Efficacy and safety of metallic stents in patients with unresectable pancreatic cancer receiving gemcitabine

Systemic oncological treatments in patients with advanced pancreatic cancer: a scoping review and evidence map

PURPOSE

To identify, describe, and organise currently available evidence regarding systemic oncological treatments (SOTs) (chemotherapy, targeted/biological therapies, and immunotherapy) compared to best supportive care (BSC) for patients with advanced pancreatic cancer (PC).

METHODS

We conducted a scoping review and evidence mapping, adhering to PRISMA-ScR checklist. We searched MEDLINE, EMBASE, Cochrane Library, Epistemonikos, PROSPERO, and clinicaltrials.gov for eligible studies. We included systematic reviews (SRs), randomised controlled trials (RCTs), quasi-experimental, and observational studies evaluating SOTs compared to BSC or no treatment in patients with advanced PC. Two independent reviewers performed the screening process and data extraction. We developed evidence maps as an interactive visualization display, including the assessed interventions and outcomes.

RESULTS

Of the 50,601 records obtained from our search, we included 43 studies: 2 SRs, 16 RCTs, 4 quasi-experimental studies, 20 observational studies, and 1 protocol for a quasi-experimental study. Forty-two studies reported survival-related outcomes and most favoured SOTs, while five reported toxicity and most favoured BSC. Other patient-centred outcomes, such as quality of life, were scarcely reported.

CONCLUSIONS

This study highlights the current evidence gaps in studies assessing treatments for patients with advanced PC, mainly the lack of reports of non-survival-related outcomes, pointing out research areas that need further attention to make better recommendations for these patients.

Safety and Efficacy of Gemcitabine Plus Nab-Paclitaxel for Metastatic Pancreatic Cancer Patients Undergoing Biliary Stent Placement

BACKGROUND

Gemcitabine plus nab-paclitaxel (GnP) is the first-line chemotherapeutic regimen for metastatic pancreatic cancer (MPC); however, there are concerns regarding its safety in patients undergoing biliary stent placement. This study aimed to examine the tolerability and efficacy of GnP in MPC patients who underwent biliary stent placement.

METHODS

A total of 105 MPC patients who had received GnP treatment between 2015 and 2020 were included and investigated. The patients were divided into two groups: those undergoing biliary stent placement for symptomatic biliary obstruction (BO) (With-BO group) and those without biliary stent placement (Without-BO group). The best tumor response, overall survival (OS), and adverse events in each group were compared.

RESULTS

The partial response, stable disease, and progressive disease rates were 22%, 61%, and 14.6% in the With-BO group, and 26.6%, 46.9%, and 21.9% in the Without-BO group, respectively, with no significant differences. The median OS was 12.2 months and 14.6 months in the With-BO and Without-BO groups, respectively (P = 0.483). Grade 3 or higher biliary tract-related events were significantly more common in the With-BO group (41.5%) than in the Without-BO group (1.6%) (P < 0.001), but all events were managed successfully by urgent intervention. The rates of any treatment-related toxicities, including febrile neutropenia, were not significantly different, and there were no chemotherapy-related deaths in either group.

CONCLUSIONS

GnP can be as tolerable and effective in MPC patients with biliary stents as in those without biliary stents. However, careful management and appropriate reintervention to treat biliary tract-related adverse events are required.

Folfirinox chemotherapy prolongs stent patency in patients with malignant biliary obstruction due to unresectable pancreatic cancer

BACKGROUND

Stent insertion for biliary decompression to relieve jaundice and subsequent biliary infection is necessary for patients with biliary obstruction caused by pancreatic cancer, and it is important to keep the stent patent as long as possible. However, few studies have compared stent patency in terms of chemotherapy in patients with pancreatic cancer. This study aimed to evaluate the differences in stent patency in terms of recently evolving chemotherapy.

METHODS

Between January 2015 and May 2017, 161 patients with pancreatic cancer who had undergone biliary stent insertion with a metal stent were retrospectively analyzed. The relationship between chemotherapy and stent patency was assessed. Additionally, overall survival according to the treatment, risk factors for stent patency, and long-term adverse events were evaluated.

RESULTS

Median stent patency was 42 days for patients with the best supportive care and 217 days for patients with chemotherapy (conventional gemcitabine-based chemotherapy and folfirinox) (P < 0.001). Furthermore, the folfirinox group showed the longest median stent patency and overall survival, with 283 days and 466 days, respectively (P < 0.001) despite higher adverse events rate. Patients who underwent folfirinox chemotherapy after stent insertion had better stent patency in multivariate analysis (HR = 0.26; 95% CI: 0.12-0.60; P = 0.001).

CONCLUSIONS

Compared with patients who received best supportive care only, patients who underwent chemotherapy after stent insertion had better stent patency. More prolonged stent patency can be expected for patients with folfirinox than conventional gemcitabine-based chemotherapy.

International consensus statements for endoscopic management of distal biliary stricture

Distal biliary strictures (DBS) are common and may be caused by both malignant and benign pathologies. While endoscopic procedures play a major role in their management, a comprehensive review of the subject is still lacking. Our consensus statements were formulated by a group of expert Asian pancreatico-biliary interventional endoscopists, following a proposal from the Digestive Endoscopy Society of Taiwan, the Thai Association for Gastrointestinal Endoscopy, and the Tokyo Conference of Asian Pancreato-biliary Interventional Endoscopy. Based on a literature review utilizing Medline, Cochrane library, and Embase databases, a total of 19 consensus statements on DBS were made on diagnosis, endoscopic drainage, benign biliary stricture, malignant biliary stricture, and management of recurrent biliary obstruction and other complications. Our consensus statements provide comprehensive guidance for the endoscopic management of DBS.

Efficacy of a Multiplex Paclitaxel Emission Stent Using a Pluronic® Mixture Membrane versus a Covered Metal Stent in Malignant Biliary Obstruction: A Prospective Randomized Comparative Study

Background/Aims

A drug-eluting stent for unresectable malignant biliary obstruction was developed to increase stent patency by preventing tumor ingrowth. The safety and efficacy of a new generation of metallic stents covered with a paclitaxel-incorporated membrane using a Pluronic^® mixture (MSCPM-II) were compared prospectively with those of covered metal stents (CMSs) in patients with malignant biliary obstructions.

Methods

This study was initially designed as a prospective randomized trial but was closed early because of a high incidence of early occlusion. Therefore, the data were analyzed using the intent-to-treat method. A total of 72 patients with unresectable distal malignant biliary obstructions were prospectively enrolled.

Results

The two groups did not differ significantly in basic characteristics and mean follow-up period (MSCPM-II 194 days vs CMS 277 days, p=0.063). Stent occlusion occurred in 14 patients (35%) who received MSCPM-II and in seven patients (21.9%) who received CMSs. Stent patency and survival time did not significantly differ between the two groups (p=0.355 and p=0.570). The complications were mild and resolved by conservative management in both groups.

Conclusions

There were no significant differences in stent patency or patient survival in MSCPM-II and CMS patients with malignant biliary obstructions.

Stent patency in patients with distal malignant biliary obstruction receiving chemo(radio)therapy

BACKGROUND AND STUDY AIMS

 Recent literature suggests that chemo(radio)therapy might reduce the patency of plastic stents in patients with malignant biliary obstruction. Whether this might also be valid for other types of stents is unknown. The aim of this study was to determine the influence of chemo(radio)therapy on the patency of fully-covered self-expandable metal stents (FCSEMSs) and plastic stents.

PATIENTS AND METHODS

 We retrospectively reviewed the electronic medical records of patients with distal malignant biliary obstruction who underwent biliary stent placement between April 2001 and July 2015. Primary outcome was duration of stent patency. Secondary outcome was stent patency at 3 and 6 months. We used Kaplan-Meier survival analyses to compare stent patency rates between patients who received chemo(radio)therapy and patients who did not.

RESULTS

 A total of 291 biliary stents (151 metal and 140 plastic) were identified. The median cumulative stent patency of FCSEMSs did not differ between patients receiving chemo(radio)therapy (n = 51) and those (n = 100) who did not ( P  = 0.70, log-rank test). The estimated cumulative stent patency of plastic stents was also comparable in 99 patients without and 41 patients with chemo(radio)therapy ( P  = 0.73, log-rank test). At 3 and 6 months, FCSEMS patency rates were 87 % and 83 % in patients without chemo(radio)therapy and 96 % and 83 % in patients with therapy, respectively. Plastic patency rates were 69 % and 55 % in patients without and 85 % and 39 % in patients with therapy, respectively. After 1 year, 78 % of the FCSEMSs were still patent in patients without chemo(radio)therapy and 69 % of the FCSEMSs were still patent in patients with therapy.

CONCLUSION

 Our data indicate that chemo(radio)therapy does not reduce the patency of biliary fully-covered metal and plastic stents.

Endoscopic management of combined malignant biliary and gastric outlet obstruction

Patients with periampullary cancer or gastric cancer often develop malignant biliary obstruction (MBO) and gastric outlet obstruction (GOO), and combined MBO and GOO is not rare in these patients. Combined MBO and GOO is classified by its location and sequence, and treatment strategy can be affected by this classification. Historically, palliative surgery, hepaticojejunostomy and gastrojejunostomy were carried out, but the current standard treatment is combined transpapillary stent and duodenal stent placement. Although a high technical success rate is reported, the procedure can be technically difficult and duodenobiliary reflux with subsequent cholangitis is common after double stenting. Recent development of endoscopic ultrasound (EUS)-guided procedures enables the management of MBO as well as GOO under EUS guidance. EUS-guided biliary drainage is now increasingly reported as an alternative to percutaneous transhepatic biliary drainage in failed endoscopic retrograde cholangiopancreatography (ERCP), and GOO is one of the major reasons for failed ERCP. In addition to EUS-guided biliary drainage, the feasibility of EUS-guided double-balloon-occluded gastrojejunostomy bypass for MBO was recently reported, and EUS-guided double stenting can potentially become the treatment of choice in the future. However, as each procedure has its advantages and disadvantages, treatment strategy should be selected based on the type of obstruction and the prognosis and performance status of the patient.

Photochemical tissue penetration via photosensitizer for effective drug penetration in a non-vascular tumor

To improve the tissue penetration efficiency (PE%) of hydrophilic-drugs in non-vascular drug eluting stents (DES), we designed photochemical tissue penetration (PTP) invested DES (PTP-DES). The PTP technology was applied to the stent as a covering membrane to generate singlet oxygen. Singlet oxygen damages the epithelial layer, so the PE% of released drugs could be improved. To prepare the PTP-DES membrane, chlorin e6 (Ce6, photosensitizer) was incorporated in a gemcitabine (GEM) eluting polyurethane (PU) membrane (Ce6-GEM-PU). Ce6-GEM-PU has smooth surface that is ∼40 μm thick. The photoactivity of Ce6 was maintained for 2 weeks (in vitro GEM releasing period). In a separate cell culture system, both 1.5 folds higher PE% and an improved tumor cell growth inhibition effect were shown after light exposure. Additionally, in tissue penetration experimental system, 2 folds increased in the PE% of GEM was induced by laser exposure at 80 J/cm2. Additionally, improved PE% of hydrophilic molecules (Fluorescein and GEM) was confirmed in colon tumor bearing mice. Consequentially, tumor growth, when implanted with Ce6-GEM-PU, was effectively inhibited without significant side effects. Based on these results, we believe that the PTP-DES system has great potential for improving the therapeutic effect of conventional DES.

Risk factors for covered metallic stent migration in patients with distal malignant biliary obstruction due to pancreatic cancer

BACKGROUND AND AIM

Covered metallic stents (CMSs) were developed to overcome tumor ingrowth in uncovered metallic stents (UMSs) for malignant biliary obstruction, but superiority of CMSs over UMSs is still controversial due to the high migration rate in CMS. Therefore, we conducted this retrospective analysis to clarify risk factors for stent migration, including mechanical properties of CMSs.

METHODS

Patients with unresectable pancreatic cancer, receiving CMS for distal malignant biliary obstruction in five tertiary care centers, were retrospectively studied. Univariate and multivariate analyses to identify prognostic factors for early (< 6 months) stent migration were performed using a proportional hazards model with death or stent occlusion without stent migration as a competing risk. Two mechanical properties were included in the analysis: axial force, the recovery force that leads to a CMS straightening, and radial force (RF), the expansion force against the stricture.

RESULTS

Among 290 patients who received CMS placement for distal malignant biliary obstruction, stent migration rate was 15.2%. CMS migrated early (< 6 months) in 10.0% and distally in 11.7%, respectively. In the multivariate analysis, significant risk factors for early stent migration were chemotherapy (subdistribution hazard ratios [SHR] 4.46, P = 0.01), CMS with low RF (SHR 2.23, P = 0.03), and duodenal invasion (SHR 2.25, P = 0.02).

CONCLUSION

CMS with low RF, chemotherapy, and duodenal invasion were associated with CMS migration from our study.

A novel, fully covered laser-cut nitinol stent with antimigration properties for nonresectable distal malignant biliary obstruction: a multicenter feasibility study

BACKGROUND/AIMS

Stent migration occurs frequently, but the prevention of complications resulting from covered self-expandable metal stents (C-SEMSs) remains unresolved. We prospectively assessed a newly developed C-SEMS, a modified covered Zeo stent (m-CZS), in terms of its antimigration effect.

METHODS

Between February 2010 and January 2011, an m-CZS was inserted into 42 patients (31 initial drainage cases and 11 reintervention cases) at a tertiary referral center and three affiliated hospitals. The laser-cut stent was flared for 1.5 cm at both ends, with a 1 cm raised bank located 1 cm in from each flared end. The main outcome of this study was the rate of stent migration, and secondary outcomes were the rate of recurrent biliary obstruction (RBO), the time to RBO, the frequencies of complications, and overall survival.

RESULTS

Of the 31 patients with initial drainage, stent migration occurred in four (12.9%, 95% confidence interval, 5.1% to 29.0%), with a mean time of 131 days. RBO occurred in 18 (58%), with a median time to RBO of 107 days. Following previous C-SEMS migration, seven of 10 patients (70%) did not experience m-CZS migration until death.

CONCLUSIONS

m-CZSs with antimigration properties effectively, although not completely, prevented stent migration after stent insertion.

Impact of anticancer treatment on recurrent obstruction in covered metallic stents for malignant biliary obstruction

BACKGROUND

In patients with unresectable malignant biliary obstruction (MBO), anticancer treatment is often administered. The impact of anticancer treatment on recurrent biliary obstruction in covered self-expandable metallic stents (SEMS) has not been fully elucidated.

METHODS

Data on 279 patients enrolled in a multicenter prospective cohort study of two different covered SEMS for distal MBO, WATCH study (141 partially covered WallFlex stents and 138 partially covered Wallstents) were retrospectively analyzed. The rates and causes of recurrent biliary obstruction (stent occlusion or migration) were compared between anticancer treatment group (n = 173) and best supportive care alone (BSC) group (n = 106). Cumulative time and prognostic factors for recurrent biliary obstruction were analyzed, using a proportional hazards model with death without recurrent biliary obstruction as a competing risk.

RESULTS

The overall rate (43 vs. 25%, P = 0.002) and the cumulative incidence (16.1 vs. 8.2, 27.9 vs. 18.9 and 44.1 vs. 26.6% at 3, 6 and 12 months, P = 0.030 by Gray's test) of recurrent biliary obstruction were significantly higher in anticancer treatment group compared with BSC group. The multivariate analysis revealed anticancer treatment [subdistribution hazard ratio (SHR) 1.93, P = 0.007) as well as the use of a partially covered WallFlex stent (SHR 0.65, P = 0.049) as prognostic factors.

CONCLUSIONS

Anticancer treatment was a risk factor for recurrent biliary obstruction in covered SEMS for distal MBO. The superiority of a partially covered WallFlex stent was again confirmed in this competing risk analysis; UMIN-CTR: UMIN000002293.

Efficacy of a metallic stent covered with a paclitaxel-incorporated membrane versus a covered metal stent for malignant biliary obstruction: a prospective comparative study

BACKGROUND

The placement of a self-expandable metallic stent (SEMS) is a widely used nonsurgical treatment method in patients with unresectable malignant biliary obstructions but SEMS is susceptible to occlusion by tumor ingrowth or overgrowth.

AIM

The efficacy and safety of a metallic stent covered with a paclitaxel-incorporated membrane (MSCPM) in which paclitaxel provided an antitumoral effect was compared prospectively with those of a covered metal stent (CMS) in patients with malignant biliary obstructions.

METHODS

Patients with unresectable distal malignant biliary obstructions (n = 106) were prospectively enrolled in this study at multiple treatment centers. A MSCPM was inserted endoscopically in 60 patients, and a CMS was inserted in 46 patients. Patients underwent systemic chemotherapy regimens alternatively according to disease characteristics.

RESULTS

The two groups did not differ significantly in mean age, male to female ratio, or mean follow-up period. Stent occlusion due to tumor ingrowth occurred in 12 patients who received MSCPMs and in eight patients who received CMSs. Stent patency and survival time did not differ significantly between the two groups (p = 0.116, 0.981). Chemotherapy had no influence on stent patency, but gemcitabine-based chemotherapy was a significant prognostic factor for survival time (p = 0.012). Complications, including cholangitis and pancreatitis, were found to be acceptable in both groups.

CONCLUSIONS

Although the use of a MSCPM produced no significant differences in stent patency or patient survival in patients with malignant biliary obstructions compared with the use of a CMS, this study demonstrated that MSCPM can be used safely in humans.

Stent patency using competing risk model in unresectable pancreatic cancers inserted with biliary self-expandable metallic stent

BACKGROUND AND AIM

Biliary self-expandable metallic stents (SEMS) play an important role in the quality of life and palliative treatment in unresectable pancreatic cancer patients. We aimed to determine the factors affecting the patency of biliary SEMS and the survival in unresectable pancreatic cancer with obstructive jaundice.

METHODS

Considering the competing risk and survival, we retrospectively evaluated the patency in 107 unresectable pancreatic cancer patients with obstructive jaundice who were successfully treated with biliary SEMS from January 2000 to April 2010.

RESULTS

There were 107 incidents of biliary drainage that were clinically successful and the overall survival period was a median of 133 days. Stent occlusion before death was observed in 36 (33.6%) of 107 patients. Cumulative stent obstruction rates were 4.7%, 16.8%, and 24.4% at 1, 3, and 6 months, respectively. Lower cancer stage (<5 month's hazard ratio [HR] = 2.327, >5 month's HR = 0.108) was only associated with the longer patency of the stents in a multivariable analysis using a Fine and Gray model that considered competing risk. In multivariable analysis, lower cancer stage, uncovered stent and normalized serum bilirubin level were associated with a longer survival period (HR = 2.335, 1.906 and 1.795 respectively, P < 0.05).

CONCLUSION

The patency of biliary SEMS in unresectable pancreatic cancers might be affected by the stage. Lower cancer stage and normalized bilirubin are associated with longer survival.

Self-expanding metal stents (SEMS) provide superior outcomes compared to plastic stents for pancreatic cancer patients undergoing neoadjuvant therapy

BACKGROUND

Neoadjuvant therapy is increasingly utilized for pancreatic cancer patients to decrease tumor burden in anticipation of later surgical resection. However, infectious complications such as life threatening cholangitis may occur for those with biliary obstruction. We hypothesized that placement of metal rather than plastic stents in such patients results in lower rates of stent-related complications, leading to improved clinical outcomes.

METHODS

Retrospective cohort of pancreatic cancer patients treated by the University of Michigan Multidisciplinary Pancreatic Cancer Destination Program between January 2005 and June 2010. Only patients undergoing neoadjuvant therapy with one or more biliary stents placed for malignant obstruction were studied. Time to stent complication was compared between metal and plastic stents. The complication rate was estimated as the ratio of complications to total stent exposure time and 95% confidence intervals were calculated.

RESULTS

52 patients met inclusion criteria. A total of 113 stents were placed in 52 patients (70 plastic, 43 metal). The complication rate was almost 7 times higher with plastic stents, 0.20 (95% CI, 0.14-0.30), than with metal stents, 0.03 (95% CI, 0.01-0.06). Moreover, the rate of hospitalization for stent-related complications was 3-fold higher in the plastic stent group than the metal stent group. The first quartile estimate of time to stent complication was almost 5 times longer for metal than for plastic stents (44 vs. 200 days) (P<0.0001).

CONCLUSION

Compelling evidence indicates that self-expanding metal, not plastic stents should be used for malignant biliary obstruction in patients undergoing neoadjuvant therapy for pancreatic cancer.

Long-term risk of cholangitis in patients with metal stents for malignant biliary obstruction

BACKGROUND

Patients with malignant biliary obstruction are commonly living longer than previously due to improved oncologic therapies, often exceeding expected times of self-expanding metal stent patency.

AIMS

The purpose of this study was to assess the long-term risk and impact of cholangitis in these patients.

METHODS

Retrospective review of electronic medical records at an academic medical center.

RESULTS

One hundred and one patients had a self-expanding metal stent placed for malignant biliary obstruction. The median survival after SEMS was 214 days. Of these patients, 22 % developed at least one episode of cholangitis requiring inpatient admission, 20 % (9/45) of patients were hospitalized for cholangitis at 6 months, 40 % (8/20) at 1 year, and 75 % (3/4) at 2 years. All of the (8/8) patients receiving chemotherapy prior to hospitalization for cholangitis experienced delays in subsequent chemotherapy. Follow-up of 36 episodes of cholangitis revealed a 14 % 30-day mortality.

CONCLUSIONS

Cholangitis develops commonly in long-term survivors with self-expanding metal stents for malignant biliary obstruction, and is associated with delays in chemotherapy and a 14 % 30-day mortality.

Endoscopic retrograde cholangiopancreatography for distal malignant biliary stricture

Endoscopic biliary stent placement is widely accepted as palliation for malignant biliary obstruction or as a treatment of benign biliary stricture. Although various biliary stent designs have become available since self-expandable metallic stents were introduced, no single ideal stent has been developed. An ideal stent should be patent until death, or surgery, in patients with resectable malignant biliary obstruction. Fewer complications, maneuverability, cost-effectiveness, and removability are also important factors. Alternatively, should we develop a novel method for biliary drainage other than biliary stenting via endoscopic retrograde cholangiopancreatography? This article reviews the current status of biliary stenting for malignant biliary obstructions.

Repeat Procedures Within 30 days in Patients Stented for Malignant Distal Biliary Strictures: Experience of 508 Patients at a Tertiary Referral Center

Background

Stent related occlusion and migration remains a problem despite attempts to improve stent design over this time period. Flanged polyethylene plastic stents (FPS) remains the stent of choice in most centers. Early failure of stents placed for malignant extrahepatic biliary strictures (MEBS) has not previously been studied in detail. We set out to determine the incidence and reasons for biliary stent change within 30 days of the index procedure in a large tertiary center population during a period where (FPS) was the sole plastic stent used.

Methods

Retrospective analysis of endoscopic retrograde cholangiography (ERCP) was undertaken in patients who were stented for presumed or known MEBS between 1993 and 2001. Patients who required repeat stenting within 30 days were identified.

Results

All 508 patients were stented for MEBS. 5.7% of patients had a total of 34 repeat stenting procedures within 30 days of the index procedure; 27of 29 index stents were plastic, 2 were self-expandable metal stents (SEMS), 20 (3.9%) patients had stent failure as the reason for a stent exchange (plastic stent occlusion n = 15, mean time to stent change 14 ± 8.3 days; metal stent occlusion n = 2, mean time to stent change 24.5 ± 7.8 days; plastic stent migration n = 3, mean time to stent change 25 ± 5.3 days). There was a statistically significant difference in the time to stent change between the occluded plastic stent and migrated plastic stent cases (P = 0.045, 95% CI -21.7 to -0.29). 6 patients spent at least 2 additional days in hospital as a result of stent failure.

Conclusions

Early stent failure is an uncommon problem, especially in patients with SEMS. Early plastic stent failure appears to occur sooner with stent occlusion than with stent migration. Early stent failure is associated with significant morbidity and bears an economic impact in additional procedures and hospital stay.

Duodenal invasion is a risk factor for the early dysfunction of biliary metal stents in unresectable pancreatic cancer

BACKGROUND

Although the placement of self-expandable metal stents (SEMSs) has been widely accepted as palliation for distal malignant biliary obstruction, the risk factors for their early dysfunction remain unclear.

OBJECTIVE

To identify risk factors for early (<3 months) SEMS dysfunction in unresectable pancreatic cancer.

DESIGN

A multicenter retrospective study.

SETTING

Five tertiary referral centers.

PATIENTS

Patients were included who underwent first-time SEMS placement for distal malignant biliary obstruction caused by pancreatic cancer between April 1994 and August 2010.

MAIN OUTCOME MEASUREMENTS

Rates and causes of early dysfunction were evaluated, and risk factors were analyzed.

RESULTS

In all, 317 eligible patients were identified. Covered SEMSs were placed in 82% of patients. Duodenal invasion was observed endoscopically in 37%. The median time to dysfunction was 170 days. The rates of all and early SEMS dysfunction were 55% and 31%, respectively. The major causes of SEMS dysfunction were food impaction and nonocclusion cholangitis (21% each) in early dysfunction and sludge (29%) in nonearly dysfunction. The rate of early dysfunction was 42% with duodenal invasion and 24% without duodenal invasion (P = .001). Early dysfunction caused by food impaction was more frequent in patients with duodenal invasion (10% and 4%, P = .053). Duodenal invasion was a risk factor (odds ratio 2.35; 95% CI, 1.43-3.90; P = .001) in a multiple logistic regression model.

LIMITATIONS

A retrospective design.

CONCLUSIONS

Duodenal invasion is a risk factor for early SEMS dysfunction in patients with pancreatic cancer.

Advances in diagnosis, treatment and palliation of pancreatic carcinoma: 1990-2010

Several advances in genetics, diagnosis and palliation of pancreatic cancer (PC) have occurred in the last decades. A multidisciplinary approach to this disease is therefore recommended. PC is relatively common as it is the fourth leading cause of cancer related mortality. Most patients present with obstructive jaundice, epigastric or back pain, weight loss and anorexia. Despite improvements in diagnostic modalities, the majority of cases are still detected in advanced stages. The only curative treatment for PC remains surgical resection. No more than 20% of patients are candidates for surgery at the time of diagnosis and survival remains quite poor as adjuvant therapies are not very effective. A small percentage of patients with borderline non-resectable PC might benefit from neo-adjuvant chemoradiation therapy enabling them to undergo resection; however, randomized controlled studies are needed to prove the benefits of this strategy. Patients with unresectable PC benefit from palliative interventions such as biliary decompression and celiac plexus block. Further clinical trials to evaluate new chemo and radiation protocols as well as identification of genetic markers for PC are needed to improve the overall survival of patients affected by PC, as the current overall 5-year survival rate of patients affected by PC is still less than 5%. The aim of this article is to review the most recent high quality literature on this topic.

New method of covered wallstents for distal malignant biliary obstruction to reduce early stent-related complications based on characteristics

AIM

We previously reported a low occlusion rate with covered Wallstents for malignant biliary obstruction, but stent-related complications other than occlusion posed a problem. A modified covered Wallstent insertion method based on stent characteristics was evaluated to reduce stent-related complications.

METHODS

A total of 138 patients with distal malignant biliary obstruction received covered Wallstent placement. From October 2001 to October 2003, 69 patients received covered Wallstent placement (Group 1). Thereafter, we modified our stent insertion method and 69 patients received stent placement using this modified method from November 2003 to January 2007 (Group 2). The modified insertion method consists of endoscopic sphincterotomy carried out in patients without pancreatic duct invasion and longer stent placement with the center of the stent located in the center of the biliary stricture to prevent pancreatitis, kinking of the bile duct, and stent dislocation. A comparative analysis was carried out using prospectively collected data in these two cohorts.

RESULTS

Tumor ingrowth was not observed, and stent occlusion rate was 18.8% in Group 1 and 23.2% in Group 2. The overall rates of stent-related complications did not differ (39.1% in Group 1 and 30.4% in Group 2), but stent-related complications within 3months decreased from 22 episodes in Group 1 to 13 episodes in Group 2. Median event-free survival was prolonged by modified stent insertion method (125days in Group 1 and 268days in Group 2, P=0.020), although cumulative survival and stent patency were not significantly different.

CONCLUSIONS

Our modified method of covered Wallstent placement showed improved event-free survival.