Scientific (exp)/research
Changes in interleukin-1β and 6 after hepatic microwave tissue ablation compared with radiofrequency, cryotherapy and surgical resections

https://doi.org/10.1016/j.amjsurg.2009.12.025Get rights and content

Abstract

Background

Cytokine changes after microwave tissue ablation (MTA) were compared with hepatic resection, cryotherapy (CRYO), and radiofrequency ablation (RFA). Cytokine production was measured at various ablation volumes for each modality and correlated with the transitional inflammatory zone produced by the ablation techniques.

Methods

Live rats underwent MTA, surgical resection, CRYO or RFA of 15%, 33%, or 66% of the total hepatic volume. Serum samples were collected preoperatively and at 1, 3, 6, 24, and 48 hours after surgery and analyzed for pro-inflammatory cytokines interleukin (IL)-1β and IL-6.

Results

Significantly higher levels of both cytokines were present after CRYO and RFA compared with MTA, hepatic resection, or controls (P < .001). All animals survived except those undergoing RFA or CRYO of 66% of the hepatic volume, which died within 6 hours. Transitional zones produced after RFA were larger than those after CRYO or MTA, but no correlation was present with the amount of cytokines.

Conclusions

Large-volume MTA is associated with a significant decreased cytokine response and is well tolerated compared with RFA and CRYO.

Section snippets

Materials and Methods

Ethical approval was sought in accordance with the Animals Act 1986 (Scientific Procedures). Adult male Sprague–Dawley rats (350–400 g; Charles River Laboratories, Margate, UK) were allowed to acclimatize in the designated establishment for 1 week and underwent the same diet and handling.

Results

All animals in the 66% ablation volume group that received CRYO or RFA ablation died within 24 hours. No animal died in any of the laparotomy, resection, and MTA groups.

Histological Correlation

All histology samples obtained after thermal ablations showed a uniform central zone of coagulative necrosis surrounded by a peripheral rim of inflammation (Fig. 2). Transitional zones obtained after RFA were significant larger compared with MTA and to CRYO (ANOVA test; P < .05), while no differences were present between MTA and CRYO (ANOVA test; P = NS) (Figure 2, Figure 3). No significant correlation existed between the transitional zone thickness and the AUC or the mean maximal values of

Comments

To investigate the effects of ablative treatments several clinical and animal studies have attempted to determine the maximum volume of hepatic parenchyma that could be safely ablated without causing significant morbidity or mortality.12, 17 Some investigators have indicated that large tumor sizes and ablated volumes are associated with increased morbidity following RFA treatments2, 18 and ablation of less than 33% of the total volume was considered tolerable. The increased morbidity and

Acknowledgment

Dr David Lloyd had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

References (23)

  • J.K. Seifert et al.

    Large volume hepatic freezing: association with significant release of the cytokines interleukin- and tumor necrosis factor a in a rat model

    World J Surg

    (2002)
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