Although modern treatments for breast cancer are quite effective, some patients have chest wall recurrences – 3 to 22 percent of cases. The treatment of these recurrences is problematic, since surgery is often not practical and chemotherapy is not very effective. Since the area is likely to have been irradiated before, large doses of radiation may be impossible. One alternative is to use hyperthermia in conjunction with lower dose radiation. Hyperthermia itself can be directly cytotoxic since heated tumors are more sensitive to injury due to inadequate blood supply and low levels of oxygen and nutrients.A lower dose of radiation may be effective when hyperthermia is used. A number of studies have investigated this approach; many of them are now a decade or more in the past. National Comprehensive Cancer Network Breast Cancer Clinical Practice Guidelines in Oncology(p.89) include a consideration for hyperthermia (HT) and radiation for women with recurrent locoregional advanced breast cancers after first-line surgery or radiation failed.