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Microwave ablation (MWA) uses electromagnetic methods to induce the destruction of tumors via thermal energy at frequencies ≥ 900 MHz [33]. A generator emits an electromagnetic wave through an antenna resulting in the application of heat to tissues. It has several advantages over radiofrequency ablation, including consistently higher intratumoral temperatures leading to larger ablation zones and shorter treatment times; it has an active heating mechanism that allows for more uniform tumor necrosis even in close proximity to large blood vessels; it can be effective in tissues with high impedance such as lung or charred, desiccated tissue; and multiple tumors can be treated simultaneously with an additional antenna [34, 35].

The most common generators include Emprint^TM (Medtronic, Boulder, CO) and Neuwave^TM (NeuWave Medical, Madison, WI). The Medtronic antennas come in three different shaft lengths, 15, 20, and 30 cm, but the radiating (green) section of the probe that becomes hot with use is 2.8 cm on all probes. The NeuWave probes vary in size from 13to17 gauge and lengths of 15, 20, and 25 cm. Power and time settings are recommended by the manufacturer depending on the tissue type, size of the lesion, and number of probes used.

In people, MWA has been described via an open approach, percutaneously via image guidance and with laparoscopy and thoracoscopy. There is limited published information on MWA in veterinary medicine and even more limited information on its use with laparoscopy and thoracoscopy. Yang et al. [36] described the use of MWA with an open approach for the treatment of hepatic neoplasia in five dogs. More recently, Oramas et al. [37] described the feasibility of laparoscopic access to the liver lobes in cadaveric dogs and then detailed the use of MWA with laparoscopy in two clinical cases of hepatic neoplasia. Video‐assisted MWA of pulmonary metastasis has also been reported in a dog [38].