Tumor-induced overexpression of Fas has been demonstrated in various types of malignancies (Ferrarini et al., 1999; Gastman et al., 1999; Kume et al., 1999; Cheng, 2006), and may be a mechanism of cancer-driven immune evasion, accounting for increased apoptosis seen in tumor infiltrating lymphocytes. The gene discussed is FAS; the disease is neoplasm.