Blastic plasmacytoid dendritic cell neoplasm presenting as a renal mass

Cytologic features of blastic plasmacytoid dendritic cell neoplasm involving liver: A case report and literature review

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare but clinically aggressive hematologic malignancy, believed to originate from plasmacytoid dendritic cells (PDCs) although it possesses multilineage potentials. Due to the dismal prognosis, accurate and rapid diagnosis is critical for early management. The disease usually initially involves skin and bone marrow. Here we report the cytopathologic findings in a case of BPDCN involving the liver in a patient previously diagnosed with BPDCN from skin and lymph node biopsies. The fine-needle aspiration specimen from the liver lesion demonstrates a hypercellular smear of atypical epithelioid cells dispersed singly or in loose groups. These cells have enlarged, eccentric, round to irregular nuclei with fine chromatin. The agranular gray-blue cytoplasm shows delicate wispy cytoplasmic extensions and cytoplasmic microvacuoles. Binucleation is common. The concurrent core biopsy shows that the neoplastic plasmacytoid cells with eccentric nuclei were positive for CD4, CD7, CD43, CD56, and CD68, confirming the diagnosis of BPDCN. Mutations of ASXL1 and TET2, classic for BPDCN, and a complex karyotype were detected in skin, bone marrow, and lymph node specimens. We catalog the heterogeneous pathologic features of this rare disease, emphasizing the clinical and histopathological correlation. The differential diagnoses and review of literature are also included. Awareness of this disease and accurate diagnosis are emphasized to aid early management and potentially produce a better clinical outcome.

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.

Pediatric Blastic Plasmacytoid Dendritic Cell Neoplasm: A Systematic Literature Review

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare aggressive hematologic malignancy characterized by frequent skin involvement that most commonly affects older patients. BPDCN is known to have a poor prognosis. Our objective was to assess if outcome and disease prognosis were independently influenced by age when evaluated with clinical presentation, sex, and treatment regimens. We conducted a systematic review to identify BPDCN cases, to compare pediatric BPDCN cases with adult cases. A total of 125 publications were identified detailing 356 cases. Including 1 pediatric case from our institution, 74 were children, and 283 were adults aged 19 or over. Age was shown to be an independent prognostic factor predictive of more favorable outcomes across measures including initial response to therapy, likelihood of relapse, and overall survival at follow-up. The distribution of affected organs at diagnosis was similar across children and adults and type of clinical presentation did not disproportionately influence 1 age group's prognosis over the other. Acute lymphoblastic leukemia-type chemotherapy regimens were shown to be superior to other chemotherapy regimens (acute myeloid leukemia, lymphoma, acute lymphoblastic leukemia/lymphoma, other, or none) in inducing complete remission. Allogeneic stem cell transplantation was shown to increase mean survival time. Future research may be directed toward elucidating the further morphologic, cytogenetic, and cytochemical differences between younger and older BPDCN patients.

Blastic plasmacytoid dendritic cell neoplasm: a report of four cases and review of the literature

BACKGROUND

Blastic plasmacytoid dendritic cell neoplasm (BPDCN), formerly known as agranular CD4(+) /CD56(+) haematodermic neoplasm (CD4/CD56 HN), is a rare distinct form of lymphoma-like entity known of dermatologists because of its marked predilection for cutaneous involvement, and its aggressive behaviour. Moreover, the association or the evolution to an acute leukaemia entity that still expresses CD4 and CD56 markers is almost systematic. This new described entity of 'CD4(+) /CD56(+) leukaemia' or 'leukaemia of plasmacytoid dendritic cell lineage' has a poor prognostic and may lead to include haematopoietic stem cell transplantation in the treatment strategy as early as possible.

REPORT OF CASES

We report here four cases presenting with skin lesions and haematological signs. One of the patients underwent allogeneic stem cell transplantation, with a relapse-free survival of 40 months. We discuss the diagnosis features as well as the treatment options.

CONCLUSION

A collaborative work between dermatologists and onco-haematologists is essential to give patients the best chance of complete and long-term response.