This is a 31/ M with a diagnosis of mediastinal gray zone lymphoma treated with DA-EPOCHR x 6 with persistent disease with a plan to do brentuximab vedotin and nivolumab. Images are from a relapse tissue showing variable CD20 (strong at diagnosis) in the persistent disease likely related to rituximab therapy.

The strong CD45 and strong expression of CD79a and PAX5 supports designation as persistent gray zone lymphoma despite the variable CD20 which is otherwise consistent with a cHL immunophenotype.