A groundbreaking study has demonstrated that cryoablation (CA) is more effective and safer than microwave ablation (MWA) for treating paravertebral metastatic tumors in rabbits. Researchers achieved an impressive 86.67% complete ablation rate with cryoablation compared to just 63.33% with microwave ablation, amidst rising concerns over the treatment options for severe metastatic pain.
As the incidence of malignant tumors rises globally, many advanced cases exhibit metastases situated in difficult anatomical locations. Paravertebral metastases can lead to debilitating pain and neurological deficits, severely impacting patients' quality of life. Both cryoablation and microwave ablation are increasingly utilized to target tumors in various organs. However, comparative data on their effectiveness specifically for paravertebral metastatic tumors remains sparse. This study aims to fill this gap by systematically evaluating the two ablation methods in a controlled environment.
In conducting this study, a rabbit VX2 paravertebral metastasis model was established, demonstrating a successful modeling rate of 88.23% (60 of 68 rabbits). The rabbits were randomly divided into two groups: one underwent microwave ablation while the other received cryoablation. The complete ablation rate found in the CA group highlighted its superior effectiveness, providing a promising avenue for further clinical exploration.
Significantly, the operation time recorded for cryoablation was longer, averaging 42.6 minutes versus 28.2 minutes for microwave ablation, indicating that while CA may require more time, it delivers better outcomes. Pain assessment scores, evaluated via the Bristol Rabbit Pain Scale, also showed a noteworthy reduction in the CA group compared to MWA, underscoring cryoablation’s potential for providing effective pain relief.
Follow-ups conducted after 21 days revealed an alarming complication rate of 33.33% for the MWA group against only 10% in the CA group, suggesting a marked safety advantage for cryoablation. The MWA group experienced several severe complications, including cases of skin injury and lower-limb sensory impairment, emphasizing the need for careful consideration of treatment approaches.
This study utilized a comprehensive methodological approach, involving CT-guided modeling and sophisticated ablation techniques. Both CA and MWA procedures were performed under the guidance of experienced professionals to ensure accuracy. The CA procedure utilized a double-cycle freezing method, which allowed for controlled monitoring of the ablation zone, thereby minimizing the risk of damage to surrounding nerve structures.
Detailed imaging assessments using MR scans confirmed that cryoablation maintained reliable delineation of treatment areas, a notable advantage over microwave ablation where the ablation margins can often be ambiguous. Postoperative assessments indicated that rabbits undergoing cryoablation experienced significantly lower pain scores at multiple time points after treatment, validating its efficacy in pain relief.
However, the researchers acknowledged the limitations of their work, including a relatively short follow-up period that restricts the comprehensive understanding of long-term outcomes. They called for larger studies with extended follow-ups to explore the clinical implications of their findings further.
With this study's revelation that cryoablation is associated with higher efficacy and fewer complications than microwave ablation, the researchers hope to influence future clinical protocols addressing paravertebral metastatic tumors. This investigation lays the groundwork for maximizing patient safety and optimizing treatment effectiveness in the face of increasingly complex cancer cases.
