Feasibility and Safety of Endoluminal Radiofrequency Ablation as a Rescue Treatment for Bilateral Metal Stent Obstruction Due to Tumor Ingrowth in the Hilum: A Pilot Study

Background. Radiofrequency ablation (RFA) is a palliative method known for its application in the endoscopic treatment of malignant bile duct obstruction. It may be a useful rescue method for metal stent malfunction caused by tumor ingrowth. This study aimed to examine the feasibility and safety of endoluminal RFA for occluded bilateral hilar metal stents due to tumor ingrowth in patients with malignant hilar bile duct obstruction. Methods: From March 2016 to June 2018, 11 patients with unresectable malignant hilar bile duct stricture with occluded bilateral hilar metal stents due to tumor ingrowth were enrolled. Endoluminal RFA was performed through a novel temperature-controlled catheter at a setting of 7 W power for 120 s with a target temperature of 80 °C via endoscopic retrograde cholangiopancreatography (ERCP). The patients’ demographics, clinical outcomes, and adverse events were investigated. Results: The median age was 64 (interquartile range, 54–72) years. All RFA procedures were successful. Clinical success was achieved in eight patients (72.7%). During the follow-up, eight patients (72.7%) showed stent dysfunction, and the median patency after RFA was 50 days (95% confidence interval (CI): 34–not available (NA)). All stent dysfunctions were successfully managed with ERCP. Ten patients died, and the median overall survival was 289 days (95% CI, 107–NA) from RFA to death. There was one case of mild abdominal pain after the procedure without serious adverse events. Conclusions: As a rescue therapy for occluded bilateral hilar metal stents due to tumor ingrowth, endoluminal RFA seemed to be safe and useful in selected patients.

Percutaneous stent-in-stent placement with large cell-type stents for malignant hilar biliary obstruction

Background To overcome the technical difficulty of bilateral stent-in-stent placement, large cell-type biliary stents have been developed. However, most of the studies using large cell-type stents were conducted with endoscopic method. Purpose To evaluate the efficacy and safety of percutaneous stent placement with a stent-in-stent method using large cell-type stents in patients with malignant hilar biliary obstruction. Material and Methods From December 2015 and October 2018, 51 patients with malignant hilar biliary obstruction were retrospectively studied. All of the patients underwent bilateral (n=46) or unilateral (n=5) stenting in a T, Y, or X configuration with a stent-in-stent method using large cell-type stents. Technical success, complications, successful internal drainage, stent patency, and patient survival were analyzed. Results A total of 118 stents were successfully placed in 51 patients (100.0%). Three patients had minor complications with self-limiting hemobilia. Major complications were not observed in any patient. Successful internal drainage was achieved in 45 patients (88.2%). Clinical follow-up information until death or the end of the study was available for 50 of 51 patients. The median patient survival was 285.5 days (95% confidence interval [CI] 197–374). Stent dysfunction occurred in 16 patients (35.6%) due to tumor ingrowth (n=9) or tumor ingrowth combined with biliary sludge (n=7) among the patients who achieved successful internal drainage. Median stent patency was 179 days (95% CI 104–271). Conclusion Percutaneous stent-in-stent placement with large cell-type stents is technically feasible and safe, and can be an effective technique in patients with malignant hilar biliary obstruction.

Etiopathogenesis of Trismus in Patients With Head and Neck Cancer: An Exploratory Literature Review

Trismus refers to a person’s inability to normally open his or her mouth. Trismus can occur as a symptom due to tumor ingrowth or it can occur postsurgical following the treatment for head and neck cancer. Radiation-induced trismus is also a relatively common oral complication. This review aimed at reviewing the etiopathogenesis of trismus in patients with head and neck cancer. Of the 16 publications included after final screening, of which one was a nonrandomized control trial, one a randomized control trial, 6 prospective cohort studies, and 8 retrospective cohort studies. Among them, 6 articles addressed the possible mechanism for trismus related to tumor ingrowth, 8 articles suggested the likely reason for trismus in patients who had undergone radiation therapy and 2 articles addressed the postsurgical cause for trismus. This review highlights the possible involvement of infratemporal fossa as a predetermining factor for developing trismus related to tumor extension. The molecular mechanism of radiation-induced fibrosis is well studied in the literature.

Covered vs. uncovered self-expandable metal stents for malignant distal biliary strictures: a systematic review and meta-analysis

Background Self-expandable metal stents (SEMS) are used for palliation of distal malignant biliary strictures, but the role of covered SEMS is less clear. We performed an up-to-date meta-analysis to compare the performance of covered and uncovered SEMS in patients with unresectable distal malignant biliary strictures. Methods A computerized medical search was performed using MEDLINE, EMBASE, and the Cochrane Library between 2000 and December 2016 to identify all randomized trials that compared covered with uncovered SEMS in patients with distal malignant biliary strictures. Primary outcomes were stent failure and patient mortality; secondary outcomes were stent dysfunction and adverse events. Pooled estimates were computed using the random effects model. Results Overall, 11 RCTs involving 1272 patients were included. The primary outcomes of stent failure and patient mortality did not differ significantly between covered and uncovered SEMS (hazard ratio [HR] 0.68, 95 % confidence interval [CI] 0.40 – 1.17; HR 0.89, 95 %CI 0.76 – 1.05, respectively). However, stent migration and sludge formation were much more common with covered SEMS (odds ratio [OR] 5.11, 95 %CI 1.84 – 14.17; OR 2.46, 95 %CI 1.37 – 4.43). The use of covered SEMS was associated with a lower rate of tumor ingrowth (OR 0.21, 95 %CI 0.09 – 0.50) but a higher rate of tumor overgrowth (OR 2.00, 95 %CI 1.15 – 3.48) compared with uncovered stents. The rates of procedure-related adverse events were similar in both groups. Conclusion There was a risk reduction of about 32 % for both stent failure and patient mortality with covered SEMS but this difference was not significant. Migration and sludge rates were higher with covered SEMS, whereas tumor ingrowth was more likely with uncovered SEMS. The data show no added benefit of covered SEMS; further stent evolution is desirable.

Side-by-side partially covered self-expandable metal stent placement for malignant hilar biliary obstruction

Background and study aims This study investigated the feasibility of side-by-side (SBS) partially covered self-expandable metal stent (PCSEMS) placement for unresectable malignant hilar biliary obstruction (MHBO). Patients and methods We retrospectively analyzed 33 patients from a single center who underwent endoscopic biliary drainage for unresectable MHBO from July 2013 to June 2015. In all patients with bilateral obstruction during complete bilateral intrahepatic cholangiograms, we performed endoscopic SBS placement of a 6-mm diameter PCSEMS using an 8-French delivery system. All patients underwent endoscopic sphincterotomy. Generally, patients with recurrent biliary obstruction (RBO) after stent placement underwent endoscopic reintervention. Our study outcomes included the technical and functional success rates, RBO rate, time to RBO (TRBO), reintervention rate, and incidence of adverse events. Results Seventeen patients with unresectable MHBO during complete bilateral intrahepatic cholangiograms underwent endoscopic SBS PCSEMS placement (median age, 78 years; men, 9). Lesions were Bismuth types II (n = 10), III (n = 1), and IV (n = 6), including 10 cholangiocarcinomas, 3 gallbladder cancers, and 4 metastatic cancers. In all patients, the PCSEMS was placed across the duodenal papilla. The technical and functional success rates were 100 % and 82 %, respectively. The median procedure time was 43 minutes (interquartile range [IQR]: 36 – 52 minutes). Twelve patients had RBO (71 %), including 9 stent occlusions due to sludge and 3 stent migrations. The median TRBO was 79 days (IQR: 58 – 156 days) during the follow-up period (median 192 days [IQR: 88 – 551 days]). The median TRBO of patients with Bismuth type II lesions was significantly longer than that of patients with Bismuth types III and IV lesions (87 days [IQR: 70 – 244 days] vs. 54 days [IQR: 35 – 100 days]; P = 0.030). Thirteen patients (76 %) required endoscopic reintervention. Endoscopic stent removal was possible in 6 patients without tumor ingrowth into the uncovered distal part of the stent. One late adverse event (≥ 31 days) occurred (cholangitis). Conclusions Endoscopic SBS placement of a PCSEMS was feasible in patients with unresectable MHBO. Additionally, reinterventional stent removal was possible in the absence of tumor ingrowth.