79yrs old woman with aspiration biopsy from breast module. CYTOLOGICAL diagnosis: adenocarcinoma. Sectoral resection and lymphonodectomy were performed.  
HISTO: highly atypical intrasinusoid cells clusters.  
IH: CD20+; CD30+ (faint); CD15+ (sic!!!); Bcl6/CD10(-); Mum1+; Bcl2+; CD21+; ALK1(-), CD3/CD5(-), Ki67 ~95%; CD23; CD43(-), EBV LMP1/EBV EBER(-), Bcl6(-), GranzymB(-), CD138(-), CD10(-), Ig kappa/lambda without definite restriction.  
 
PROPOSED DIAGNOSIS: Intrasinusoidal CD30+ CD15+ (microvillous) DLBCL (ABC, anaplastic variant).  
Differential: cHL with predominant intrasinusoid spread.  
 
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