Microwave Ablation: A Powerful but Underused Modality for Treatment of Spine Tumors

Dr. Khan completed his radiology residency in New York and his fellowship in neuroradiology at John Hopkins. As he progressed in the field, he observed a significant shift in spinal care towards interventional methods and began to study these techniques, which included radiofrequency ablation (RFA) and cryoablation for treating spinal tumors. However, when he treated cases of prostate cancer spine metastases, he realized that RFA was challenging, due to the high bone impedance of osteoblastic lesions. This obstacle piqued his interest in microwave ablation, an alternative technique that employs an electromagnetic wave to induce rapid oscillation of hydrogen atoms in water molecules. This oscillation generates frictional heat, leading to coagulative tumor necrosis. Unlike RFA, microwave ablation significantly reduces bone impedance, making it a promising solution for these cases.

Dr. Khan cautions that special care must be taken when operating in areas near nerves due to the elevated temperatures. To ensure safety, he recommends the use of a probe within the frequency range of 900 MHz to 1.2 GHz and the incorporation of thermocouplers as a safeguard during the ablation process. Furthermore, Dr. Khan delves into the indications for ablation based on the extent of tumor metastasis. In cases of oligometastatic disease, he advises a more aggressive treatment approach by extending the ablation zone beyond the actual tumor size. On the other hand, when dealing with diffusely metastatic disease, the primary goal of treatment shifts towards pain reduction.

The two conclude their discussion with Dr. Khan’s advice for physicians planning to utilize microwave ablation. He advises them to approach their initial 5-10 cases judiciously, in an effort to minimize the risk of complications that may adversely impact their self-confidence. Having adequate self confidence enhances the likelihood of achieving successful outcomes. For those looking for a valuable resource in the field, Dr. Khan has recently published a comprehensive textbook that features contributions from experts in the field.