Blastic plasmacytoid dendritic cell neoplasm: clinical features in 90 patients

T-lymphoblastic lymphoma with cutaneous involvement

To study dermatological manifestation of T-lymphoblastic lymphoma and to help clinicians in the diagnosis, we report here the case of a 75-year-old patient who presented with violaceous nodules acquired during the last 4 wk and affecting the scalp and right arm. The diagnosis of systemic lymphoma was suggested upon the appearance of cutaneous tumors, palpable lymph nodes and general symptoms including asthenia and weight-loss. The pathology features: positive immunostaining for CD3 and terminal deoxynucleotidyl transferase (TdT) and staging, led us to the final diagnosis of T-lymphoblastic lymphoma (T-LBL) with cutaneous involvement. He received a CHOP regimen as first-line treatment. Unfortunately, the patient relapsed and died 8 mo after the treatment initiation. T-LBL may be diagnosed by skin lesions. Additional immunostaining including TdT and experienced histopathologists are needed to correctly classify this aggressive disease and discuss the correct management including bone-marrow transplantation where appropriate.

Transplantation in rare lymphoproliferative and histiocytic disorders

BACKGROUND

Some uncommon lymphoproliferative and histiocytic disorders may present with an aggressive course and require hematopoietic stem cell transplantation (HSCT) as part of the therapeutic approach.

METHODS

Published research on the use of HSCT for the treatment of these disorders was reviewed and summarized.

RESULTS

Allogeneic HSCT may be indicated in patients with blastic plasmacytoid dendritic cell neoplasia, familial or secondary recurrent hemophagocytic lymphohistiocytosis, and resistant Langerhans cell histiocytosis. Autologous HSCT may be considered in patients with Castleman disease resistant to treatment. No role has been established for the use of HSCT for dendritic cell sarcoma.

CONCLUSIONS

HSCT has an evolving role in the treatment of select aggressive lymphoproliferative and histiocytic disorders.

Paediatric cutaneous lymphomas: a review and comparison with adult counterparts

Primary cutaneous lymphomas (CL) in children is rare. Only a few studies focused specifically on paediatric CL and therefore little is known whether primary CL in children are similar to or different from their adult counterparts with respect to the clinicopathological presentation, behaviour and prognosis. An extensive literature search using PubMed/MEDLINE from January 1995 through July 2014 was undertaken for articles reporting cases of paediatric CL. In addition, we identified 31 children with CL in our institutions. Mycosis fungoides and lymphomatoid papulosis are the two most prevalent lymphoma forms in children. A few entities of cutaneous lymphomas such as cutaneous diffuse large B-cell lymphoma leg type, and Sézary syndrome have not been reported so far in children. Other lymphoma entities such as hydroa vacciniforme-like lymphoma are mostly seen in certain geographic areas (Asia, Central and South America). In the paediatric population, low-malignant indolent forms such as primary cutaneous marginal zone lymphoma and primary cutaneous follicle centre lymphoma are very rare, whereas the more aggressive forms of B-cell lymphomas, precursor lymphoblastic lymphomas, and blastic plasmacytoid dendritic cell neoplasm are the most common forms in children, mostly involving the skin secondarily. Most paediatric lymphomas have similar clinicopathological features and course as their adults counterparts, particularly in the group of cutaneous T-cell lymphomas. The spectrum of cutaneous B-cell lymphomas in children significantly differs from the one in adults. Diagnostic work-up and treatment of paediatric patients with lymphomas are best achieved in close collaboration with paediatric haematopathologists and oncologists.

In vivo and in vitro sensitivity of blastic plasmacytoid dendritic cell neoplasm to SL-401, an interleukin-3 receptor targeted biologic agent

Blastic plasmacytoid dendritic cell neoplasm is an aggressive malignancy derived from plasmacytoid dendritic cells. There is currently no accepted standard of care for treating this neoplasm, and therapeutic strategies have never been prospectively evaluated. Since blastic plasmacytoid dendritic cell neoplasm cells express high levels of interleukin-3 receptor α chain (IL3-Rα or CD123), antitumor effects of the interleukin-3 receptor-targeted drug SL-401 against blastic plasmacytoid dendritic cell neoplasm were evaluated in vitro and in vivo. The cytotoxicity of SL-401 was assessed in patient-derived blastic plasmacytoid dendritic cell neoplasm cell lines (CAL-1 and GEN2.2) and in primary blastic plasmacytoid dendritic cell neoplasm cells isolated from 12 patients using flow cytometry and an in vitro cytotoxicity assay. The cytotoxic effects of SL-401 were compared to those of several relevant cytotoxic agents. SL-401 exhibited a robust cytotoxicity against blastic plasmacytoid dendritic cell neoplasm cells in a dose-dependent manner. Additionally, the cytotoxic effects of SL-401 were observed at substantially lower concentrations than those achieved in clinical trials to date. Survival of mice inoculated with a blastic plasmacytoid dendritic cell neoplasm cell line and treated with a single cycle of SL-401 was significantly longer than that of untreated controls (median survival, 58 versus 17 days, P<0.001). These findings indicate that blastic plasmacytoid dendritic cell neoplasm cells are highly sensitive to SL-401, and support further evaluation of SL-401 in patients suffering from blastic plasmacytoid dendritic cell neoplasm.

Blastic plasmacytoid dendritic cell neoplasm: skin and bone marrow infiltration of three cases and the review of the literature

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a distinct and rare neoplastic entity and was classified as a subgroup of acute myeloblastic leukemia by the WHO in 2008. The median survival of patients was 15.2 months in a large case series. Allogeneic or autologous bone marrow transplantation has been recommended by some reports because of the disease's poor prognosis. We present three patients who presented with both skin and bone marrow infiltration. A 57-year-old man, a 62-year-old woman, a 64-year-old man were admitted to our outpatient clinic because of skin lesions. All of the patient's had bone marrow infiltration with positivity of the CD4, CD56, and CD123 staining. Survival of the patient's were 42, 6 and 12 months, respectively. Two of the patients who presented as blastic form didn't respond to any chemotherapy. BPDCN is a difficult disease to diagnosis and manage. CD4, CD56, CD123, CD303, and T cell leukemia/lymphoma 1. Cutaneous lesions can present as isolated nodules, macules, and disseminated macules and nodules. Positivities are crucial to the diagnosis of the disease in histological examination. Bone marrow infiltration or disease relapse at presentation were related to poor prognosis. Complete immunocytochemical staining must be performed for all patients who have cutaneous lesions with or without blood count abnormalities. Bone marrow (allogeneic or autologous) transplantation should be considered at the first remission.

Activity of SL-401, a targeted therapy directed to interleukin-3 receptor, in blastic plasmacytoid dendritic cell neoplasm patients

This is the first prospective study of treatment of patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN), an aggressive hematologic malignancy derived from plasmacytoid dendritic cells that typically involves the skin and rapidly progresses to a leukemia phase. Despite being initially responsive to intensive combination chemotherapy, most patients relapse and succumb to their disease. Because BPDCN blasts overexpress the interleukin-3 receptor (IL3R), the activity of SL-401, diptheria toxin (DT)388IL3 composed of the catalytic and translocation domains of DT fused to IL3, was evaluated in BPDCN patients in a phase 1-2 study. Eleven patients were treated with a single course of SL-401 at 12.5 μg/kg intravenously over 15 minutes daily for up to 5 doses; 3 patients who had initial responses to SL-401 received a second course in relapse. The most common adverse events including fever, chills, hypotension, edema, hypoalbuminemia, thrombocytopenia, and transaminasemia were transient. Seven of 9 evaluable (78%) BPDCN patients had major responses including 5 complete responses and 2 partial responses after a single course of SL-401. The median duration of responses was 5 months (range, 1-20+ months). Further studies of SL-401 in BPDCN including those involving multiple sequential courses, alternate schedules, and combinations with other therapeutics are warranted. This trial is registered at clinicaltrials.gov as #NCT00397579.

Blastic Plasmacytoid Dendritic Cell Neoplasm: How do You Distinguish It from Acute Myeloid Leukemia?

BPDCN is a recently elucidated clinicopathologic entity. This disease typically involves the skin, with 30% to 40% of patients showing an additional concurrent leukemic component. Although BPDCN often exhibits cytologic features akin to acute lymphoblastic leukemia, the main differential diagnostic challenge, in the skin and in the bone marrow, is distinction from AML, in particular AML with monocytic differentiation.

CLTC-ALK fusion as a primary event in congenital blastic plasmacytoid dendritic cell neoplasm

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a subtype of acute myeloid leukemia, affecting mainly the elderly. It is thought to be derived from plasmacytoid dendritic cell precursors, which frequently present as cutaneous lesions. We have made a detailed analysis of an infant with BPDCN, who manifested with hemophagocytic lymphohistiocytosis. The peripheral blood leukocytes revealed the t(2;17;8)(p23;q23;p23) translocation and a CLTC-ALK fusion gene, which have never been reported in BPDCN or in any myeloid malignancies thus far. Neonatal blood spots on the patient's Guthrie card were analyzed for the presence of the CLTC-ALK fusion gene, identifying the in utero origin of the leukemic cell. Although the leukemic cells were positive for CD4, CD56, CD123, and CD303, indicating a plasmacytoid dendritic cell phenotype, detailed analysis of the lineage distribution of CLTC-ALK revealed that part of monocytes, neutrophils, and T cells possessed the fusion gene and were involved in the leukemic clone. These results indicated that leukemic cells with CLTC-ALK originated in a multipotent hematopoietic progenitor in utero. This is the first report of the CLTC-ALK fusion gene being associated with a myeloid malignancy, which may give us an important clue to the origin of this rare neoplasm.