Ch14.18/CHO represents a new kind of cancer therapy that, unlike chemotherapy and radiation, targets the destruction of cancer cells without destroying nearby healthy cells. There is laboratory evidence to suggest that ch14.18/CHO can activate the body's own immune cells to destroy cancer cells. These immune cells include killer cells that are activated or stimulated by aldesleukin (IL-2). Therefore this treatment is a combination of ch14.18/CHO and aldesleukin (IL-2).