Microwave Ablation (MWA) for Solid Tumors

Microwave Ablation (MWA) is a minimally invasive procedure used to destroy solid tumors in patients who cannot undergo traditional surgery due to age, comorbidities, or tumor location. Rather than cutting out the tumor, MWA used high-frequency electromagnetic energy to heat and kill cancer cells from within. It is most commonly applied to tumors of the liver, lung, and kidney and operates at frequencies of either 915 MHz or 2.45 GHz. As researchers have noted, MWA has emerged as a treatment that "effectively induces tumor necrosis through localized heating" while causing minimal disruption to surrounding healthy tissue (Xu et al).

During the procedure, one or more thin antenna probes are inserted directly into the tumor, guided by imaging such as ultrasound, CT, or MRI. The antennas are connected to a microwave generator, and the energy they emit causes water molecules in the tumor tissue to rapidly rotate and generate intense heat. Tissue ablation occurs quickly within one minute after a pulse of energy, and multiple pulses may be delivered within a single treatment session depending on tumor size. In tumors greater than 2 cm in diameter, “two to three antennas may be used simultaneously to increase the targeted area and shorten operative time” (South Carolina Blues Medical Policy). 

Recovery from MWA is generally faster and less demanding than recovery from open surgery. Because the procedure is most often performed on an outpatient basis, many patients go home the same day. Common post procedure side effects include mild pain, fever, and discomfort at the insertion site, all of which typically resolve within days. The cells destroyed by MWA are not surgically removed; instead, they are gradually replaced by scar tissue over time. Possible complications, though less common, include heat damage to nearby tissue, liver enzyme changes, or fluid buildup, depending on which organ was treated. Follow up imaging is used to monitor the treated area and confirm that no recurrence has occurred at the margins. 

Written by Malak Ibrahim at Incisionary

References

Jiang, Y., & et al. (2019). Microwave ablation (MWA): Compared to radiofrequency ablation, larger tumors can be treated [Image]. ResearchGate. https://www.researchgate.net/figure/Microwave-ablation-MWA-Compared-to-radiofrequency-ablation-larger-tumors-can-be_fig5_338026987

Xu, Y., et al. (2025). Advancements in microwave ablation for tumor treatment and future directions. PMC/National Library of Medicine. https://pmc.ncbi.nlm.nih.gov/articles/PMC12017980/

South Carolina Blues. (n.d.). Microwave tumor ablation. South Carolina Blues Medical Policy. https://www.southcarolinablues.com/web/public/brands/medicalpolicy/external-policies/microwave-tumor-ablation/