features permitting the distinction from non-hodgkin 's lymphoma included persistent reactive foci with the classic features of infectious mononucleosis , a polymorphous background of transformed lymphocytes rather than irregular or twisted lymphoid cells as seen in non-hodgkin 's lymphoma , and preservation of underlying reticulin architecture rather than destruction , even in cases with extensive immunoblastic proliferation .
C0021345
mononucleosis
C0024264
lymphocytes