Mixed-Cellularity Classical Hodgkin Lymphoma

The second most common Hodgkin lymphoma variant (20–25%), which is characterized by a heterogeneous population of inflammatory cells (T cells, eosinophils, histiocytes, and plasma cells) that are admixed with Hodgkin cells.  Fibrosis is not evident, and EBV infection is present in approximately 70-75% of cases.  The immunophenotype is the same as other classical Hodgkin lymphoma cases.  This is the default category when a case cannot be categorized as another subtype.
 
There may be some interstitial fibrosis, but there are no nodules or broad fibrosis and the capsule is not usually thickened. 
Classical Hodgkin Lymphoma – General Information
 
Characteristic Immunohistochemical Features

References
Hematopathology. [edited by] Jaffe, ES. 1st. ed. Elsevier, Inc. © 2011.
 
Robbins and Cotran Pathologic Basis of Disease.  V Kumar, et al. 9th Edition. Elsevier Saunders. 2015.
 
WHO Classification of Tumors of Haematopoietic and Lymphoid Tissues.  SH Swerdlow, et al. International Agency for Research on Cancer. Lyon, 2008.