Transformation of Mixed Cellularity Classical Hodgkin Lymphoma to Diffuse Large B-cell Lymphoma: A Case Report and Literature Review

The development of diffuse large B-cell lymphoma (DLBCL) in patients with a history of classical Hodgkin lymphoma (cHL) is a well-established but rarely documented event, particularly when it originates from the mixed cellularity subtype, an occurrence that has been minimally reported and documented.We present the case of a 47-year-old woman with mixed cellularity classical Hodgkin lymphoma (MC-cHL), Lugano stage IV, who underwent hematopoietic cell transplantation, subsequently relapsed, and later developed DLBCL, raising the possibility of histologic transformation.She was treated with polatuzumab vedotin, rituximab, and ibrutinib.