Contents I. Introduction
Cancer a major public health challenge worldwide and the largest cause of death in Japan since 1981 accounting for 27.4% (373.547 deaths) of all deaths in 2018 [1]. There are different types of cancer treatment such as surgery, chemotherapy, and radiation therapy. Recently, magnetic hyperthermia has been gaining great interest as a promising cancer therapy with less invasive than surgical therapy and fewer side effects compared with chemotherapy [2]–[4]. Cancer cells are more sensitive to heat than healthy cells, and the antitumor effect occurs when the tumor is heated within the therapeutic temperature range of 40–45 °C. Magnetic hyperthermia utilizes heat generation ascribed to magnetic particles subjected to a high-frequency magnetic field [5], [6]. In addition to magnetic particles [7]–[10], important elements include techniques for detecting the position [11]–[14] and temperature [15]–[18] of magnetic particles in a tumor region in determining the effectiveness of therapeutic heating.
