TNF and cancer: Studies involving regional (Lienard et al, 1992; Mavligit et al, 1992; Lejeune et al, 1998) or intratumoral (van der Schelling et al, 1992) injection of TNFα have demonstrated its potential for cancer therapy, but only when a high enough therapeutic concentration of TNFα was obtained in the tumour with a nontoxic systemic concentration.