64 yrs old male. Threpine biopsy was taken with suspition of lymphoma. LDH 220 (N). Generalized lymphadenopathy, febrility, hepato- splenomegaly. BLOOD WBC 4,36 (N);  RBC 4,71 (N); HB 129  ( sligthly dim); PLT 227  (N);

STEP 1: BM: MPN NOS, favor ET was detected (incidentally) and approved by JAK2 V617F+. Additionally heterogenous CD3 >> CD20+ nodular central infiltrates was detected and diagnosis of T NHL: PTCL or AILT was formulated.

STEP 2: NODE BIOPSY: Partially effaced architecture with neoplastic diffuse expanded T zone+ huge hyper=hyperplastic follicles with rimming of CD4+ cells with some follicullothropism.

FULL IH (NODE): CD3/CD5/CD7+100% ; Bcl2(+)(weak) 100%; CD8/Granzym B/CD57(-); Ki67 ~50% (+++)(brand. r-ja); focal irregular CD23/CD21+ proliferation;  EBER+ aggregates perifolicularly.

MOLECS (node): pending. BM: not enough DNA (uninformative; focal lesions).

SPECIAL QUEST: variant of T NHL in NODE.

PROPOSED DIAGNOSIS:

BM: MPN, NOS (favor ET)+ T NHL (AILT vs PTCL).

NODE: PTCL with features of AILT.

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