This is a device and method for treating eight kinds of cancer with ultraviolet radiation. The cancers include ovarian, urinary (including bladder), melanoma, uterine, adult leukemia, lymphoma (Non-Hodgkin's), lung and prostate. The main claim is that people with these cancers treated with this device and method will live longer than people not treated in this way. The device gives off ultraviolet radiation whose energy level in the ultraviolet B range is three watts per square meter. The method entails exposure to the device for twenty minutes, three times a week on non-consecutive days. The idea that exposure to ultraviolet that is intense enough might increase the lifespan of people with these cancers comes from an analysis of US state cancer death rates. The more intense the ultraviolet reaching the ground, the fewer people die.