STEP 1: 63 yrs old woman was operated due to "ACUTE ABDOMEN" symptoms. The hepatosplenomegaly and lymphadenopathy were found. PB: Hb 117, LEU: 4, PLT: 167. LN biopsy was taken.  
HISTO: Difusse small lympho's proliferation (CD3+ >> CD20+) with scattered "paraimunoblasts" with the prominent eo nucleoli, CD23+ focci of medium sized cells in the sinus and cortical projection and reticulin fibrosis in medium sized cell populated areas. Some destructed CD21+ FC's are present by IH. Partially open sinuses with granulocytes and eo's. It's difficult detect and visualize larger CD23+ cells in CD5 amd CD43 cells due to heavy background.  
WORKING FORMULATION: (IMPRESSION OF LOW GRADE LYMPHOMA ARCHITECTURALLY) "atypical diffuse lymphadenopathy: clonality studies are required". Suspitious immunophenotype: CD20+ CD3- CD5/CD43?  
STEP 2: IgH monoclonality was found and threpine biopsy was taken. BM: Infiltration of small B lymphos (diffuse interstitial) 70%.IH: CD20+ CD5+ CD23+ CD43-. II° reticulin fibrosis is present.  
BLOOD: WBC (10*9/l) 4.700; LYM (%) 38.2; HgB (g/l) 123.1  
 
DIAGNOSIS: CLL/SLL with BM and minimal LN involvement (with prominent T cell reaction).  
 
Special quests: 1. Armentarium in detection of small neoplastic cell populations, obscured by reactive major population. 2. Demonstration of architecture or immunophenotype (Photography of several stains), when digital co-localisation of changes is impossible due to cutting and changing contours of the tissue.  
 
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