The effects of radiofrequency ablation on the hepatic parenchyma: Histological bases for tumor recurrences

Radiofrequency Ablation: Inflammatory Changes in the Periablative Zone Can Induce Global Organ Effects, including Liver Regeneration

“…The proliferation pattern observed with the CDC47 marker temporally overlapped the BrdU positivity (ablated lobe: P , .05 at 8 hours, P , .001 starting from the 72-hour time point; untreated lobe: P , .001 starting from the 72-hour time point) ( Fig E6 [online], Fig 4). Peak proliferation was noted at 7 days, albeit with a significant zone is stained with Sirius Red from the 72-hour time point, becoming ever progressively prominent until the 14-day time point (Fig E4 [on-line]), correlating with the accumulation of the activated myofibroblasts and consistent with previous findings (16,24). Furthermore, in this area, senescence-associated b-galactosidasel staining (which is a marker for senescence [21]) showed that cells at the border zone begin to senesce from the 72-hour time point, with the process largely accelerating several days after the fibrosis to reach a peak 14 days after ablation (Fig E5 [online]).…”

“…The temporal distribution was selected on the basis of previous studies that noted that the kinetics of tissue response is greatest between 72 hours and 21 days after RF ablation (15,16). In addition, neutrophils accumulate in response to tissue damage 7 hours to 3 days after ablation; thus, the 24-hour time point was also selected (17).…”

Radiofrequency Ablation Versus Resection for Liver Tumours: An Evidence-Based Approach to Retrospective Comparative Studies

“…[13][14][15][16] One centimetre is usually considered the minimum safe macroscopic margin for tumour ablation and a 5-cm ablation is required for the safe destruction of a tumour (including the transitional zone) with a diameter of approximately 3 cm. 10,17 These encouraging results have prompted some authors to advocated the use of a multicentre randomized controlled trial to compare RFA and HR in patients with resectable tumours; 12,18 but to date, this has not yet been performed. Our intention is to review critically the literature that directly compares the two treatment options, analyse the results with an evidence-based approach in order to determine whether a future large randomised study is justified.…”

Gross and microscopic changes of liver neoplasms and background hepatic structures following neoadjuvant therapy

“…Typically, the tumour will show necrotic changes including pale discolouration and a softer texture than the background. In the later stages of healing, the necrotic focus may harden and become surrounded by a thickened and fibrotic capsular-like area leading to the treated zone being slightly smaller than the size of the lesion prior to treatment 73. If present, residual tumour is most likely to be found at the periphery of the treated zone (figure 2A).…”

“…A fibrous pseudocapsule is often present and may be seen overlying a congested area with extravasated red blood cells. RFA-treated lesions may show a microscopic haemorrhagic rim surrounding the necrotic core 73. When no residual tumour is present, scar tissue may be seen in addition to congested vessels and areas with hemosiderin-laden macrophages (figure 2D).…”