Therapeutic hyperthermia in cancer and AIDS: an updated survey

The aim of this paper is to update with personal contributions the progress thus far accomplished in the clinical application of hyperthermia (HT) in cancer and chronic infectious diseases. The HT treatment has been successfully developed since the 1970s in cancer patients in whom it showed positive results consisting of complete or partial clinical remissions. Its rationale was based on the fact that core temperatures of > or = 42 degrees C induce cytotoxic effects that are higher in malignant cells than in normal cells. HT could be applied by different methods according to type, stage, and localization of the malignancies. Thus, systemic whole-body HT (WBH), through invasive or noninvasive techniques, was first used in disseminated cancers; local perfusion, infusion, and interstitial HTs have been applied in limb, skin, subcutaneous, or intracavitary tumors. The observation of a macrophagic lysosomal exocytosis and subsequent cancer cell death induced by HT, suggested that its mechanism of action involves an immune reaction. This suggested the possibility of associating HT with cytotoxic agents, antibiotics, antiviral drugs, and antioxidants, including beta-carotene (BC). The association of HT with BC at high doses are synergistic in patients with AIDS-related complex (ARC) and improve its symptoms, preventing the progress of the disease into the severe stage of AIDS; the same synergism helped also to increase the survival time in patients with severe AIDS.