RESUMEN
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare subtype of acute leukemia that typically follows a highly aggressive clinical course in adults, whereas experience in children with this disease is very limited. We report cases of two children in whom bone marrow showed infi ltration by large atypical monocytoid ‘blast-like’ cells which on immunophenotyping expressed CD4, CD56, HLA-DR and CD33 while were negative for CD34 other T-cell, B-cell and myeloid markers. The differential diagnoses considered were AML, T/NKcell leukemia and acute undifferentiated leukemia. Additional markers CD303/ BDCA-2 and CD123 which are recently validated plasmacytoid dendritic cell markers were done which helped us clinch the diagnosis of this rare neoplasm. An accurate diagnosis of BPDCN is essential in order to provide prompt treatment. Due to its rarity and only recent recognition as a distinct clinicopathological entity, no standardized therapeutic approach has been established for BPDCN.
RESUMEN
[Objective] To quantify CD123+ BDCA-2+ plasmacywid dendritic cells (PDCs) in skin lesions and peripheral blood of patients with psoriasis vulgaris,and to investigate their significance.[Methods] Skin tissue samples were resected from the lesions of 22 patients with psoriasis vulgaris and normal skin of 15healthy controls,and peripheral blood samples were also obtained from these subjects.Immunohistochemical technique (SP) was used to quantify PDCs in skin tissue samples,and flow cytometry to determine the proportion of PDCs in peripheral blood samples.[Results] Immunohistochemical study showed that the density of PDCs in the psoriatic lesions was significantly higher than that in the healthy controls (( 10.1 ± 2.1 )/mm2 vs.(0.4 + 0.6)/mm2,t =17.34,P ＜ 0.01 ).On the contrast,the proportion of PDCs in peripheral blood was 0.17％ ±0.07％ in the patients with psoriasis vulgaris,significantly lower than that in the healthy controls (0.33％ ±0.20％,t =4.48,P ＜ 0.01 ).[Conclusion]s The proportion of PDCs is reduced in the peripheral blood of patients with psoriasis vulgaris,which may be related to the initiation and progression of psoriasis vulgaris.
RESUMEN
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.