Immunohistochemistry can sub-classify diffuse large B-cell lymphoma (DLBCL) into germinal centre B-cell like (GCB) and non-GCB subtypes. The latter consists predominately of the activated B-cell like subgroup in which nuclear factor kappa-B activation is its characteristic. Expression of cellular caspase 8 (FLICE)-like inhibitory protein (cFLIP), a caspase 8 homologue, is regulated by nuclear factor kappa-B signalling, and it is the main inhibitor of Fas ligand activated apoptosis. To determine if cFLIP expression was confined to non-GCB subtype, we studied 66 cases of DLBCL. cFLIP expression showed no significant correlation to DLBCL subtypes (GCB or non-GCB) but was associated with a worse clinical outcome. For cFLIP positive and negative patients, the five-year event free survival was 20 and 31%, respectively (p= 0.049), and the five-year overall survival was 20 and 57%, respectively (p= 0.041).