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ENDOSCOPIC MANAGEMENT OF MALIGNANT BILIARY OBSTRUCTION
PARIJAT A GUPTE
Jagjivanram Western Railway Hospital, Mumbai Central.
INTRODUCTION
Extrahepatic obstruction of the biliary tract is associated with poor outcome. Curative resection is possible in only 15-20% cases except ampullary tumours. Endoscopic management forms the mainstay of the treatment. It scores over surgery and percutaneous methods in comparable success, and favourable mortality and morbidity rates.[1-3]
GENERAL CONCEPTS
Indications
Preoperative Stenting : Randomised trials and recent retrospective studies have not shown any advantage in preoperative biliary tract decompression.[4,5] It is recommended only in exceptional circumstances such as : 1. Cholangitis, 2. major pruritus, 3. General condition temporarily contraindicating surgery, 4. Incidental discovery during endoscopic retrograde cholangiography(ERC) with suprastenotic opacification ( to prevent iatrogenic cholangitis).[6]
Palliative : Palliation in inoperable cases is indicated for pruritus and cholangitis. It also improves the appetite and malabsorption. Endoscopic therapy is based on use of plastic or metal stents as biliary endoprosthesis.
AETIOLOGY AND MANAGEMENT
1. Distal common bile duct stictures : Aetiology 1) Carcinoma head of pancreas; 2) metastasis to peripancreatic lymph nodes; 3) Ampullary Carcinoma; 4) Distal cholangiocarcinoma
Endoscopic approach with self-expandable stent placement is the preferred method of palliation in this region, unless associated with very limited life expectancy due to peritoneal carcinomatosis, diffuse hepatic metastasis or high ASA score.
In distal common bile duct strictures with deformed duodenum ( seen in advanced pancreatic head malignancy), endoscopic biliary stenting followed by duodenal stenting avoids double bypass surgery for palliation. If biliary stenting is not possible then percutaneous bilary stenting may be followed by duodenal stenting.
2. Proximal common bile duct and common hepatic duct strictures : Aetiology : 1)Carcinoma Gall bladder; 2) Cholangiocarcinoma; 3) Metastasis to lymph nodes
Endoscopic metal or biliary prosthesis is the preferred choice. If endoscopic approach fails, percutaneous transhepatic cholangiography (PTC)and stent internalisation can be done.
3. Hilar strictures : Aetiology : Most commonly, hilar cholangiocarcinoma (Klatskin Tumour)
ERC and stent placement is associated with low technical success and high procedure related morbidity and mortality. Overall complication rates of 27-49% have been reported with median survival of 6 months.[11]
This is mainly due to bacterial cholangitis (17-49%) resulting from dye injection during ERC and inadequate drainage of the dye following cholangiogram.
Plastic stents Metal stents Material Polyethylene/teflon Steel/ Nitinol( Nickel,Titanium) size: 7F to 11.5 F 10 mm ( 30F) Technique: ERC+sphincterotomy Stent passed over guide wire with the help of pusher behind. ERC+sphincterotomy
Assembly of delivery device and constrained stent, passed over wire.Techical success : Hilar -70%
Subhilar -90%(6)
95% Pre and post deployment diameter is the same Opens to it's full dimeter in 24 to 48 hours. Patency rate : 4-5 months (7/8) Patency : 9-11 months Clogging by biofilm and sludge formation (8/9) Clogging by tumour ingrowth and tissue hyperplasia. Retrievable and can be exchanged Non retrievable. Recanalisation by stent exchange. Recanlisation by additional plastic or metal stent in existing stent. Cheap, Cost effective if survival < 6 months.[10] Costly, Cost effective if survival > 6 months.
Stenting of the hilar strictures is accomplished easily by percutaneous technique.[12] Multiple stents can be put in different ducts to achieve a better drainage. Percutaneous approach also involves complications like haemorrhage, biliary leaks and infections at puncture sites. In absence of cholangitis, drainage of single duct achieves adequate drainage. Left duct is preferred over the right for stenting as it has lesser branches near the hilum and achieves long term palliation.
In earlier studies bilateral stent placement was superior to unilateral stenting after previous bilateral ERC. Its improved survival and reduced cholangitis is due to better drainage with bilateral stenting.[13]
Recently magnetic resonance cholangiopancreatography (MRCP) has revolutionised the technique of biliary tract imaging. With pre-therapeutic MRCP, it is possible to stratify patients according to the extent of bile duct involvement without risk of injecting contrast. Hintze et al in a recent study showed early cholangitis rates as low as 6% with one year survival 48% following unilateral stenting in an MRCP selected radicle in Bismuth type 3 and 4 hilar tumours.[14]
Diameter 8F x 10F x 11.5F 10F better than 8F /No advantage in stents larger than 10F(17/18) Material To reduce coefficient of friction Stents coated with hydromer- no improved patency.[19] Design Reduce the turbulence
During bile flow
Tanenbaum stent ( no side holes) .
no improved patency[20]Antibiotic impregnation prophylaxis. To reduce cholangitis,
biofilm formation
Contradictory results in trials.[21] UDCA± Quinolones To reduce infection and sludge Contradictory results Stent exchange
(Elective x As necessary)
To reduce cholangitis Elective exchange at 3 months reduces complications and stay in the hospital.[10]
COMPLICATIONS
Early : Sphincterotomy related : Pain, pancreatits , haemorrhage and occasionally perforation.
Early cholangitis is seen with similar frequency in plastic (8.9%) and metallic stents (12.2%).[8] Aetiology of early cholangitis is inadequate drainage, Incorrect stent position, early migration and early obstruction due to growth or sludge.
Acute cholecystitis is seen in 0.1 to 1.6% cases following biliary endoprosthesis.[15,16] This is due to blockade of the cystic duct due to stent in early period and later due to extension of the tumour to block the duct opening. This can be managed by cholecystectomy or cholecystostomy.
Late : Stent Blockade : Clogging of the stent is the major complication in later stages. It presents with recurrence of jaundice or cholangitis. Plastic stents get blocked due to formation of biofilm formed of mucoproteins , bacteria and sludge (calcium bilirubinate and palmitate).
Metal stents get clogged due to tumour ingrowth and tissue hyperplasia. Covered biliary stents reduce the ingrowth through the interstices of the mesh. Covered stents are more liable for migration. Chance of blocking the cystic duct or other branches are high with covered stents.
Other complications include migration and delayed cholangitis due to stent blockade.
A short term follow up of endoscopically managed malignant biliary obstructions (January 1997-June 2001) at our centre showed palliation could be achieved in 87% (54/62) of the patients with 7f/10f teflon stents. The incidence of cholangitis was seen in 7%. There was no procedure related mortality.
of plastic stents at papilla
stent (Distal end at papilla)
stents for hilar stricture
by multiple plastic stents
both common hepatic ducts
Recent advances
1. Endoscopic photodynamic therapy for unresectable cholangiocarcinoma has shown improved palliation and increased patient survival.[22]
2. Plastic stents coated with carboplatin, for cholangiocarcinoma showed partial response in a small study.[23]
3. Intraductal high intensity therapeutic ultrasound during ERCP for palliation.[24]
4. Argon plasma coagulation for cutting the mesh of the metal stents in case of malpositioning.[25]
REFERENCES
1. Anderson JR, et al. Randomised trial of endoscopic endoprosthesis versus operative bypass in malignant obstructive jaunduce. Gut 1989; 30 : 1132-1135.
2. Smith AD, et al. Randomised trial of endoscopic stenting versus surgical bypass surgery in malignant low bile duct obstruction. Lancet 1994; 344 : 1655-60.
3. Speer AC, et al. Randomised trial of endoscopic versus percutaneous stent insertion in malignant obstructive jaundice. Lancet 1987; ii : 57-62.
4. Khyrim K, et al. Prospective randomised controlled trial of metal stents for malignant obstruction of common bile duct. Endoscopy 1993; 25 : 207-212.
5. Marignoni ME, et al. Effect of preoperative biliary drainage on surgical outcome after pancreatoduodenectomy. Am J Surg 2001; 181 : 52-59.
6. Rey JF, et al . Guidelines of the french society of digestive endoscopy : Billiary stenting. Endoscopy 2002; 34 (2) : 169-173.
7. Libby ED, et al. Prevention of stent clogging : A clinical review. Am J Gastroenterol 1996; 91 (7) : 1301-1308.
8. Davids PH, et al. Randomised trial of self expanding metal stents versus polyethylene stents for distal malignant biliary obstructon. Lancet 1992; 340.
9. Gore AK, et al. Characterisation of the content of occluded biliary endoprosthesis. Endoscpy 1987; 19 : 57-59.
10. Prat F, et al. A randomised trial of endoscpoic drainage for inoperable malignant strictures of commonbile duct .Gastrintest endosc 1998; 47 : 1-7.
11. Fiueras, et al. resection as elective treatment of hilar cholangiocarcinoma.Gastroenterol hepatol 1998; 21 : 218-23.
12. Aherndt SA, et al. Current mangement of patients with perihilar cholangiocarcinoma. Adv Surg 1996; 30 : 427.
13.Peters RA, et al. The mangement of high grade hilar stricture by endoscopic insertion of self expandable metal stent. Endoscopy 1997; 29 : 102-106.
14. Hihtze RE, et al. Magnetic resonance cholangiopancreatogrphy guided unilateral endoscopic stent placement for Klatskin tumor. Gastrointest.Endosc 2001; 53 : 40-46.
15. Lopeerfidos, et al. Earky comlications from diagnostic and therapeutic ERCP. Gastrointest Endosc 1998.
16. Ainlyecc, et al. Gall bladder sepsis following stent insertion for bile duct obstruction -managemet by percutaneous cholecysostomy. Br J Surg 1991; 78 : 961-3.
17. Speer AC, et al. Endoscopic management of malignant biliary obstruction : stents of 0 french guage are preferred to stents of 8 french guage. Gastrointest Endosc 1988; 34 : 412-17.
18. Kadakia SC, et al. Comparison of 10 F guage stent with 11.5 F guage stent in patients with biliary tract diseases. Gastrointest Endosc 1992; 38 : 454-59.
19. Costamagna G, et al. Hydrophillic polymer coated polyurethane stents in malignant biliary obstruction. Endoscopy 2000; 51 : 8-11.
20. Terruzi V, et al. prospective randomised trial of Tanenbaum teflon stents Versus traditional polyethylene stents in malignant biliary stenosis. Gastrintest Endosc 1997; 54 : 45,AB151.
21. Shah SK, et al. Theraputic biliary endoscopy. Endoscopy 2002; 34 (1) : 43-53.
22. Rumalla A, et al. Endoscopic application of photodynamic therapy for cholangiocarcinoma. Gastrointest Endosc 2001; 53 : 500-4.
23. Mezwa S, et al. A study of carboplatin coated tube for the unresectable cholangiocarcinoma. Hepatology 2000; 32 : 916-23.
24. Prat F, et al. Destruction of a bile duct carcinoma by intrductal high intensity ultrsound during ERCP. Gastrointet Endosc 2001; 53 : 797-800.
25. Dearquay JF, et al. Argon plasma endoscopic section of biliary metallic prosthesis. Endoscopy 2002; 33 : 289-90.
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