Immunoprevention of cancer: Is the time ripe?

Immunotherapy applied to patients with established tumors rarely leads to a n objective response, whereas patients apparently free from disease after c onventional treatment and at risk of recurrence are beginning to receive va ccination. New classes of patients or not-yet patients are those with a hig h genetic or environmental risk of developing cancer. They may draw benefit from a "soft" treatment such as vaccination. This overview discusses the p rospects of immune stimulation as a means of cancer prevention by inducing various forms of nonspecific or even specific immunity. Attainment of this goal provides the rationale and motivation for embarking on such a new and potentially rewarding enterprise.