Percutaneous unilateral placement of biliary covered metallic stent in patients with malignant hilar biliary obstruction and contralateral portal vein occlusion

ePTFE-based biomedical devices: An overview of surgical efficiency

Polytetrafluoroethylene (PTFE) is a ubiquitous material used for implants and medical devices in general because of its high biocompatibility and inertness: blood vessel, heart, table jawbone, nose, eyes, or abdominal wall can benefit from its properties in case of disease or injury. Its expanded version, ePTFE is an improved version of PTFE with better mechanical properties, which extends its medical applications. A material as frequently used as ePTFE with these exceptional properties deserves a review of its main uses, developments, and possibility of improvements. In this systematic review, we examined clinical trials related to ePTFE-based medical devices from the literature. Then, we excluded all trials using ePTFE as a control to test other devices. ePTFE-coated stents, hemodialysis and bypass grafts, guided bone and tissue regeneration membranes, hernia and heart repair and other devices are reviewed. The rates of success using these devices and their efficiency compared to other materials used for the same purposes are reported. ePTFE appears to be more or just as efficient compared to them. Some success rates remain low, suggesting the need of improvement ePTFE for medical applications.

Comparison of Unilateral With Bilateral Metal Stenting for Malignant Hilar Biliary Obstruction

PURPOSE

The main purpose of this study was to compare the clinical effectiveness between unilateral and bilateral metal stenting for malignant hilar biliary obstruction (MHBO).

METHODS

From January 2012 to October 2017, consecutive patients with MHBO underwent unilateral or bilateral stent insertion at our center. Technical and clinical success, stent patency, and survival were compared between these 2 groups.

RESULTS

A total of 110 patients with MHBO were included in this study. Technical successful rates of unilateral and bilateral stenting were 93.1% (54/58) and 90.4% (47/52), respectively (P=0.864). Clinical successful rates of unilateral and bilateral stenting were 96.4% (53/55) and 97.9% (46/47), respectively (P=1.000). There was no significant difference in stent patency period (unilateral, 182 d; bilateral, 198 d; P=0.999) and survival (unilateral, 189 d; bilateral, 199 d; P=0.867) between 2 groups.

CONCLUSIONS

Unilateral and bilateral metal stenting had similar clinical effectiveness and long-term outcomes in patients with MHBO.

Percutaneous Metallic Stent Placement for Palliative Management of Malignant Biliary Hilar Obstruction

Objective

To investigate the outcomes of percutaneous metallic stent placements in patients with malignant biliary hilar obstruction (MBHO).

Materials and Methods

From January 2007 to December 2014, 415 patients (mean age, 65 years; 261 men [62.8%]) with MBHO were retrospectively studied. All the patients underwent unilateral or bilateral stenting in a T, Y, or crisscross configuration utilizing covered or uncovered stents. The clinical outcomes evaluated were technical and clinical success, complications, overall survival rates, and stent occlusion-free survival.

Results

A total of 784 stents were successfully placed in 415 patients. Fifty-five patients had complications. These complications included hemobilia (n = 19), cholangitis (n = 13), cholecystitis (n = 11), bilomas (n = 10), peritonitis (n = 1), and hepatic vein-biliary fistula (n = 1). Clinical success was achieved in 370 patients (89.1%). Ninety-seven patients were lost to follow-up. Stent dysfunction due to tumor ingrowth (n = 107), sludge incrustation (n = 44), and other causes (n = 3) occurred in 154 of 318 patients. The median overall survival and the stent occlusion-free survival were 212 days (95% confidence interval [CI], 186-237 days) and 141 days (95% CI, 126-156 days), respectively. The stent type and its configuration did not affect technical success, complications, successful internal drainage, overall survival, or stent occlusion-free survival.

Conclusion

Percutaneous stent placement may be safe and effective for internal drainage in patients with MBHO. Furthermore, stent type and configuration may not significantly affect clinical outcomes.

Unilateral versus bilateral stent insertion for malignant hilar biliary obstruction

PURPOSE

To determine the clinical efficiency and long-term outcomes between unilateral and bilateral stent insertion in patients with malignant hilar biliary obstruction.

METHODS

From August 2012 to February 2016, 63 consecutive patients with malignant hilar biliary obstruction were treated with unilateral or bilateral stent insertion at our center. The bilateral stents were inserted using the side-by-side technique. The clinical efficiency and long-term outcomes were compared between the two groups.

RESULTS

Unilateral and bilateral stent insertions were successfully performed in 31 of 33 and 27 of 30 patients, respectively (P = 0.912). No procedure-related complication occurred. Clinical success was achieved in 29 of 31 patients in the unilateral stent group and in 26 of 27 patients in the bilateral stent group (P = 0.637). During the follow-up, re-obstruction of stent occurred in five patients in the unilateral stent group and in three patients in the bilateral stent group (P = 0.58). The significant differences were not observed in the stent patency time (368 vs. 387 days, P = 0.685) and survival (200 vs. 198 days, P = 0.751) between two groups. Based on the univariate and multivariate analyses, the independent risk factors for decreasing the survival time included higher Eastern Cooperative Oncology Group performance status (P = 0.018), higher alanine aminotransferase level (P = 0.009), and absence of anticancer treatment after stent insertion (P = 0.002).

CONCLUSION

Compared to bilateral stent insertion for malignant hilar biliary obstruction, unilateral stent insertion can provide comparable clinical efficiency and long-term outcomes.

Percutaneous unilateral biliary metallic stent placement in patients with malignant obstruction of the biliary hila and contralateral portal vein steno-occlusion

Objective

To investigate the outcomes of percutaneous unilateral metallic stent placement in patients with a malignant obstruction of the biliary hila and a contralateral portal vein steno-occlusion.

Materials and Methods

Sixty patients with a malignant hilar obstruction and unilobar portal vein steno-occlusion caused by tumor invasion or preoperative portal vein embolization were enrolled in this retrospective study from October 2010 to October 2013. All patients were treated with percutaneous placement of a biliary metallic stent, including expanded polytetrafluoroethylene (ePTFE)-covered stents in 27 patients and uncovered stents in 33 patients.

Results

A total of 70 stents were successfully placed in 60 patients. Procedural-related minor complications, including self-limiting hemobilia (n = 2) and cholangitis (n = 4) occurred in six (10%) patients. Acute cholecystitis occurred in two patients. Successful internal drainage was achieved in 54 (90%) of the 60 patients. According to a Kaplan-Meier analysis, median survival time was 210 days (95% confidence interval [CI], 135-284 days), and median stent patency time was 133 days (95% CI, 94-171 days). No significant difference in stent patency was observed between covered and uncovered stents (p = 0.646). Stent dysfunction occurred in 16 (29.6%) of 54 patients after a mean of 159 days (range, 65-321 days).

Conclusion

Unilateral placement of ePTFE-covered and uncovered stents in the hepatic lobe with a patent portal vein is a safe and effective method for palliative treatment of patients with a contralateral portal vein steno-occlusion caused by an advanced hilar malignancy or portal vein embolization. No significant difference in stent patency was detected between covered and uncovered metallic stents.

Outcomes of metallic biliary stent insertion in patients with malignant bilobar obstruction

PURPOSE

To assess clinical outcomes of metal stent insertion in patients with bilobar bile duct obstruction by malignant tumors.

MATERIALS AND METHODS

Records of 120 consecutive patients who underwent placement of metallic stents for palliation of malignant bilobar biliary obstruction between 1995 and 2010 were retrospectively reviewed. Single-duct stent insertion was performed in 44 patients with one liver lobe that accounted for more than 70% of total liver volume or only one patent lobar portal vein (group 1). Bilobar stent insertion was performed in 60 patients with approximately equal lobe sizes, patent lobar portal veins, or cholangitis at presentation (group 2). In 16 patients with discontiguous right anterior and posterior segmental ducts (group 3), three stents were deployed in the left lobar and right anterior and posterior segmental ducts. Overall survival, primary patency, and patient morbidity rates following stent insertion were assessed.

RESULTS

No significant differences in mean overall survival (group 1, 7.3 mo; group 2, 10.3 mo; group 3, 6.5 mo; P = .21) or mean primary stent patency (group 1, 4.2 mo; group 2, 5.9 mo; group 3, 3.5 mo; P = .17) were demonstrated. However, patients in group 3 were significantly more likely to require hospitalizations for cholangitis and additional invasive procedures for recurrent biliary obstruction than patients in groups 1 and 2.

CONCLUSIONS

Unilobar and bilobar metal stent insertion led to similar outcomes when treatment decision was based on relative liver lobe volumes, lobar portal vein patency, and presence of cholangitis on presentation.