John Garner

PLGA-PEG-PLGA thermogel from PolySciTech used in development of highly-controlled microwave ablation technique

Blog Post created by John Garner on Jan 29, 2018

Park, 2018 polyscitech thermal ablation microwave.png

Amongst cancer treatments, ablation (the application of heat, cold, or chemicals in a minimally invasive manner directly to the tumor) has gained attention as a method to treat cancer without the systemic damage of chemotherapy or the invasive injuries from standard surgery. One of these techniques, microwave thermal ablation, works by using microwave energy to locally heat the tumor which kills the cancer while minimally affecting surrounding tissues. Recently, Researchers at Brown University/Rhode Island Hospital utilized PolyVivo (AK088) from PolySciTech (www.polyscitech.com) to develop a cesium-salt loaded thermogel which acted to increase the local heating in the vicinity of the tumor improving the effectiveness of thermal ablation. They tested these in an animal model and found the method to be highly effective with minimal side effects. This research holds promise to improve therapeutic options for tumor treatment with minimal side effects. Read more: Park, William Keun Chan, Aaron Wilhelm Palmer Maxwell, Victoria Elizabeth Frank, Michael Patrick Primmer, Jarod Brian Paul, Scott Andrew Collins, Kara Anne Lombardo et al. "The in vivo performance of a novel thermal accelerant agent used for augmentation of microwave energy delivery within biologic tissues during image-guided thermal ablation: a porcine study." International Journal of Hyperthermia 34, no. 1 (2018): 11-18. http://www.tandfonline.com/doi/abs/10.1080/02656736.2017.1317367

 

  “Abstract: Objectives: To investigate the effects of a novel caesium-based thermal accelerant (TA) agent on ablation zone volumes following in vivo microwave ablation of porcine liver and skeletal muscle, and to correlate the effects of TA with target organ perfusion. Materials and methods: This prospective study was performed following institutional animal care and use committee approval. Microwave ablation was performed in liver and resting skeletal muscle in eight Sus scrofa domesticus swine following administration of TA at concentrations of 0 mg/mL (control), 100 mg/mL and 250 mg/mL. Treated tissues were explanted and stained with triphenyltetrazolium chloride (TTC) for quantification of ablation zone volumes, which were compared between TA and control conditions. Hematoxylin and eosin (H&E) staining was also performed for histologic analysis. General mixed modelling with a log-normal distribution was used for all quantitative comparisons (p = 0.05). Results: A total of 28 ablations were performed in the liver and 18 in the skeletal muscle. The use of TA significantly increased ablation zone volumes in a dose-dependent manner in both the porcine muscle and liver (p < 0.01). Both the absolute mean ablation zone volume and percentage increase in ablation zone volume were greater in the resting skeletal muscle than in the liver. In one swine, a qualitative mitigation of heat sink effects was observed by TTC and H&E staining. Non-lethal polymorphic ventricular tachycardia was identified in one swine, treated with intravenous amiodarone. Conclusions: The use of a novel TA agent significantly increased mean ablation zone volumes following microwave ablation using a porcine model. The relationship between TA administration and ablation size was dose-dependent and inversely proportional to the degree of target organ perfusion, and a qualitative reduction in heat-sink effects was observed. Keywords: Image-guided thermal ablation, thermal accelerant, augmentation of microwave energy, complete ablation, the heat sink effect”

Outcomes