Metallic Stent Placement In Patients Research Articles

Embolization for delayed arterial bleeding after percutaneous self-expandable metallic stent placement in patients with malignant biliary obstruction.

To retrospectively evaluate the safety and efficacy of transcatheter arterial embolization (TAE) for delayed arterial bleeding secondary to percutaneous self-expandable metallic stent (SEMS) placement in patients with malignant biliary obstruction (MBO). From January 1997 to September 2017, 1858 patients underwent percutaneous SEMS placement for MBO at a single tertiary referral center. Among them, 19 patients (mean age, 70.2 [range, 52-82] years; 13 men) presented with delayed SEMS-associated arterial bleeding and underwent TAE. The incidence of delayed arterial bleeding was 1.0% (19/1858) after SEMS placement, with a median time interval of 225 days (range, 22-2296). Digital subtraction angiography (DSA) showed pseudoaneurysm alone close to the stent mesh (n = 10), pseudoaneurysm close to the stent mesh with contrast extravasation to the duodenum (n = 3), pseudoaneurysm close to the stent mesh with arteriobiliary fistula (n = 1), in-stent pseudoaneurysm alone (n = 4) and in-stent pseudoaneurysm with arteriobiliary fistula (n = 1). Bleeding was stopped after the embolization in all patients. Overall clinical success rate was 94.7% (18/19). One patient with recurrent bleeding was successfully treated with a second embolization. Overall 30-day mortality rate was 26.3% (5/19). A major procedure-related complication was acute hepatic failure in one hilar bile duct cancer patient (5.3%), which was associated with an obliterated portal vein. TAE is safe and effective for the treatment of delayed arterial bleeding after percutaneous SEMS placement for MBO. This study demonstrated TAE is safe and effective for arterial bleeding after SEMS placement after MBO through the largest case series so far.

Central venous occlusion in hemodialysis access: Comparison between percutaneous transluminal angioplasty alone and nitinol or stainless-steel stent placement

PurposeThe purpose of this study was to compare the primary and secondary patency rates of percutaneous transluminal angioplasty (PTA) alone with those of metallic stent placement in patients with hemodialysis access and central venous occlusion (CVO) and to compare the respective effects of nitinol and stainless-steel stents on patency. Materıals and methodsA total of 150 consecutive patients with hemodialysis access who underwent endovascular treatment for symptomatic CVO with ipsilateral functioning hemodialysis access were evaluated. There were 67 men and 83 women with a mean age of 56.2±15.2 (SD) years (range: 15–86 years). The primary endovascular treatment of CVO was PTA alone. Stent placement either with nitinol or stainless-steel stents was performed as a bailout procedure. The results were analyzed on a per patient basis. ResultsTechnical success was achieved in 141/150 patients (94%). Of the 141 patients, 109 (77%) underwent PTA alone and 32 (23%) underwent stent placement. The mean number of interventions in the stent group [4.3±2.5 (SD)] was significantly higher than that in the PTA alone group [2.6±2.8 (SD)] (P=0.002). The primary patency rates at 12, 24, and 60 months for the stent group (58.7%, 41.9%, and 27.9%, respectively) were significantly higher than those in the PTA alone group (42.4%, 36.3%, and 20.2%, respectively) (P=0.036). Secondary patency rates at 12, 24, and 60 months for the stent group (87.6%, 80.7%, and 50.3%, respectively) were significantly greater than those in the PTA alone group (68.4%, 56%, and 38.6%, respectively) (P=0.046). Furthermore, the primary patency rates at 6 and 12 months in the nitinol stent group (89% and 80.9%, respectively) were significantly greater than those in the stainless-steel stent group (78.8% and 38.4%, respectively) (P=0.007). The secondary patency rates at 6, 12 and 24 months for the nitinol stent group (92.8%, 87.7% and 65.8%, respectively) were significantly greater than those in the stainless-steel stent group (85.7%, 76.2% and 65.3%, respectively) (P=0.011). ConclusıonAlthough PTA alone is an effective interventional treatment strategy of CVO in short term, stent placement yields greater primary and secondary patency rates in the long-term. But the mean number of interventions per vein after stenting is significantly higher. Close follow-up and multiple re-interventions are necessary to ensure long-term patency.

Sa1274 EFFECT OF ENDOSCOPIC TRANSPAPILLARY METALLIC STENT PLACEMENT WITH/ WITHOUT ENDOSCOPIC SPHINCTEROTOMY ON POST-ERCP PANCREATITIS IN PATIENTS WITH MALIGNANT BILIARY OBSTRUCTION

Effect of endoscopic sphincterotomy (ES) prior to metallic stent (MS) placement in patients with distal malignant biliary obstruction (MBO) to prevent post-ERCP pancreatitis (PEP) remains to be fully elucidated, because the safety of non-adding ES for the cases without main pancreatic obstruction is unclear. To evaluate the efficacy and safety of non-adding ES prior to MS placement in patients with distal MBO, including those without MPD obstruction. Between January 2006 and August 2017, 285 patients with distal MBO were treated with MS placement in our tertial referral center, of which 74 were excluded because of a former history of ES, and/or prior MS placement. Finally, 211 patients were retrospectively enrolled in this study. Sixty-nine patients underwent ES just before MS placement (ES group), whereas 142 underwent MS placement without ES (non-ES group). We evaluated (1) the patients’ characteristics, (2) the incidence of PEP within 2 days after the procedure, (3) the incidence of bleeding, cholangitis, cholecystitis, and perforation within 30 days after the procedure, and (4) the effect of ES/ non-ES on the time to MS dysfunction. (1) Sex (man): ES, 40; non-ES, 83 (p = 0.947). Age (median): ES, 71 (range, 11–89); non-ES, 67 (range, 43–90) (p = 0.659). The etiology of MBO (bile duct cancer/ gall bladder cancer/ lymph node metastasis/ pancreatic cancer/ ampullary cancer): ES, 12/4/12/41/0; non-ES, 14/3/12/107/6 (p = 0.018). MPD obstruction: ES, 43; non-ES, 117 (p = 0.019). (2) PEP occurred in 11 patients in the ES group and in 20 in the non-ES group (p = 0.721). Among the patients without MPD obstruction (26 in the ES group and 25 in the non-ES group), PEP occurred in 10 patients in the ES group and in five in the non-ES group (p = 0.148). (3) Bleeding was significantly higher in the ES group (three patients) than in the non-ES group (zero patient, p = 0.034). Further, the incidence of cholangitis (four vs. five patients, p = 0.13), cholecystitis (four vs. four patients, p = 0.497), and perforation (zero patient in both) in the ES and non-ES groups, respectively, was not significantly different. (4) The median follow-up periods in the ES and non-ES groups were 191 (range, 14–999) and 204 (range, 12–1846) days, respectively. MS dysfunction was observed in 15 and 30 patients in the ES and non-ES groups, respectively (p = 0.919). The median time to MS dysfunction in the ES and non-ES groups was 145 (range, 6–465) and 114 (range, 2–759) days, respectively (p = 0.803). The study concluded that performing ES prior to MS placement for distal MBO does not reduce the incidence of PEP, but elevates the risks of bleeding related to ES. Hence, routine ES should be avoided prior to MS placement for distal MBO.

Abstract No. 636 A large-bore uncovered metallic stent for the treatment of malignant superior vena cava syndrome

To investigate the safety and efficacy of large-bore uncovered metallic stent placement in patients with malignant superior vena cava (SVC) syndrome. Between August 2015 and December 2016, 27 consecutive patients (24 men and 3 women; mean age, 64.3 years; range, 52-80 years) with malignant SVC syndrome were retrospectively reviewed. All patients were treated with a large-bore uncovered metallic stent (20-30 mm in diameter). The size of stent was chosen based on the diameter of 15-25% larger than the SVC. The mean diameter of SVC and brachiocephalic vein (BCV) were 18.3 mm and 14 mm, respectively. Stent placement was technically successful in all 27 patients. The mean diameter of the stent was 24 mm. Any overstretching nor overdistension of SVC and BCV was not observed. There were no major complications. The pressure gradient, which was 18.9 ± 8.0 mm Hg before stent placement, dropped significantly to 4.3 ± 3.0 mm Hg after stent placement (p<0.001). Of the 25 patients symptomatic prior to stent placement, 23 (92%) experienced complete symptomatic relief 1-6 days after stent placement. The median patient survival and stent patency time were 116 days 116 days (95% confidence interval [CI], 80-150 days) and 116 days (95% CI, 77-155 days), respectively. Three (11%) of the 27 patients presented with stent dysfunction due to tumor ingrowth (n = 1) and intrastent thrombosis (n = 2). Large-bore uncovered metallic stent placement appeared to be a safe and effective method for treating malignant SVC syndrome.

Acute Biliary Obstruction After Gastroduodenal Covered Self-Expanding Metallic Stent Placement in Patients with Previous Biliary Stent Placement for Periampullary Cancer: Frequency and Protective Factors.

We aimed to evaluate the frequency and protective factors of acute biliary obstruction in patients with biliary stent placement followed by gastroduodenal covered self-expandable metallic stent (SEMS) placement owing to progression of periampullary cancer. We retrospectively reviewed 58 patients. Total bilirubin and alkaline phosphatase (ALP) levels before and after gastroduodenal covered SEMS placement were evaluated. The incidence of acute biliary obstruction correlated to age, sex, biliary stent length and type, and longitudinal and axial locations of the lower end of the biliary stent was evaluated. Postprocedural total bilirubin and ALP levels were significantly higher than preprocedural levels (2.30±2.53 vs. 1.53±1.48mg/dL; P=0.008, 331.0±248.8 vs. 258.4±195.2IU/L; P=0.008, respectively). The increase in bilirubin levels was not statistically significant in female patients or patients with a biliary stent length≥6cm or longitudinal location of the lower end of the biliary stent distal to the lower end of the gastroduodenal stent (P>0.05). Seven patients (12.1%) developed acute biliary obstruction. No patients with the lower end of the biliary stent located distal to the lower end of the gastroduodenal stent developed acute biliary obstruction (P=0.012). The incidence of acute biliary obstruction was 12.1% among patients with biliary stent placement followed by gastroduodenal covered SEMS placement. Longitudinal location of the lower end of the biliary stent distal to the lower end of the gastroduodenal stent was a protective factor.

Comparison of Efficacy of Self-Expandable Metallic Stent Placement in the Unresectable Esophageal Cancer Patients.

This is a retrospective study to evaluate the prevention of complications of metallic stent placement in patients with unresectable advanced esophageal cancer. A total of 87 patients were treated with 4 types of metal stents in the esophagus over a period of 18 years. Stent placement was technically successful. The most common prior treatment was chemoradiotherapy. There were no significant differences in the rate of patients with no complications among the prior treatments. Approximately, 30% of patients had the most common chest pain in complications. Stent placement within one month after the completion of chemoradiotherapy should be avoided for the prevention of the chest pain. There was no significant difference in the rate of patients with no complications by lesion location. The rate of no complications was higher for the Niti-S stent than the Gianturco Z-stent or Ultraflex stent. Of note, no complications were noted for the Niti-S ultrathin stent at all. Among cases of stent-related death, the most common type of complication was respiratory disorder caused by the stent that seems to be thick and hard. Therefore, the stent with thin and flexible characteristics like the Niti-S ultrathin stent will solve the various problems of esophageal stent placement.

4:03 PMAbstract No. 404 - Outcomes of overlapping self-expandable metallic stent placement in patients with malignant gastroduodenal obstruction

4:03 PMAbstract No. 404 - Outcomes of overlapping self-expandable metallic stent placement in patients with malignant gastroduodenal obstruction

P-127 Efficacy of Y-Shaped Bilateral Self-Expandable Metallic Stent Placement in Patients with Unresectable Hilar Cholangiocarcinoma

P-127 Efficacy of Y-Shaped Bilateral Self-Expandable Metallic Stent Placement in Patients with Unresectable Hilar Cholangiocarcinoma

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

ObjectiveTo 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 MethodsSixty 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.ResultsA 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).ConclusionUnilateral 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.

Metallic Stent Placement in Patients with Recurrent Malignant Obstruction in the Surgically Altered Stomach

The purpose of this study was to assess the technical feasibility and clinical effectiveness of expandable metallic stent placement in 196 patients with recurrent malignant obstruction in their surgically altered stomach. The 196 patients were treated using five different types of gastric surgery performed for gastric cancer: total gastrectomy (type 1) in 73 patients; distal gastrectomy with gastroduodenostomy (type 2) in 39 patients; distal gastrectomy with a Roux-en-Y gastrojejunostomy (type 3) in 21 patients; distal gastrectomy with a gastrojejunostomy (type 4) in 49 patients; and palliative gastrojejunostomy for unresectable gastric cancer (type 5) in 14 patients. The technical and clinical success rates, complications, dysphagia score, and influence of chemotherapy were evaluated and the complications compared between the two stent types. The overall survival and stent patency were calculated using the Kaplan-Meier method. Stent placement was technically successful in 192 of 196 patients (97.9%), with 184 of the 192 patients (95.8%) showing symptomatic improvement. The mean dysphagia score improved from 3.24±0.64 to 1.48±0.82 (p<0.001). The complication rate was 25%. The incidence of stent migration was significantly higher in fully covered stents and in patients who underwent chemotherapy (p<0.001 and p=0.005, respectively). Chemotherapy was significantly associated with an increase of survival (p<0.001). The median survival and stent patency were 131 and 90days, respectively. Placement of expandable metallic stents in patients with recurrent cancer after a surgically altered stomach is technically feasible and clinically effective. Chemotherapy was associated with increased stent migration and prolonged survival.

MMP-9 Expression after Metallic Stent Placement in Patients with Colorectal Cancer: Association with In-Stent Restenosis

To verify the expression of matrix metalloproteinase (MMP)-9 in stent-induced hyperplastic tissue from patients with colorectal cancer who received colorectal stents as a bridge to surgery. This prospective study was institutional review board-approved, and informed consent was obtained from all patients. Eleven patients (nine men, two women; mean age, 67 years; age range, 53-82 years) with malignant colorectal obstructions who received a colorectal stent between May and December 2010 were included. Tissue specimens were analyzed for MMP-9 and MMP-2 expression. After resection, the tissue was segmented into three parts: tumor tissue, stent-induced tissue hyperplasia, and normal colon tissue. MMP-9 and MMP-2 expression were determined by using zymography, Western blot analysis, and real-time reverse-transcription (qRT) polymerase chain reaction (PCR). Significance of differences between groups was evaluated with Friedman analysis of variance test. Signed-rank test was used to determine differences between malignant tumor tissue and stent-induced hyperplastic tissue groups. Stent placement was technically successful in all 11 patients. Stent-induced hyperplastic tissues were found in all patients. Zymography (P = .003) and Western blot analysis (P = .008) showed that expression of MMP-9 was higher in malignant tumor tissue and stent-induced hyperplastic tissue groups compared with normal colorectal tissue group, demonstrating significant differences between groups but no significant differences between malignant tumor and stent-induced hyperplastic tissues. As for results of qRT PCR analysis, the stent-induced hyperplastic tissue group showed increases in messenger RNA expression level of MMP-9 compared with the malignant tumor tissue group (50.42-fold ± 66.30 higher). High expression of MMP-9 is closely associated with stent-induced colorectal tissue hyperplasia in patients with colorectal cancer.

Percutaneous Metallic Stent Placement in Patients with Cancer Recurrence at Bilioenterostomy Site

PurposeTo investigate the outcomes of percutaneous metallic stent placement in patients with malignant bilioenterostomy obstruction and to assess the risk factors influencing stent patency. Materials and MethodsFrom August 2008 to January 2012, 53 patients with malignant bilioenterostomy obstructions were treated with percutaneous placement of biliary metallic stents; this included expanded polytetrafluoroethylene (ePTFE)–covered stent placement in 36 patients and uncovered stent placement in 17 patients. ResultsA total of 75 stents were successfully placed in 53 patients. No major complications occurred in any patients, and minor complications occurred in nine patients (17%). The mean serum bilirubin level, which was 3.6 mg/dL ± 0.7 before drainage, decreased significantly to 2.5 mg/dL ± 0.4 at 1 month after stent placement (P = .041). Successful internal drainage was achieved in 44 of the 53 patients (83%). Kaplan–Meier analysis showed a median overall survival time of 145 days (95% confidence interval, 100–190 d), a median stent patency time of 313 days (95% confidence interval, 46–580 d), and cumulative stent patency rates at 1, 3, 6, 9, and 12 months of 91%, 75%, 64%, 56%, and 45%, respectively. Multivariate Cox regression analysis showed that the use of uncovered stents (odds ratio, 2.924; P = .033) was the only significant independent factor associated with stent occlusion. ConclusionsPercutaneous metallic stent placement is a safe and effective method for the treatment of patients with malignant bilioenterostomy obstruction. Moreover, as uncovered stent placement is the only significant independent factor associated with stent occlusion, ePTFE-covered stent placement is preferable in these patients.

Placement of a Covered Expandable Metallic Stent to Treat Nonanastomotic Malignant Jejunal Obstructions After Total Gastrectomy With Esophagojejunostomy

The objective of our study was to assess the technical feasibility and clinical effectiveness of expandable metallic stent placement in patients with nonanastomotic malignant jejunal obstruction after total gastrectomy with esophagojejunostomy. We retrospectively analyzed data from 21 patients with malignant jejunal obstruction after total gastrectomy with esophagojejunostomy who received one of two types of expandable metallic stent. Clinical effectiveness was assessed using the following variables: technical and clinical outcomes, complications, dysphagia scores before and after stent placement, patient survival, and stent patency. Complications with related interventions were evaluated and compared between the two stent types. Stent placement was technically successful in 20 of the 21 patients (95%) with 19 of 20 patients (95%) showing symptomatic improvement. Type A stents were used in 10 patients and type B stents in the remaining 10 patients. Complications occurred with seven of 20 stents (35%) and involved stent migration (n = 3), tumor overgrowth (n = 3), or pain (n = 1). The dysphagia score before stent placement (mean ± SD, 3.2 ± 0.5) had improved by 3 days after stent placement (1.3 ± 0.9, p < 0.001) and was maintained compared with the initial score up to 1 month (1.7 ± 1.1, p < 0.001) and 3 months (2.1 ± 1.5, p = 0.021) after stent placement. The median patient survival and stent patency were 114 and 46 days, respectively. The type of stent was not significantly related to complications (p = 0.350). Placement of expandable metallic stents to treat nonanastomotic malignant jejunal obstruction in patients who have undergone total gastrectomy with esophagojejunostomy is feasible and clinically effective.

Percutaneous Biliary Metallic Stent Placement in Patients With Unilobar Portal Vein Occlusion Caused by Advanced Hilar Malignancy: Outcome of Unilateral Versus Bilateral Stenting

The purpose of this study was to investigate the outcome of biliary metallic stent placement in patients with contralateral portal vein occlusion caused by advanced hilar malignancy and to compare the outcomes of unilateral and bilateral stent placement. From January 2007 to December 2009, 41 patients with unilobar portal vein occlusion due to advanced hilar malignancy were enrolled in this retrospective study. All patients were treated with percutaneous placement of biliary metallic stents: unilateral stent placement in 23 patients, bilateral stent placement in 18 patients. There were no significant differences in technical success (p > 0.999), successful drainage (p > 0.999), early cholangitis (p = 0.734), stent occlusion (p = 0.713), stent patency (p = 0.653), or patient survival (p = 0.493) between the two groups. In the patients who underwent unilateral stent placement, a slight decrease in diameter (mean diameter, 7.2 ± 3 mm before drainage, 6.2 ± 3 mm after stent placement) (p = 0.058) was observed in the intrahepatic bile duct of the undrained lobe with portal vein occlusion. Four of the patients who underwent unilateral stent placement had stent malfunctions, but the other 19 patients did not experience cholangitis or jaundice before death or the end of the study. Unilateral biliary metallic stent placement in the lobe with a patent portal vein seems to be a safe and effective palliative treatment of patients with contralateral portal vein occlusion caused by advanced hilar malignancy, obviating bilateral stent placement in these patients.

Food Impaction after Expandable Metal Stent Placement: Experience in 1,360 Patients with Esophageal and Upper Gastrointestinal Tract Obstruction

Purpose To retrospectively evaluate the incidence, predictive factors, and interventional management of food impaction after expandable metallic stent placement in patients with obstruction of the esophagus or upper gastrointestinal tract caused by benign or malignant disease. Materials and Methods Between March 1993 and March 2010, 1,360 patients (1,029 men, 331 women; age range, 21–89 y; mean age, 61 y) underwent fluoroscopically guided stent placement for dysphagia caused by esophageal or gastrointestinal tract strictures. Five types of covered expandable metal stents were used, including four types of esophageal stents (types A–D) and one type of gastroduodenal stent (type E), with types A, B, C, D, and E stents used in 180, 60, 90, 432, and 598 patients, respectively. Multivariate analysis was performed to evaluate factors predictive of food impaction. Results Food impaction occurred in 41 of 1,360 patients (3.0%). The food impaction rates for types A, B, C, D, and E stents were 0.6%, 1.7%, 1.1%, 3.2%, and 4.0%, respectively. Multivariate analysis showed that stent length was an independent predictor of food impaction (odds ratio, 0.839; P = .012). Of the 41 patients with food impaction, 23 underwent endoscopic management, 12 underwent fluoroscopically guided management, and six did not require management because impacted food spontaneously passed through the stent. Conclusions The overall food impaction rate was 3.0%, with multiple logistic regression analysis showing that shorter stent length was the only significant predictor of food impaction. Food impaction can be managed by endoscopic or fluoroscopically guided removal or placement of a second stent.

The Efficacy of the Coaxial Technique Using a 6-Fr Introducer Sheath in Stent Placement for Treating the Obstructions Proximal to the Descending Colon

ObjectiveWe wanted to evaluate the efficacy of stent placement using the coaxial technique with a stiff, long introducer sheath in patients with technical failure using an angiographic catheter for the obstructions proximal to the descending colon.Materials and MethodsSelf-expandable metallic stent placement was attempted under fluoroscopy-guidance in 77 consecutive patients who had malignant colorectal obstruction. Stent placement was performed using an angiographic catheter and a guide wire. If the angiographic catheter could not be advanced over the guide wire into the obstructive lesions proximal to the descending colon, then a 6-Fr introducer sheath was used. The technical success rate, the clinical success rate and the complications were analyzed.ResultsSuccessful stent placement was achieved in 75 of 77 patients (97%). The angiographic catheter failed to advance into the obstructive lesions of 11 patients (M:F = 7:4; mean age, 65.5 years) whose lesions were at the level of the splenic flexure or transverse colon. Therefore, the coaxial technique was implemented in all these 11 patients using a 6-Fr stiff introducer sheath and then the stent placement was successful. There were no complications related to the use of a stiff introducer sheath. Clinical success, which was defined as relief of clinical obstructive bowel symptoms, was obtained within 24 hours in all of patients.ConclusionThe coaxial technique using a stiff introducer sheath can increase the technical success of fluoroscopy-guided, self-expandable metallic stent placement in patients with colonic obstruction proximal to the descending colon.

CT Colonography after Metallic Stent Placement for Acute Malignant Colonic Obstruction

To evaluate the feasibility of using computed tomographic (CT) colonography for preoperative examination of the proximal colon after metallic stent placement in patients with acute colon obstruction caused by colorectal cancer. Institutional review board approval was obtained, and patient informed consent was waived. Fifty patients (mean age +/- standard deviation, 58.5 years +/- 11.7), who demonstrated no postprocedural complication after successful placement of self-expandable metallic stents to treat acute colon obstruction caused by cancer, underwent CT colonography 1-43 days (median, 5 days) after stent placement. CT colonography was performed after cathartic preparation by using magnesium citrate (n = 20) or sodium phosphate (n = 3), combined with oral bisacodyl, or by using polyethylene glycol (n = 27). Fecal/fluid tagging was achieved by using 100 mL of meglumine diatrizoate. The colon was distended by means of pressure-monitored CO(2) insufflation. The sensitivity and specificity of CT colonography in evaluating the colon proximal to the stent and CT colonography-related complications were assessed. The 95% confidence intervals (CIs) were calculated for proportional data. Per-lesion and per-patient sensitivities of CT colonography for lesions 6 mm or larger in diameter in the colon proximal to the stent were 85.7% (12 of 14 lesions; 95% CI: 58.8%, 97.2%) and 90% (nine of 10 patients; 95% CI: 57.4%, 99.9%), respectively. CT colonography depicted all synchronous cancers (two lesions) and advanced adenomas (five lesions). Per-patient specificity for lesions 6 mm and larger in the proximal colon was 85.7% (18 of 21 patients; 95% CI: 64.5%, 95.9%). CT colonography did not generate any false diagnosis of synchronous cancer. False-positive findings at CT colonography did not result in a change in surgical plan for any patients. No CT colonography-associated stent dislodgment/migration or colonic perforation occurred in any patient (95% CI: 0%, 6.2%). CT colonography is a safe and useful method for preoperative examination of the proximal colon after metallic stent placement in patients with acute colon obstruction caused by cancer. (c) RSNA, 2010.

Metallic Stent Placement in Patients with Recurrent Cancer after Gastrojejunostomy

To assess the technical feasibility and clinical effectiveness of placement of expandable metallic stents in patients with recurrent cancer after a gastrojejunostomy. Data from 39 consecutive patients who had undergone metallic stent placement for recurrent malignant obstruction after a gastrojejunostomy were retrospectively analyzed. Thirty patients underwent a distal gastrectomy with a gastrojejunostomy with (n=10) or without (n=20) jejunojejunostomy, two patients underwent distal gastrectomy with a Roux-en-Y gastrojejunostomy, and seven patients underwent a palliative gastrojejunostomy with (n=5) or without (n=2) jejunojejunostomy. A total of 57 metallic stents were used in this study: four bare stents, 29 partially covered stents, and 24 fully covered stents. Types of obstruction were classified into 12 patterns and types of stent placement were classified into 16 patterns. Stent placement was technically successful in all patients. After stent placement, 35 of the 39 patients (90%) experienced improvement of their symptoms, two showed no change, and the remaining two showed aggravation of symptoms as a result of faulty stent placement. Two patients treated with stent placement only in the afferent loop died of aspiration pneumonia. In one of two patients who underwent stent placement according to pattern 6, afferent loop syndrome occurred 10 days after stent placement and was treated by percutaneous pigtail catheter drainage. Stent migration occurred in four of 24 fully covered stents, but in none of the bare or partially covered stents. Tumor ingrowth occurred in one of four bare stents, tumor overgrowth in one of 29 partially covered stents, and mucosal prolapse in one of 24 fully covered stents; all were treated with a second stent placement. Placement of expandable metallic stents in patients with recurrent cancer after a gastrojejunostomy seems to be feasible and effective, but accurate knowledge of the type of surgical procedure performed and determination of the pattern of tumor recurrence are important for successful stent placement.

Cholecystitis After Metallic Stent Placement in Patients With Malignant Distal Biliary Obstruction

Cholecystitis after metallic stent (MS) placement is an issue requiring attention. From our experience, cholecystitis seemed to occur mainly in patients with tumor involvement to the cystic duct orifice. The aim of the present study was to identify risk factors for cholecystitis in patients treated with covered or uncovered MS. We analyzed 246 patients who received MS placement (covered MS in 171 and uncovered in 75) between August 1997 and May 2005 for the treatment of unresectable distal malignant biliary obstruction. Causative diseases were as follows: pancreatic cancer in 162, papillary cancer in 10, bile duct cancer in 41, and metastatic nodes in 33 patients. Tumor involvement to orifice of the cystic duct (OCD) was diagnosed based on cholangiography and intraductal ultrasonography. Cholecystitis after MS placement was found in 13 patients (5.3%). There was no significant difference in the incidence of cholecystitis between covered (5.8%) and uncovered (4.0%) MS. By univariate analysis, tumor involvement of the OCD, MS placed above the papilla, and stricture located at midportion were associated significantly with cholecystitis. By multivariate analysis, only tumor involvement of the OCD was a risk factor, with an odds ratio of 47.206 (95% confidence interval, 5.84-381.60). Cholecystitis after MS placement is associated with tumor involvement to the orifice of the cystic duct, regardless of the type of stent.

Preoperative colonoscopy after self-expandable metallic stent placement in patients with acute neoplastic colon obstruction

In patients with colorectal cancer, a preoperative colonoscopy is recommended to exclude synchronous lesions. Unfortunately, between 7% and 29% of patients with colorectal cancer present with acute colonic obstruction, making complete colonoscopy impossible. The aim of our study was to evaluate the feasibility of a preoperative colonoscopy after effective stent placement in patients with acute neoplastic obstruction. Single-center prospective study. All examinations were carried out at a tertiary referral center with 24-hour emergency endoscopy service. Fifty-seven patients with acute neoplastic colon obstruction. Patients who recovered from an acute colon obstruction by an effective stent placement and who had a resectable cancer underwent a preoperative colonoscopy. Patients with a resectable cancer, complete preoperative colonoscopies, and synchronous lesions rates. Self-expandable metallic stents (SEMS) were placed in 50 of 57 patients (87.8%). Thirty-one of 50 patients had a resectable cancer (62%), and a complete preoperative colonoscopy was possible in 29 of 31 patients (93.4%). A synchronous cancer was detected in 3 patients (9.6%), changing the surgical plan. Seven patients in whom the SEMS placement (12.2%) was unsuccessful underwent an urgent surgical intervention. Nineteen of 50 patients who had stent placement were not eligible for our study because of unresectable cancer. Our study indicates that it is feasible in a majority of patients to perform full preoperative colonoscopy after relief of acute colonic obstruction with SEMS before surgical resection.