Acute cholecystitis after stenting of the common bile duct for obstruction secondary to pancreatic cancer

Self-expandable metal stents in malignant biliary obstruction

Malignant biliary obstruction can be due to direct tumor infiltration, extrinsic compression, adjacent inflammation, desmoplastic reaction from tumors or, more commonly, a combination of the above factors. Pancreatic cancer is the most common cause of malignant biliary obstruction, and jaundice occurs in 70-90% of the patients during the course of the disease. Compared with the uncovered metal stents, covered metal stents have longer patency and a lower rate of tumor ingrowth, but have a higher rate of stent migration. To combat the occlusion and provide an antitumor effect, drug-eluting stents were developed. A duodenal stricture complicates biliary stent placement in 10-20% of patients with distal biliary obstruction due to pancreatic cancer. When both strictures are considered, a biliary stent can be placed either preceding or following duodenal stent placement. Complications of self-expandable metal stents include stent occlusion, stent migration, cholecystitis and pancreatitis.

Self-expandable metal stents for malignant distal biliary strictures

Obstructive jaundice can result from benign or malignant etiologies. The common benign conditions include primary sclerosing cholangitis, chronic pancreatitis, and gallstones. Malignant biliary obstruction can be caused by direct tumor infiltration, extrinsic compression by enlarged lymph nodes or malignant lesions, adjacent inflammation, desmoplastic reaction from a tumor, or a combination of these factors. Malignant diseases causing biliary obstruction include pancreatic cancer, ampullary cancer, cholangiocarcinoma, and metastatic diseases. This article focuses on malignant distal biliary obstruction and its management.

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.

Major early complications from diagnostic and therapeutic ERCP: a prospective multicenter study

BACKGROUND

There is a lack of multicenter prospective studies on complications of diagnostic and therapeutic endoscopic retrograde cholangiopancreatography (ERCP).

METHODS

We studied 2769 consecutive patients undergoing ERCP at nine centers in the Triveneto region of Italy over a 2-year period. Six centers performed ERCP on less than 200 patients per year (small centers). General and ERCP-specific major complications were predefined. Data were collected at the time of ERCP, before discharge, and in cases of readmission within 30 days. ERCP was defined as therapeutic when endoscopic sphincterotomy (n = 1583), precut (n = 419), or drainage (n = 701) had been carried out, singularly or in combination.

RESULTS

One hundred eleven major complications (4.0%) were recorded: moderate-severe pancreatitis 36 (1.3%), cholangitis 24 (0.87%), hemorrhage 21 (0.76%), duodenal perforation 16 (0.58%), others 14 (0.51%). Among 942 diagnostic ERCPs there were 13 major complications (1.38%) and 2 deaths (0.21%), whereas among 1827 therapeutic ERCPs there were 98 major complications (5.4%) and 9 deaths (0.49%). The difference in the incidence of complications between diagnostic and therapeutic ERCPs was statistically significant (p < 0.0001). Small center and precut were recognized as independent risk factors for overall major complications of therapeutic ERCP, whereas the following risk factors were identified in relation to specific complications: (1) pancreatitis: age less than 70 years, pancreatic duct opacification, and nondilated common bile duct; (2) cholangitis: small center, jaundice; (3) hemorrhage: small center; and (4) retroperitoneal duodenal perforation: precut, intramural injection of contrast medium, and Billroth II gastrectomy.

CONCLUSIONS

Major complications are mostly associated with therapeutic procedures and low case volume. Present data support a policy of centralization of ERCP in referral centers. A more selected and safer use of precut may be expected to further limit the adverse events of ERCP.

Endoscopic palliation for unresectable pancreatic carcinoma

Endoscopic stenting has revolutionized the palliation of malignant biliary obstruction. Individuals with biliary obstruction due to pancreatic malignancy are best managed by a team approach comprising individuals with expertise in oncology, surgery, endoscopy, and radiology. The clinical value of alleviating jaundice and associated symptoms of anorexia, pruritus, and malaise cannot be overestimated. These quality-of-life factors deserve more attention in future studies to define subgroups of patients most likely to derive benefit from the array of treatment options. Further technical improvements are required to solve the most important clinical problem of late stent occlusion. New developments such as expandable metallic stents and refinements in existing equipment and techniques have already resulted in measurable gains and hold great promise for future expansion of their use in malignant gastric outlet obstruction secondary to tumor infiltration of the duodenum. Corresponding advances are being made in the fields of percutaneous transhepatic intervention and hepatobiliary surgery such that further prospective randomized trials are necessary to define optimal therapy.

Endoscopic therapy for biliary obstruction

Endoscopic management of biliary obstruction is feasible in most patients and has emerged as standard treatment. Aside from the removal of bile duct stones, placement of a biliary stent is the most commonly employed modality of management. In experienced hands, this is successful in over 90% of patients. Lower procedure-related complications and the relative non-invasive nature of endoscopic treatment has relegated surgical management to a subsidiary role. Hospitalization time rarely exceeds 1-2 days. In most patients with advanced malignant disease and short life expectancy, stenting affords effective palliation. For the majority of patients endoscopic management is preferable to the percutaneous transhepatic approach due to lower overall mortality and morbidity. Stent occlusion necessitating replacement remains a problem, but improvements in this area can be expected. New plastic stent designs are undergoing investigation. Expandable metallic stents are promising but controlled comparative trials with conventional plastic prostheses are needed. Use of expandable stents should be judicious since these cannot be removed. In the future we can look forward to advances in peroral cholangioscopic technology which may permit targeted treatment of intraductal biliary malignancies.