The American Cancer Society estimates that 965 000 new cases of invasive cancer will be diagnosed in 1987. Of that number, 71% of the patients will present with local and/or regional extension. Only 56% of those will be cured by standard treatment techniques.1 A considerable proportion of patients who die will do so because of failure to control the disease process locally and regionally. This is clearly evident in patients who have malignant tumors of the head and neck, gastrointestinal tract, gynecologic system, genitourinary system, and skin, bone, and soft tissue.
To improve the potential for local control, multiple therapies have been investigated. These include brachytherapy with radiation and/or surgery, surgery and radiation therapy, intra-raterial chemotherapy and radiation therapy, high linear energy transfer radiation, and, most recently, hyperthermia.
The rationale for hyperthermia in cancer therapy is based on various biologic effects that have been confirmed in many in vitro