REGULAR CONTENT
Final ID
417
Type
Original Scientific Research-Oral or Pos
Authors
J Morrison1, C Schlager1, A Lee2, R van Breemen2, R Gaba1
Institutions
1University of Illinois Hospital, Chicago, IL, 2University of Illinois at Chicago, Chicago, IL
Purpose
Combined transarterial chemoembolization (TACE) and percutaneous thermal ablation has shown clinical efficacy in hepatocellular carcinoma treatment. When TACE precedes ablation, thermal effects on locally delivered chemotherapy are unknown. This bench top study assessed whether heat-based ablation results in destructive effects on TACE chemotherapy, with the hypothesis that drug survives thermal ablative heating.
Materials & Methods
Fresh porcine psoas major muscle (3 samples, 15x10x3 cm) was submerged in aqueous doxorubicin (DOX) solution (60 mcg/mL, 0.1 M) for 24 hours to passively saturate tissue. DOX-infused tissue was then dried and treated with microwave ablation (MWA), performed using a 2.45 GHz antenna (Certus 140, Neuwave Medical) at 65W for 2, 5, and 10 minutes. Ablations were repeated in triplicate (9 total). Tissue was then sampled with an 8 mm punch biopsy device (Sklar Surgical Instruments) at both ablated and unablated (control) sites, and DOX concentration in these specimens was quantified via liquid chromatography tandem mass spectrometry (LC-MS/MS), with samples analyzed in triplicate. Tissue DOX levels in ablation and control groups were compared using 1-way ANOVA.
Results
Homogeneous DOX uptake into porcine tissue was visibly evident in 100% (3/3) instances. Mean DOX concentration in unablated tissue was 8.0±2.2 mcg/mL. MWA was technically successful in 100% (9/9) instances, with tissue heating to 95-100°C. Mean tissue DOX concentration showed progressive reduction with increasing ablation time, measuring 6.7±1.3, 4.9±0.9, and 4.8±1.3 mcg/mL in MWA treated tissue after 2, 5, and 10 minutes. Differences in tissue DOX levels between unablated tissue and MWA groups were statistically significant (P<0.001).
Conclusions
Study results opposed the initial hypothesis, showing that tissue DOX concentration decreases after MWA, with incremental reduction in DOX with increasingly longer MWA duration. However, DOX remains present within ablated tissues, albeit in lesser quantity. Although limited by ex vivo design, this study suggests that a clinical locoregional therapy strategy of TACE followed by ablation may result in lower intra-tumoral DOX than would otherwise be anticipated for TACE alone.
Final ID
417
Type
Original Scientific Research-Oral or Pos
Authors
J Morrison1, C Schlager1, A Lee2, R van Breemen2, R Gaba1
Institutions
1University of Illinois Hospital, Chicago, IL, 2University of Illinois at Chicago, Chicago, IL
Purpose
Combined transarterial chemoembolization (TACE) and percutaneous thermal ablation has shown clinical efficacy in hepatocellular carcinoma treatment. When TACE precedes ablation, thermal effects on locally delivered chemotherapy are unknown. This bench top study assessed whether heat-based ablation results in destructive effects on TACE chemotherapy, with the hypothesis that drug survives thermal ablative heating.
Materials & Methods
Fresh porcine psoas major muscle (3 samples, 15x10x3 cm) was submerged in aqueous doxorubicin (DOX) solution (60 mcg/mL, 0.1 M) for 24 hours to passively saturate tissue. DOX-infused tissue was then dried and treated with microwave ablation (MWA), performed using a 2.45 GHz antenna (Certus 140, Neuwave Medical) at 65W for 2, 5, and 10 minutes. Ablations were repeated in triplicate (9 total). Tissue was then sampled with an 8 mm punch biopsy device (Sklar Surgical Instruments) at both ablated and unablated (control) sites, and DOX concentration in these specimens was quantified via liquid chromatography tandem mass spectrometry (LC-MS/MS), with samples analyzed in triplicate. Tissue DOX levels in ablation and control groups were compared using 1-way ANOVA.
Results
Homogeneous DOX uptake into porcine tissue was visibly evident in 100% (3/3) instances. Mean DOX concentration in unablated tissue was 8.0±2.2 mcg/mL. MWA was technically successful in 100% (9/9) instances, with tissue heating to 95-100°C. Mean tissue DOX concentration showed progressive reduction with increasing ablation time, measuring 6.7±1.3, 4.9±0.9, and 4.8±1.3 mcg/mL in MWA treated tissue after 2, 5, and 10 minutes. Differences in tissue DOX levels between unablated tissue and MWA groups were statistically significant (P<0.001).
Conclusions
Study results opposed the initial hypothesis, showing that tissue DOX concentration decreases after MWA, with incremental reduction in DOX with increasingly longer MWA duration. However, DOX remains present within ablated tissues, albeit in lesser quantity. Although limited by ex vivo design, this study suggests that a clinical locoregional therapy strategy of TACE followed by ablation may result in lower intra-tumoral DOX than would otherwise be anticipated for TACE alone.