CORRInsights®: Is Limb Salvage With Microwave-induced Hyperthermia Better Than Amputation for Osteosarcoma of the Distal Tibia?
Hyperthermia has long been used to ablate tumors. But unlike radiofrequency ablation, which requires a conductive field for heating, microwaves can heat tissues by transmitting kinetic energy to polar molecules like water. Microwaves can transfer heat through charred tissue. Tissues, like bones and lungs, are better treated with microwaves than radiofrequency ablation [12, 17] because microwaves, by using multiple antennae, can heat larger tumor volumes faster and at higher temperatures than radiofrequency ablation. Therefore, microwaves are the ideal way to generate heat for larger volumes of tumors in bone tissues.
The development of needle-like, internally-cooled antennae allows for more energy to dissipate with more uniform heating. Placing multiple antennae in specific configurations can rapidly achieve the temperatures required for tumor ablation. Monitoring the temperature within the tumor, and in vital areas like joint cartilage or neuromuscular bundles, help limit potential damage.
Building off of the results from previous studies [5, 6], Han and colleagues use an unconventional approach for limb salvage in distal tibial tumors. In order to avoid a complete bony osteotomy at the proximal site, the authors used microwave-generated hyperthermia to ablate the tumor after dissecting and isolated the tumor with margin from the surrounding tissues.