2.5 GHz microwave thermal ablation for performing thermosensitive polymer-chemotherapy for cancer

Microwave Ablation (MWA) is a promising technology for treating hepatic tumors. Combined macromolecular thermo-targeted chemotherapy and MWA are expected to provide better tumor control than either method independently. The MWA will heat and destroy the tumor core. It will also produces a hyperthermic zone for further destruction at the tumor margin by focal, locoregional accumulation of thermo-sensitive biosynthetic and bio-organic polymergelanamycin (GA) conjugate to kill surviving cancer cells. This will produce a significant reduction in tumor recurrence and increased cancer eradication as evaluated by survival endpoints. The minimum temperature requirement at the tumor periphery for the polymer-GA to destroy the tumor cell is 43°. Microwave coaxial-cable interstitial antennas have been developed in the past for hyperthermia. Current technology limits a single ablated region to approximately 3 cm. Several types of coaxial-based antennas, including the coaxial slot antenna, coaxial dipole antenna, coaxial monopole antenna, coaxial cap-choke antennas, and others have been designed for MWA or microwave hyperthermia therapies in an attempt to prevent this backward heating while creating as large an ablation radius as possible. The cap-choke antenna seems to most efficiently prevent backward heating. This paper describes the design of a microwave ablation device that can provide the required temperature distribution on the surface of the tumor. It also uses beamforming for multi-antenna ablation to more uniform and controlled heating.