A rare type of primary cutaneous diffuse large B-cell lymphoma that does not belong in the group of primary cutaneous diffuse large B-cell lymphomas, leg type, or the group of primary cutaneous follicle center lymphomas. It includes subtypes/entities of diffuse large B-cell lymphoma (e.g. intravascular large B-cell lymphoma, plasmablastic lymphoma, T-cell/histiocyte rich lymphoma) that can involve the skin as the primary anatomic site. Such cases, unlike their nodal counterparts, usually have an excellent prognosis. [from
NCI]