UPGRADED:  
 
OF NOTE: the case close to published and discussed before (attached)(T LBL+ interdigitating cell tumor): https://www.ipath-network.com/inctr/object/view/26258  
 
69 yrs male with cervical lymphadenopathy (from April; up to 6cm) and whole LN biopsy.  
STORY: Weaknes, 10 kg loss. Herpetic eruption on the neck skin (2015 March). No hepatosplenomegaly, edemas or B symptoms.  
BLOOD: 18.57 LEU; Blasts ~80%.  
 
BM FLOW: Blast population 81%: CD45+ dim, CD34+, CD38+ strong, CD99+, TdT+, HLA-DR+ dim, CD1a+ partial, CD2+ heterogenous, cCD3+, CD5+, CD7+ strong, CD13+ dim, CD33+ dim, sCD3-, CD4-, CD8-, CD10-, CD19-, cCD79a-, CD117-, cMPO-.  
GENESIS- T lymphoid: A-LBL (pre T ?). Aberrant expression of myeloid Ags (CD13, CD33).  
 
MOLECS: pending.  
Threpine: The same infiltration of T LBL with small lympho- histiocytic nodule with S100+Lysozyme+ and CD123 cell admixture.  
 
HISTO: Binary: "dark" LBL (T) infiltration with intermingled "clear" histyoid areas of S100+ only cells. Some DC2 cell nodules around (CD123+ strong).  
IH: "DARK" LBL (T): CD3+/- faint; CD7+; CD5+; TdT+; MPO(-); CD34/CD117+ weak; Ki67 high.  
"CLEAR" HISTYOID CELLS: S100+; Bcl2+ weak; TdT(-); CD1a/Langerin(-);  
DC2 nodules: CD123+ strong; TdT(-)?.  
 
PROPOSAL: COMPOSITE BLASTOID TUMOR:  
NODE: 1) T LBL+ 2) Interdigitating dendritic cell tumor (vs dendritic undetermined?)+ 3) plasmacytoid dendritic cell proliferation, probably reactive.  
BM: The same T LBL infiltration with small nidus of interdigitating cell tumor with concommitant DC2 cell infiltration (reactive).  
 
COMMENT:  
1. A case quite similar to discussed before (link and paper attached there), including reactive DC2 (plasmacytoid dendritic) cell nodules (in previous case- within BM).  
2. Some scattered MPO+ immature cells within TdT+ dark blast population? Some (same?) myeloid component on FLOW.  
 
Thanx for all done.

tzankov 2015-07-24 14:09

super case, I agree with you that we probably have a pre-(early) T-LBL/ALL with "indeterminate dendritic NPL" like in the previos case. the plasmacytoid nodules coule be a "monoblastoid" outgrowth of the tumor like in those cases associated with CMML/AMML. the mpox+ cells are for me reactive.