Hyperthermia therapy is exploited in the medicine field combined with the most known cancer treatments - radiotherapy and chemotherapy - to improve their effectiveness. During hyperthermia treatments, the tumor tissues are heated up to 42/43°C through non-ionizing microwave radiation generated by proper antenna applicators. Overheating makes the cells more sensitive to ionizing radiations and enhances drug delivery without adding further toxicity. These benefits have been demonstrated for tumor sites like cervix, breast, head and neck, skin, bladder, and esophagus. For the treatment of internal tumors, properly phased antenna arrays are currently used in the clinical practice to maximize the specific absorption rate (SAR) (and hence the temperature increase) in the tumor target, while avoiding formation of hotspots in the surrounding healthy tissues.