A study examined the diagnostic and prognostic significance of various phenotypic markers. Tumor necrosis factor receptor associated factor (TRAF1), multiple myeloma oncogene 1 (MUM1), B-cell lymphoma 2 (BCL2) and CD15 were measured in patients with CD30+ lymphoproliferative disorders. These comprised lymphomatoid papulosis (LyP; n = 39), primary anaplastic large cell lymphoma (C-ALCL; n = 28), mycosis fungoides with large cell transformation (MF-TR; n = 11), anaplastic lymphoma kinase positive ALCL (ALK+ALCL; n = 2) and ALK-ALCL (n = 6). TRAF1 and MUM1 were found in 70-80% of all groups with CD30+ lymphomas. For BCL2 the rank order of frequency was MF-TR (73%)>LyP (36%)>C-ALCL (21%). For CD15, the ranking was C-ALCL (43%) ...