CONVENTIONAL PHOTOS PENDING.  
history: 73 yrs old male with cervical lymphadenopathy. 3 biopsies were taken: LN1 from the neck (2009 Feb), threpine biopsy (2009 May, staging) and LN2 from supraclavicular LN.  
HISTO: 2 cell populations: 1) DLBCL (immunoblastic) with Ki67 ~40%; 2) lymphoplasmacytic/"paraimunoblastic" low grade with Ki67 ~5%. FDC networks are absent (CD21/CD23). The "maconudolarity" without FDC is present in some extent.  
IH: Bcl6+; Mum1+; Ig kappa+; IgM+; CD10(-); Bcl2+; CD43+; CD5/CD23/CD30(-); CD79a+ > CD20+ (CLL or "marginal/plasmoid" like pattern).  
BM: Unsatisfactory for full IH panel, CD20+ lymphoid infiltration about 10% NOS (not included in photos).  
VIRTUAL SLIDES: APPERIO.  
JPG: snapshots from virtual slides.  
DIAGNOSIS: Diffuse large B cell lymphoma, probably evolving from B low grade lymphoma (MzL with aberrant Bcl6+ vs FL)?  
 
SPECIAL QUEST: The interpretation of B low grade component.  
 
Thank you for beeing 2gether for a long long time.

tzankov 2009-10-20 14:49	I agree with your interpretation of at least focal DLBCL transformation of a "secretory" low grade B-cell lymphoma (MZL vs. lymphoplasmacytic immunocytoma IgM/kappa). Did the patient have a history of rheologic complications? Retinopathy for example?
hurwitz 2009-10-20 18:46	Yes, I agree with your interpretation of focal transformation (immunoblastic ) of a low grade lymphoma, probably MZL. By the way Bcl6 expression has been reported in MZL.
hurwitz 2009-10-28 15:45	THe diagnosis of the submitter can be confirmed:   DLBCL evoloving from low grade lymphoma, probably marginal zone lymphoma (aberrant bcl6 expression)