TNF and neoplasm: Several in vitro clonogenic assays suggest that an additive or a supra-additive interaction may occur between TNFα and ionising radiation (Hallahan et al, 1990; Gridley et al, 1994a; Azria et al, 2003a) as well as an enhancement of the antitumour effect of radiation in some murine and human tumours in vivo (Sersa et al, 1988; Nishiguchi et al, 1990; Gridley et al, 1997; Azria et al, 2003a).