pathway. The survival analysis strongly suggested that mutation burden may play important roles to predict the clinical outcomes of ALAL. In addition, the patients excluded by WHO criteria had even worse clinical outcome than those included. The association of the genetic complexity of blast cells with the clinical outcomes and rationality of the diagnostic criteria of WHO system need to be evaluated by more large-scale prospective clinical studies.