Microwave Radiation—Therapeutic Application for Cure of Liver Tumor

The electromagnetic fields have a great influence on the behaviour of all the living systems. Microwaves occupy range in the EM spectrum is between frequencies of 300 MHz to 300 GHz with wavelengths of approximately 1 m to 1 mm. From several decades, hyperthermia has become major subject of interest in investigating the biological effects and applications of microwaves. Therapeutic applications of microwave ablation include treatment of liver tumors, lung tumors, throat cancer, and cardiac treatments [1-4]. In this application microwave energy is used to create localised dielectric heating (diathermy) resulting in controlled destruction of tissue. This paper investigates the potential for using high-frequency microwave energy which selectively kills tumorous cells while producing minimal damage to surrounding healthy tissue. As microwaves have shorter wavelengths the choice of frequency can benefit the application, for example large volume ablations can typically be made at 915 MHz and 2.45 GHz and use of higher frequencies in the range 5.8 GHz 10 GHz can create shallow penetration of energy resulting in very precise ablations suitable for treatments such as ablation of the heart to treat arrhythmia, multiple small liver metastases [8]. Traditional microwave energy sources used in these procedures have poor efficiency, their large size requiring them to be located far from the patient. But recent studies represents that microwave heating can be used to be effective for the tumors and cardiac treatment.