PATIENT: 70-year-old male  
CLINICAL HISTORY: persistent fatigue, weight loss, febrile fever, heavy sweating for 5 months.  
CLINICAL EXAMINATION: Hepatopslenomegaly, lymphadenopathy.  
PET-CT scan: diffuse and focal FDG uptake in bone marrow, lymph nodes (left axillary, suprarenal and paraaortic), foci in liver and spleen.  
LAB WORKUP: Pancytopenia, LDH 535 (U/L) (N <250 (U/L)).  
HISTO:  
Trephine biopsy: diffuse and focal infiltrate, composed of:  
•Small lymphocytes CD2/CD3/CD5, CD4+, CD8(-), PD1+ >ICOS+.  
•Vaguely clustered B population of small/medium-sized and giant cells CD20/CD79a+, Bcl6+ > Pax5+, BOB1/OCT2+, CD10/CD30/CD15/EMA/MUM1(-); EBER(-).  
•CD68+ macrophages.  
•Absent FDC (CD23/CD21-).  
Lymph node:  
•Small monotonous CD5/CD2/CD7+, CD4+, CD8(-), PD1+ > ICOS+ lymphocyte infiltrate between abundant hyaline deposits.  
•Small foci of extranodal extension.  
•Absent giant cells, sparse/focal CD20/PAX5+ lymphocytes.  
•Absent FDC (CD23/CD21-).  
Clonal IGH profile, non-clonal IGK/IGL/TCR profile in BM infiltrate.  
Non-clonal IG and TCR profile in lymph node infiltrate.  
 
PROPOSED DDIAGNOSIS:  
NHL “T lymphocyte rich with large B cells”. Probable diagnosis: AITL > vs NLP HL?  

tzankov 2020-10-01 18:20	I see your point, Ugnius.   The clinical presentation is clearly in favor of AITL.   Finally, the histopathology too: the rather significant amount of eosinophils, the lack of clear-cut L&H cells and the tightly arranged PD1+ cells as well as the very high CD4 : CD8 ratio, all better fit with AITL than with NLPHL. If you are still in doubt - then run clonality testing.
ugnius 2020-10-02 16:00	Thanx. Interestingly theay got B clone from fresh threpine material.