Vascular modulation for enhancement of image-guided RF ablation since its clinical debut, image-guided radiofrequency (RF) ablation of tumors has been significantly refined, making the technique applicable to patients with primary and metastatic tumors of increasing sizes and complexities. Although considerable innovations have improved ablation technology, numerous issues have prevented this approach from surpassing other invasive means of tumor treatment. Effective follow-up and re-treatment of tumors have also been problematic because of difficulty in detecting and differentiating recurrences from inflammatory reaction. Our proposed technique uses mild vasoactive agents to improve both local image-guided ablation and post ablation imaging assessment. The inherent differences between normal and tumor vascularity can be intensified by administration of these vasoactive drugs. The resulting blood flow differences between normal and neoplastic tissue may provide differentiation between the two entities that is apparent on contrast-enhanced CT and/or CT perfusion images and may lead to improved ablation outcomes and follow-up procedures. We hypothesize that our selected vasoactive agents can modulate tumor blood flow to maximize the efficacy of tumor ablation. Furthermore, these vasoactive drugs can induce perfusion changes, which consistently predict the tumor-free margin following the ablation procedure. If successful, this combination of technologies has the potential to be translated quickly into clinical practice and improve the outcome of image-guided interventional oncology applications. The project will be carried out in three aims.
Aim 1 will be utilized to test the effect of pharmacological manipulation on the outcome of RF ablation and to optimize the treatment techniques.
Aim 2 will explore the application of vasoactive agents in distinguishing inflammation from tumor regrowth following an ablation procedure. Finally, Aim 3 will validate the results with a radiologic-pathologic correlation.
Our study evaluates a new approach for the improvement of image-guided radiofrequency (RF) ablation treatment of tumors and for optimized follow-up after the ablation treatment. This approach uses mild, clinically used vasodilators to divert blood flow from the tumors, permitting a more exact and more effective ablation treatment. In addition, a mild vasoconstrictor is then used to differentiate local tumor recurrence from normal inflammation in the ablated region in long-term imaging follow up. Both techniques address clear needs in the field of tumor RF ablation and will result in less invasive, more effective patient care. The use of available, safe vasoactive agents will allow rapid translation to clinical studies upon successful completion of the proposed research.
