A feasibility and dosimetric evaluation of endoscopic radiofrequency ablation for human colonic and rectal epithelium in a treat and resect trial

Abstract

Endoscopic RFA is capable of delivering therapy to the distal colon. Injury is limited to the muscularis propria or less depth when no more than two ablations are applied regardless of the energy density used. Based on these feasibility and dosimetry results, the authors will continue investigation using these and smaller energy doses to initiate trials ultimately with patients who have suitable mucosal and submucosal disorders of the lower gastrointestinal tract including chronic, nonulcerated hemorrhagic radiation proctitis and angiodyplasia.

Radiofrequency ablation for the treatment of radiation proctitis

“…Dray Xavier et al Radiofrequency ablation for radiation proctitis … Endoscopy 2014; 46: 970-976 colon and rectum [12]. The authors histologically assessed 51 focal RFA areas created in normal segments of the colon and rectum in delimited surgical resection specimens of 16 patients undergoing colectomy.…”

“…The authors histologically assessed 51 focal RFA areas created in normal segments of the colon and rectum in delimited surgical resection specimens of 16 patients undergoing colectomy. Their main conclusion was that the deepest ablative effect was limited to the muscularis propria when no more than two ablations were applied in the same location, regardless of the energy density used (12 -20 J/cm 2 ) [12]. The use of RFA in radiation proctitis was then described in 11 patients from five different series [13 -17].…”

Structural markers observed with endoscopic 3-dimensional optical coherence tomography correlating with Barrett's esophagus radiofrequency ablation treatment response (with videos)

“…There are other possible confounding variables that may contribute to depth variation or incompleteness of the ablation, including variation of the RFA electrode contact with the esophagus and coagulated/sloughing debris building up on the electrode surface with repeated ablations in a patient. 31 Indeed, we found a correlation between the BE epithelium thickness and the presence of residual glands immediately after RFA, suggesting not all RFA applications were effective. Insufficient energy delivery at the treatment sites or leaving BE unburned may be factors that lead to endoscopically visible residual BE at follow-up.…”

“…This result was not surprising, however, since the dosage of the RFA treatment has been set to achieve best efficacy with minimum injury depth. 6, 31 The energy delivery of a standard RFA application might not reach deep enough when the BE epithelium is thick. There are other possible confounding variables that may contribute to depth variation or incompleteness of the ablation, including variation of the RFA electrode contact with the esophagus and coagulated/sloughing debris building up on the electrode surface with repeated ablations in a patient.…”

Radiofrequency ablation for the treatment of radiation proctitis: a case report and review of literature

“…In order to examine the depth of the injury induced by RFA in the colon and rectum, Trunzo and colleagues performed a study on 18 patients undergoing left hemicolectomy or proctocolectomy for different indications [Trunzo et al 2011]. Focal RFA was performed in normal segments of the colon and rectum.…”