Endoluminal radiofrequency ablation of the main pancreatic duct is a secure and effective method to produce pancreatic atrophy and to achieve stump closure

Abstract

Radiofrequency energy has been used both experimentally and clinically to manage the pancreatic remnant after distal pancreatectomies. Our goal was to determine whether endoluminal radiofrequency (RF) ablation of the main pancreatic duct in large animals would be more efficient than glue occlusion as an exocrine pancreatic atrophy-inducing procedure. Thirty-four Landrace pigs were assigned to either the transpapilar (n = 16) or transection (n = 18) groups. The transection implied the pancreas neck was severed. In each of these groups the remaining distal pancreatic duct was occluded either by RF or by glue. In the transpapilar group complete atrophy was observed in all the RF cases, while atrophy was incomplete in all the members of the glue subgroup. The failure rate of the main pancreatic duct (usually expressed by a pseudocyst) in the transection groups was dramatically higher in the glue subgroup than the RF subgroups (9 out of 9 and 1 out of 9, respectively) and postoperative mortality occurred only in the glue subgroup (3 out of 9). These results show the superiority of endoluminal RF ablation over glue for main pancreatic duct occlusion, as seen by the degree of atrophy and fewer postoperative pancreatic fistulas.

Pancreatic duct ligation reduces premalignant pancreatic lesions in a Kras model of pancreatic adenocarcinoma in mice

“…Therefore, the transformation to PanIN lesions of these acinar cells or their precursors could be interrupted when an early obstruction of the main pancreatic duct is performed even when Kras pro-oncogenic stimulation is present. This could be a potential research line of interest in some cancerous risk patients taken into account that: (1) Complete occlusion of the main pancreatic duct could trigger a physiological protective effect to avoid malignancies in pancreas harboring Kras mutations without the aid of any other potentially dangerous treatments as it has been seen before; (2) This procedure could be feasible both surgically and endoscopically 53 ; (3) Kras mutations are believed to be a common initiator of mucinous lesions and other cancer precursor lesions 54 and (4) More than 90% of pancreatic adenocarcinomas harbor activating mutations in Kras for which targeted therapies have been notoriously ineffective across all cancer types prompting the perception that RAS is undruggable 54 . However, some limitations of this research must also be addressed: All the experiences were done in mice models in which early pancreatic lesions are evaluated after duct obstruction.…”

Computer Modeling for Radiofrequency Bipolar Ablation Inside Ducts and Vessels: Relation Between Pullback Speed and Impedance Progress

“…Blackline represents the mean values of the experiments ( n = 15), while green and blue lines show the computer results. In Model 2, the catheter body was assumed to have the characteristics of polyurethane [5–7], while in Model 1 the characteristics were estimated from measurements and assumptions (see text for details). ( B ) Temperature distributions for both models at 18 seconds (when the maximum temperature reaches 100°C in Model 2).…”

“…In this context, we recently proposed a similar endoductal RF ablation method to seal the pancreatic duct in the context of surgical management of the pancreatic stump after a pancreatectomy as an alternative to other mechanical methods (e.g., sutures, staplers, clips, or endoluminal glue injection) [7], the reason being that these methods continue to offer suboptimal results and have relatively high complication rates, especially the development of postoperative pancreatic fistula (POPF) [8]. From a technical point of view, our novel bipolar ablation method involves simultaneously dragging a catheter and transmitting RF power between the two electrodes.…”

“…The impedance progress measured between these two electrodes has been suggested as a control parameter to guide the procedure and is known to be related to pullback speed. Even though there are studies that claim high success rates in closing varicose veins [9] or sealing the pancreatic duct [7], there is also a recognized need for a better understanding of the relationship between applied power, pullback speed, and the created thermal lesion [10]. The long‐term goal is to optimize these procedures by implementing automatic pullback‐speed control guided by impedance progress.…”

Possible involvement of HSP70 in pancreatic cancer cell proliferation after heat exposure and impact on RFA postoperative patient prognosis

“…Although RFA has been widely used to treat solid tumors such as liver cancer [9,10] and colorectal cancer [11], since pancreatic tissue is sensitive to heat, rich in blood vessels, and the anatomical position is close to arteries and bile ducts, there's a high risk in applying thermotherapy technique. As RFA application becomes increasingly mature, the incidence of postoperative complications has decreased significantly [7,[12], [13], [14]]. A clinical survey in Italy pointed out that RFA can significantly eliminate pancreatic tumors, resulting in an average survival rate of 185 days [6].…”