INTRODUCTION
Malignant obstructive jaundice is caused by primary biliary tract malignancies, such as cholangiocarcinoma or metastatic tumors, which leads to significant morbidity[1]. The clinical manifestation includes jaundice, pruritus, and systemic complications like cholangitis and coagulopathy. Effective biliary drainage is essential for symptom relief, particularly in those ineligible for curative surgery. Endoscopic biliary stenting has emerged as a minimally invasive means to restore bile flow and reduce jaundice. Endoscopic biliary stenting is typically performed via endoscopic retrograde cholangiopancreatography. Compared with percutaneous biliary drainage (PBD), endoscopic biliary stenting exhibited distinct advantages. However, the management remains complex, necessitating patient selection and technical approaches. This article is aimed to provide a comprehensive overview of endoscopic biliary stenting for malignant obstructive jaundice, exploring its pathophysiological basis, technical nuances, impact on quality of life (QoL), comparative efficacy with other methods, and future advancements in stent design (Figure 1).
Figure 1 Overview of endoscopic biliary stenting in malignant obstructive jaundice.
PATHOPHYSIOLOGY OF MALIGNANT BILIARY OBSTRUCTION
Malignant biliary obstruction can be driven by malignant transformation of epithelial cells in the bile ducts, influenced by a combination of genetic, inflammatory, and environmental factors. Chronic inflammation plays a key role in the pathogenesis of malignant biliary obstruction, particularly in patients with primary sclerosing cholangitis and hepatitis B. The persistent inflammation promotes tumor development and progression through the formation of a dense fibro-inflammatory stroma that supports malignant growth[2]. The tumor microenvironment also contributes significantly to tumor progression and invasion. Tumor-associated macrophages promote tumor invasiveness, while neuroendocrine regulation of cholangiocyte function contributes to cholestasis and cholangiocarcinoma growth[3]. These changes lead to clinical symptoms with systemic effects complicating patient management[4]. The underlying mechanisms provide the basis for interventions such as endoscopic biliary stenting, which aims to alleviate symptoms and improve bile flow.
TECHNICAL ASPECTS OF BILIARY STENTING
Endoscopic biliary stenting is a crucial intervention in the management of malignant biliary obstruction. The choice of stenting technique depends on the characteristics of the obstruction, including its location and extent, as well as the patient’s overall condition. Endoscopic retrograde cholangiopancreatography is often the preferred method for distal obstructions due to its minimally invasive nature and effectiveness in reducing complications. For more complex hilar obstructions, PBD may be more suitable as it allows for targeted bile duct drainage while reducing the risk of enteric contamination[5]. Two common stenting approaches for hilar obstructions include side-by-side and stent-in-stent, with side-by-side generally associated with quicker jaundice relief and longer stent patency[6]. The choice between self-expanding metal stents (SEMS) and plastic stents is also important. SEMS are often preferred for patients with longer life expectancy due to their superior patency and lower rate of reintervention, while plastic stents may be suitable for short-term palliation[7]. Recent advancements such as 3-dimensional (3D)-printed stents offer better adaptability to patient-specific anatomy, reducing complications such as migration or occlusion[8]. Effective diagnosis and planning for stenting procedures require high-quality imaging to determine the level and nature of the obstruction[9]. A multidisciplinary approach involving gastroenterologists, radiologists, and oncologists is vital to ensure successful intervention[10].
PATIENT SELECTION AND COMPARISON WITH PBD
The selection of patients for endoscopic biliary stenting is critical for optimizing treatment outcomes. Patients with distal malignant obstructions are generally more suitable for endoscopic stenting due to its high success rate and lower risk of complications, whereas hilar obstructions are more challenging and often require percutaneous approaches. The Bismuth-Corlette classification is used to assess hilar strictures and guide decision-making for the appropriate stenting strategy. Endoscopic stenting is associated with shorter hospital stays and fewer adverse events, while PBD is frequently used in high-grade hilar obstructions where endoscopic access is challenging[11]. Liver function improvement following either technique is generally comparable[12]. In terms of complications, endoscopic stenting is linked to a higher incidence of pancreatitis, whereas PBD tends to have higher rates of bleeding and tube dislocation[13]. Tumor seeding refers to the spread of cancer cells along the path of the procedure, which can occur when instruments like catheters or stents are introduced into or around malignant areas. In the context of tumor seeding, PBD has been associated with a higher risk compared to endoscopic biliary stenting. PBD, due to the need for a percutaneous needle or catheter insertion through the skin, can result in the inadvertent spread of malignant cells along the needle track, especially in cases of tumors that are close to the liver surface or in patients with advanced malignancy. This complication is a well-known risk in percutaneous procedures. In contrast, endoscopic stenting carries a lower risk of tumor seeding because it is performed through the gastrointestinal tract, which generally avoids direct puncture through or near the tumor mass. However, it’s not entirely without risk, particularly in cases where there is a direct connection between the biliary system and the tumor mass. The choice between endoscopic stenting and PBD should be individualized based on tumor location, patient anatomy, and treatment goals.
IMPACT OF ENDOSCOPIC BILIARY STENTING ON QOL
QoL is a key consideration in the palliative management of malignant obstructive jaundice. Soomro et al[14] reported an increase in QoL scores from 71.47 to 84.12 within 30 days of intervention. Specifically, internal-external biliary-jejunal drainage tends to yield better physical outcomes compared to endoscopic retrograde biliary stenting, although endoscopic retrograde biliary stenting still provides significant symptomatic relief[15]. However, complications impact overall QoL despite the high technical success rate of up to 98% for SEMS[16]. These challenges underscore the importance of careful patient selection and management to minimize adverse outcomes.
FUTURE ADVANCES IN STENTING
Future advancements in stenting hold significant promise for improving patient outcomes. Bioresorbable stents are being developed to reduce the need for repeat procedures, while 3D-printed stents offer personalized designs to better fit patient-specific anatomy, thereby minimizing migration risks[17]. 3D printing is one of the most exciting advancements in endoscopic stenting, with the potential to revolutionize the design and application of stents. 3D printing allows for the creation of stents that are customized to the specific anatomy of a patient. This would minimize complications related to ill-fitting stents, such as migration or obstruction, and optimize the clinical outcomes. 3D printing technology can also be used to create drug-eluting stents, which slowly release therapeutic agents to the surrounding tissue. This can be particularly beneficial in preventing tumor progression, reducing the risk of infection, or minimizing post-procedure inflammation. Drug-eluting stents and radioactive stents are designed to release localized therapies directly at the site of obstruction, potentially enhancing stent patency and patient survival[18]. While endoscopic biliary stenting is generally considered safe, it is not without risks. Endoscopic stenting, particularly in the context of biliary obstruction, is associated with a higher incidence of post-procedure pancreatitis. This complication occurs more frequently when the bile duct is closely associated with the pancreatic duct, or when stenting is performed through the ampulla of Vater. Besides, migration of the stent out of the biliary duct is a significant complication. Infection is one of the most serious complications of biliary stenting and can occur due to bacterial colonization of the stent, especially if the stent is left in place for long periods. Over time, stents can also become occluded by bile sludge, pus, or tumor tissue, leading to recurrent jaundice or cholangitis. This is more common with plastic stents, but can also occur with metal stents in some cases. The future of endoscopic stenting looks promising, with innovations such as 3D printed stents. The personalization of stent designs, especially for patients with complex anatomy, could significantly reduce complications and improve outcomes. These innovations are expected to further enhance the role of endoscopic stenting in the management of malignant obstructive jaundice, improving both QoL and overall treatment success[19].
CONCLUSION
Endoscopic biliary stenting is important in the palliative management of malignant obstructive jaundice, offering a minimally invasive solution to alleviate symptoms, improve bile flow, and enhance patient QoL. The selection of patients for endoscopic biliary stenting is critical for optimizing treatment outcomes. Endoscopic biliary stenting may improve QoL. The future of endoscopic biliary stenting looks promising, offering hope for enhanced patient survival and more effective palliation in this challenging disease.
Provenance and peer review: Invited article; Externally peer reviewed.
Peer-review model: Single blind
Specialty type: Gastroenterology and hepatology
Country of origin: China
Peer-review report’s classification
Scientific Quality: Grade B, Grade B, Grade C, Grade D
Novelty: Grade B, Grade C, Grade C, Grade D
Creativity or Innovation: Grade B, Grade B, Grade C, Grade C
Scientific Significance: Grade B, Grade B, Grade B, Grade C
P-Reviewer: Anandan H; Demirli Atici S; Shukla A S-Editor: Wei YF L-Editor: A P-Editor: Zheng XM
