Metal stents for distal biliary malignancy: have we got you covered?

Safety and Efficacy of Percutaneous Biliary Covered Stent Placement in Patients with Malignant Biliary Hilar Obstruction; Correlation with Liver Function

PURPOSE

To estimate the safety and efficacy of percutaneous ePTFE-covered biliary stent placement and the relationship between underlying liver function and stent patency in patients with malignant hilar obstruction.

MATERIALS AND METHODS

From March 2012 to June 2015, 41 patients [22 females, 19 males; mean age 69.8 (range 34-94) years] with malignant biliary obstruction underwent percutaneous biliary stent placement (31 patients with unilateral, 10 patients with bilateral side-by-side). Cumulative patient survival and stent patency rate curves were derived using the Kaplan-Meier method. A Cox model was used to explore the relationship between liver function and patient survival, and also biliary stent patency. Pearson correlation coefficient was used to analyze the relationship between patient survival and stent patency.

RESULTS

Technical success rate was 100 % and clinical success rate was 95 %. During follow-up, four complications occurred (two bilomas and two cases of acute cholecystitis) and were treated successfully with percutaneous drainage. No other complication occurred. Mean serum bilirubin level was 11.34 ± 7.35 mg/dL before drainage and 5.00 ± 4.83 mg/dL 2 weeks after stent placement. The median patent survival duration was 147 days (95 % CI, 69.6-224.4 days). The median stent patency duration was 101 days (95 % CI, 70.0-132.0 days). The cumulative stent patency rates at 1, 3, 6, and 12 months were 97, 57.6, 30.3, and 17.0 %, respectively. Child-Pugh score was correlated significantly with patient survival (P = 0.011) and stent patency (P = 0.007). MELD score was correlated significantly with stent patency (P = 0.044). There was a correlation between patient survival and stent patency (r = 0.778, P < 0.001).

CONCLUSION

Percutaneous placement of ePTFE-covered biliary stent was a safe and an effective method for malignant biliary obstruction. Underlying liver function seemed to be one of the important factors affecting patient survival and stent patency, and stent patency showed statistically significant correlation with patient survival.

Management of complications associated with partially covered biliary metal stents

BACKGROUND

Partially covered metal stents (PCMS) have been increasingly used for both malignant and benign biliary indications. This study reports their complications and subsequent management.

METHODS

Over 5 years, all patients receiving biliary PCMS were followed prospectively until stent-related dysfunction or death. Data were analyzed for the following variables: primary disease, time until revision, and type and reason for revision.

RESULTS

PCMS were placed in 396 patients (247 with malignant biliary strictures and 149 with benign biliary disease). Complications were observed in 70 patients (18%), occurring a mean time following placement of 159 days. Duodenal migration occurred in 27 cases (6.8%), while proximal migration occurred in 9 cases (2.3%). Cholecystitis was documented in 13 cases (3.3%). There were six cases of stent occlusion due to debris or sludge (1.6%), four cases of pancreatitis (1%), four cases of tumor overgrowth (1%), three cases of benign stenosis in the uncovered portion of the PCMS (0.8%), two cases of abdominal pain (0.5%), one case of an infected biloma (0.3%), and one case of a liver abscess (0.3%).

CONCLUSIONS

Major complications associated with PCMS placement include migration and cholecystitis. Their management includes endoscopic revision, cholecystectomy, and gallbladder drainage. Further improvements in the structure and composition of PCMS may prevent these complications.

Late Migration of Two Covered Biliary Stents Through a Spontaneous Bilioenteric Fistula in a Patient with Malignant Biliary Obstruction

We report a case of simultaneous late migration of two ePTFE-FEP covered biliary endoprostheses (Viabil, W.L. Gore, Flagstaff, AZ, USA) that were percutaneously implanted for the treatment of malignant obstructive jaundice. The first Viabil covered stent was placed successfully without any evidence of dislocation or other complication during follow-up. Occlusion of the stent occurred 4 months later and was treated with the placement of a second stent of the same type. Thirteen months later the patient became symptomatic. Percutaneous transhepatic cholangiography (PTC) revealed the presence of a choledocho-duodenal fistula and the disappearance of the two endoprostheses previously implanted. A third metallic stent was then percutaneously positioned through the bilioenteric fistula. The computed tomography scan that followed for the detection of the metallic bodies did not reveal the dislocated metallic stents. Stent migration is a well-known complication of uncovered metallic stents, though Viabil stent migration is assumed to be most unlikely to happen due to the stent's anchoring barbs. Furthermore, the stent had already been tightly fixed by tumor over- and ingrowth, as recognized in previous imaging. This is a very unusual case, describing the disappearance of two metallic foreign bodies encapsulated by tumor.

ePTFE/FEP-covered metallic stents for palliation of malignant biliary disease: can tumor ingrowth be prevented?

PURPOSE

To determine the application and clinical effectiveness of ePTFE/FEP-covered metallic stents for palliation of malignant biliary disease, and to evaluate the efficiency of stent coverage in preventing tumor ingrowth.

METHODS

During a 3-year period, 36 patients with malignant obstructive jaundice were treated with ePTFE/FEP-covered stents, with or without proximal side holes. The stricture was located in the lower common bile duct (CBD) in 18 cases, the upper CBD in 9, the lower common hepatic duct (CHD) in 6, and the upper CHD in 3 patients.

RESULTS

Thirty-seven covered stents were percutaneously implanted. The technical success rate was 97%. Reintervention was required in 6 cases. The 30-day mortality rate was 40%, not procedure-related. Mean survival was 128 days. Primary patency rates were 100%, 55.5%, and 25% at 3, 6, and 12 months, respectively, while the assisted patency rate was 100% at 12 months. Stents without side holes had higher primary patency rates compared with those with side holes, where occlusion was always due to tumor ingrowth. Tumor ingrowth did not occur in the completely covered stents. No stent dysfunction due to sludge incrustation was found. Complications were 1 case of arterial laceration that occurred during percutaneous transhepatic cholangiography, and a subcapsular hematoma and 1 case of bile peritonitis, that both occurred during primary stenting. No complications followed the secondary stenting technique.

CONCLUSION

ePTFE/FEP-covered metallic stents are safe and effective for palliation of malignant biliary disease. The presence of the ePTFE/FEP coating is likely to prevent from tumor ingrowth.

Risk factors for cholecystitis after metal stent placement in malignant biliary obstruction

BACKGROUND

Cholecystitis related to metal stent placement is a morbid event.

OBJECTIVE

This study evaluated the risk factors of cholecystitis after metal stenting for malignant biliary obstruction.

PATIENTS

Between December 1997 and April 2003, 155 patients who were treated with a metal stent for malignant biliary obstruction were retrospectively enrolled.

MAIN OUTCOME MEASUREMENTS

The incidence and characteristics of patients with cholecystitis were evaluated and compared with those of patients without cholecystitis. Patient characteristics and tumor or procedure-related data were recorded for the following variables: sex, age, tumor and stent length, stent type (covered vs uncovered), cholangitis before ERCP, degree of gallbladder filling with contrast medium during ERCP, primary disease type (Klatskin vs others), presence of gallbladder stones, and the relationship of the cystic duct orifice to the location of the tumor (across vs others).

RESULTS

There were 15 (9.7%) patients diagnosed with cholecystitis after metal stent insertion. The onset of cholecystitis was on average 4.6 days (range 1 to 26) after the procedure. We found that an obstruction across the cystic duct orifice by tumor (P < .01, odds ratio 12.7) and the presence of gallbladder stone (P = .01, odds ratio 6.6) were positively related to the cholecystitis after metal stent insertion.

LIMITATIONS

The limitations of the study were the use of multiple types of stents and the retrospective design.

CONCLUSIONS

This study demonstrated that an obstruction across the cystic duct by tumor and the presence of gallbladder stone were risk factors for the development of cholecystitis after metal stent placement.

Covered metal versus plastic stents for malignant common bile duct stenosis: a prospective, randomized, controlled trial

BACKGROUND

Most patients with malignant common bile duct strictures are suited only for palliation of jaundice by placement of a polyethylene (PE) stent using an endoscopic retrograde cholangiographic technique. Occlusion of these stents occurs after 3 to 4 months, whereas uncovered self-expanding metal stents (SEMS) remain open twice as long. The initial higher cost of the latter might be balanced by a decreased need for repeat intervention.

OBJECTIVE

To compare the patency of 10F PE stents and covered 30F steel SEMS (Wallstent; Boston Scientific Nordic AB, Helsingborg, Sweden).

DESIGN

Single-center, prospective, randomized, controlled trial.

SETTING

General hospital in Stockholm, Sweden, which has a catchment area of 0.6 million people.

PATIENTS

Non-referred, unresectable malignant common bile duct strictures.

INTERVENTIONS

Endoscopic retrograde cholangiography with plastic stents or covered SEMS.

MAIN OUTCOME MEASUREMENTS

Time to stent failure, requiring a new stent.

LIMITATIONS

Similar setting and patients, and costs in Scandinavia.

RESULTS

Fifty-one and 49 patients were allocated to the PE stent and SEMS groups, respectively. Fifty-six patients died without stent failure within 10 months (median, 2.6 months). Twenty-two PE stent and 9 SEMS patients (P = .009) developed failure after a median of 1.1 and 3.5 months, respectively (P = .007). Median patency times were 1.8 and 3.6 months in the PE and SEMS groups, respectively (P = .002). Median survival was 4.5 months; in 35 patients with distant metastases, the median survival was 2.5 months (P = .002)(PE group, 1.9 months).

CONCLUSIONS

The more-effective SEMS are recommended in unresectable patients with malignant common bile duct strictures, who survive a median of 4.5 months. Less costly plastic stents are preferable in the one third of patients who have distant metastases. In our study, the cost was equal.

Insertion and removal of covered expandable metal stents for closure of complex biliary leaks

The traditional endoscopic management of bile leaks involves placement of plastic endoprostheses. The success rate for closure of simple leaks (cystic duct, Luschka's duct) with this approach is high. We describe 3 patients with complex biliary leaks of the gallbladder bed that were successfully closed by using transpapillary placement of covered self-expandable biliary stents. The stents were endoscopically removed after closure of the leak. All 3 patients had previously undergone open subtotal cholecystectomy for severe acute cholecystitis when complete cholecystectomy could not be performed because of dense acute inflammation. In 2 patients the leaks had not responded to traditional plastic biliary stent placement. This novel approach deserves further evaluation.

Interventionen bei malignen Gallenwegstenosen

This paper gives an overview of experience and success of percutaneous transhepatic interventions in malignant biliary obstruction. Even after exhaustion of surgical and endoscopic therapy options, the percutaneously inserted stents provide effective palliation. The palliative treatment of malignant jaundice using a stent is an established procedure in clinical practice, particularly whenever the endoscopic, transpapillary approach is not possible due to high obstructions or previous surgery. The technical success rate is very high (about 95-100%), and the complication rate is about 10-30%. Since the patency rate of stents is higher than that of plastic endoprostheses, their primary use is justified despite higher costs, provided the patients are adequately selected.