Patients undergo outpatient leukapheresis on day -4 or -5, and cells are incubated ex vivo with interleukin-2 (IL-2). Lymphokine-activated killer (LAK) cells and IL-2 are infused on day 1. Bolus infusions of low-dose IL-2 are administered on days 3, 5, 8, 10, and 12, followed by a rest period on days 13-24. The course is repeated on day 25 starting with leukapheresis. Therapy courses are repeated for up to 1 year for stable disease or response to therapy. Maintenance doses repeat every 4-6 months thereafter.