82 yrs old Lady with resected breast tumor. Clin. diagnosis: "adenocarcinoma vs lymphocytoma cutis".  
MACRO: 3,5x2,5x1,5 cm skin/subcutaneous tissue with yelowish nodule 3,1x2,5 cm with 0,1 cm distance from lateral resection margin.  
HISTO: On the slides.  
IH: CD21/CD23(-)(FDC network absent); CD20(+++)(40% population; large tumor cells 100%), CD3/CD43(+++)(60% population; reactive T cells); CD10(-)(except stroma); Bcl2(++)(40% tumor population); Ki67 in tumor cells 80%; Bcl6(+/++)60% in tumor cells; Mum1 (++) 70% in tumor cells; CD138(-)(plasma cells absent); CyclinD1(-); IgM (++) 90% >> IgD(++)10% in tumor cells; Ig kappa slightly > Ig lambda (unsatisfactory?).  
IMMUNOPHENOTYPE ACTIVATED/MIXED: Bcl6+ CD10- Bcl2+ IgM+, Mum1+. Ki67 80%.  
PROPOSED DIAGNOSIS: DLBCL of the skin vs Follicular cell lymphoma (grade II) of the skin.  
QUESTION: Bcl2+ and IgM+ value in decission making in this case?  
 
PLEASE FIND a link to another breast skin B lymhoma case from our archives below.  
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