A Case of Blastic Plasmacytoid Dendritic Cell Neoplasm in Child / 대한피부과학회지

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and highly aggressive hematopoietic malignancy which is derived from the precursors of plasmacytoid dendritic cells and is more infrequent in children than in adults. Formerly known as blastic NK-cell lymphoma or CD4+/CD56+ hematodermic neoplasm, the BPDCN is reclassified into the group of acute myeloid leukemia and related neoplasm by WHO in 2008. An 8-year old girl is being presented with bruise-like subcutaneous nodules with purpura on her right cheek from the performed biopsy. Histological examinations show sheet-like dense infiltrations of medium-sized lymphoid cells with irregular nuclei in the entire dermis. Immunohistochemical stainings of tumor cells were positive for CD4, CD56, LCA, TCL-1, TdT and focal positive for CD3, CD7, CD45RO and negative for CD20, CD30, CD34, EBV. The PET-CT scans indicate hot uptakes in the bone marrows which are suggestive of malignant infiltrations, and bone marrow biopsy findings are consistent with BPDCN of leukemic transformations. We present a rare case of BPDCN which affects the pediatric patient.

CD 4+/CD56+ Hematodermic Neoplasm in Infancy: Case Report / 대한피부과학회지

CD4+/CD56+ hematodermic neoplasm is a rare and aggressive lesion that affects many organs, and skin involvement is highly characteristic. It is also termed blastic natural killer cell lymphoma in the World Health Organization classification. Several origins of tumor cells have been proposed, but recent studies have shown a relationship with plasmacytoid dendritic cells. A 2-year-old boy presented with multiple bruise-like violaceous subcutaneous nodules and plaques on the trunk, upper and lower extremities. Histological examination showed small-to-medium-sized blastoid cellular infiltration in the dermis and subcutaneous tissue. Tumor cells were positive for CD4, CD56 and TdT, and negative for CD8, CD20 and MPO. It primarily affects elderly patients, but, in this case, occurred in an infant. Due to its rarity, we present a case of CD4+/CD56+ hematodermic neoplasm affecting a pediatric patient.

Neoplasia hematodérmica CD4+ CD56+ en la infancia / Hematodermic CD4+ CD56+ neoplasm in childhood

La neoplasia hematodérmica CD4+ CD56+ con fenotipo de célula dendrítica plasmocitoide es una rara y agresiva neoplasia recientemente reconocida por la WHO-EORTC classification. Afecta adultos de edad media y ancianos, siendo muy pocos los casos descriptos en niños. Presentamos el caso de una niña de 12 años con grave retraso mental, estigmas genéticos y múltiples lesiones cutáneas localizadas en miembros inferiores y superiores. Histológicamente se observó un infiltrado dérmico difuso de células pequeñas y medianas con expresión de CD4, CD56, CD43 y S100 así como de marcadores dendríticos plasmocitoides: CD 123 y BDCA-2 confirmados por citometría de flujo, sin compromiso de sangre periférica ni médula ósea. Cumpliendo dos semanas de tratamiento para leucemia linfoblástica aguda evolucionó con remisión clínica de las lesiones cutaneas.

Hematodermic CD4+ CD56+ neoplasm with plasmacytoid dendritic cell phenotype is a rare and aggressive neoplasm recently recognized by the WHO-EORTC classification. It generally appears in elderly adults, exceptionally in childhood. We present a 12-year-old girl with severe mental retardation, genetic clinical features and multiple nodular cutaneous lesions on legs and arms. Histologically the nodules showed diffuse dermal infiltrate of medium and small cells and expression of CD4, CD56, CD43, S100 and plasmacytoid dendritic markers: CD123, BDCA-2 under flow cytometry study. Peripheral blood and bone marrow were not involved. Clinical remission of cutaneous lesions was observed after two weeks of acute lymphoblastic leukemia therapy.

A Case of Blastic NK-cell Lymphoma / 대한피부과학회지

A CD56+ lymphoma is a rare disease and has an aggressive behavior. Blastic NK-cell lymphoma has more aggressive characteristics and poorer prognosis than the other CD56+ lymphomas. Recently-revised WHO classification has included it as a new subcategory of primary cutaneous lymphoma. Herein we report a case of blastic NK-cell lymphoma occurred in 14 year-old Korean boy. We could differentiate it from other CD56+ lymphomas by clinical, pathological, and especially immunohistochemical findings: i.e. blastic NK-cell lymphoma is CD56+, CD3-, TdT+, EBER-. This case warrants further interest because of clear difference from Western reports in that it occurred at younger age.

Genotype of Epstein-Barr Virus and Comparative Genomic Hybridization Analysis of NK/T Cell Lymphoma

NK/T cell lymphoma is a distinct clinicopathologic entity which is more prevalent in Asia than in America and Europe and is highly associated with Epstein-Barr virus (EBV) infection. Although the clinicopathologic features of the tumor have been clearly defined, genetic changes and roles of virus associated with the development and progression of tumor have not been well studied. In this study, we carried out polymerase chain reaction (PCR) for EBNA-3B, EBNA-3C, and LMP-1 30 bp deletion to investigate EBV subtype and variants in tumor tissue and performed comparative genomic hybridization (CGH) to screen chromosomal imbalances using frozen tissues from 7 patients with nasal-type NK/T cell lymphoma and 1 patient with blastic NK cell lymphoma. Of 6 cases infected with EBV, there were EBV type 1 in six, LMP-1 30 bp deletion variant in four, and LMP-1 40 bp deletion variant in one. Frequent chromosomal imbalances included deletions at 1p31-pter (4), 12q23-q24 (3), and 17p (4), and gains at 2q (5), 10q (3), and 13q34-qter (4). Blastic NK cell lymphoma displayed deletions of 9q, 7q, and 6q, similar to that of nasal-type NK/T-cell lymphoma. With these results, we assumed that candidate genes in these imbalanced chromosomal loci would provide the clue for further molecular studies to identify putative tumor suppressor genes or proto-oncogenes associated with pathogenesis of this neoplasm.