Treatment of malignant esophageal obstruction with silicone-coated metallic self-expanding stents.

Six patients with high-grade malignant esophageal obstruction were treated with silicone-coated metallic self-expanding esophageal stents (Z stents). Endoscopic placement of stents was well tolerated. All patients achieved excellent palliation, defined by a decrease of at least two dysphagia grades, which was sustained. Complications occurred during follow-up in four patients and included stent migration, silicone disruption with tumor ingrowth, food impaction, and perforation (discovered at autopsy) at the distal stent site. Three of the four complications were promptly treated by endoscopic or radiologic intervention. Recent modification in stent design and placement technique will hopefully reduce complications. The self-expanding stent has several theoretical advantages over the rigid plastic stent and Nd:YAG laser for palliation of obstructing esophageal malignancy.     

内镜下覆膜食管支架治疗食管癌性狭窄及食管气管瘘的临床应用价值

目的探讨内镜下覆膜食管支架治疗食管癌性狭窄及食管气管瘘的临床价值及食管支架置入术并发症的防治。方法回顾性分析163例晚期食管癌患者内镜下覆膜食管支架治疗食管癌性狭窄及食管气管瘘的临床资料,其中7例患者为食管癌性狭窄并食管-支气管瘘伴双下肺感染,19例患者为食管癌术后复发吻合口狭窄置入镍钛记忆合金覆膜支架。102例患者由于食管过于狭窄先行食管扩张,再进行内镜下放置食管支架,35例患者直接内镜下置入食管支架。结果 163例患者先后放置174个支架,均一次性置入成功,成功率为100%。163例患者均有不同程度胸痛不适,有32例支架再狭窄,其中19例单纯行支架内球囊扩张,11例于原支架上端内部分重叠再放置一支架,有26例行氩气刀再通治疗。7例患者出现支架移位,有2例支架进入食管瘘管内于次日在内镜下取出支架重新放置。所有病例均未出现食管破裂、食管血肿或出血等严重并发症,术后患者进食能力提高,食管气管瘘闭合。结论内镜下覆膜食管支架置入术是中晚期食管癌性狭窄简单、安全、有效的姑息治疗方法,能提高患者的生活质量,延长患者的生存期。     

The future of esophageal endoprosthetics including the use of biodegradable materials

Endoscopic esophageal stent placement is an effective palliative treatment for malignant dysphagia and complications related to esophageal malignancies. Lately, esophageal stents have also been successfully used for benign indications including anastomotic stricture, iatrogenic perforation or leak, achalasia, fistula and to stabilize patients with esophageal variceal bleeding. At present, there are a wide variety of esophageal stents available to choose from; however, an ideal esophageal stent, which is both effective and without complications, has yet to be developed. Despite the evolution in this field, challenges such as stent migration, malignant tissue ingrowth, and recurrent stricture are some of the unsolved problems. In this article, we discuss about currently available esophageal stents including biodegradable stents, various stent materials, stent designs, indications for esophageal stent placement in treating both benign and malignant esophageal diseases, clinical outcomes, complications, novel esophageal stents including drug fiber coated stents, dynamic esophageal stents, and the future direction of esophageal endoprosthetics.     

Nonmalignant obstruction is a common problem with metal stents in the treatment of esophageal cancer

BACKGROUND: The use of metal stents for the treatment of dysphagia due to esophageal malignancy is an important advance because of ease of delivery and their self-expandable property. Obstruction due to tumor overgrowth is a recognized complication, but nonmalignant obstruction in patients with metal stents is rarely reported. METHODS: Database records of patients who had esophageal cancer and underwent metal stent insertion were reviewed. RESULTS: A total of 116 patients were seen between October 1993 and October 1997. Four types of metal stents had been used (Ultraflex, Z Stent, Wallstent, and Esophacoil). Detailed follow-up information was available for 81 patients, who constitute the study sample. Forty-nine (60%) stent obstructions were reported, 26 of the 49 (53%) were due to tumor overgrowth and 23 (47%) were not associated with malignancy. Histologic analysis of the nonmalignant obstructing tissue showed granulation tissue (56%), reactive hyperplasia (22%) and fibrosis (22%). CONCLUSIONS: Nonmalignant obstruction is a common although infrequently reported complication after placement of metal stents for esophageal cancer. The tissue response of the esophageal mucosa occurred with all 4 types of stents used. No specific characteristic of the stent or prior treatment seems to be related to obstruction of the stent in patients with either nonmalignant obstruction or tumor overgrowth.     

Esophageal stent placement without fluoroscopy

BACKGROUND: Access to fluoroscopic equipment is limited in some regions where esophageal cancer is common. This report describes a simple method for placement of expandable esophageal stents without fluoroscopy. METHODS: Patients with dysphagia due to unresectable esophageal cancer underwent esophageal stent placement under endoscopic control alone. A colored mark on the stent delivery catheter was used to properly position the undeployed stent with respect to the proximal end of the tumor. RESULTS: Stent placement was attempted in 70 patients and was successful in every case. There were no immediate complications of stent placement. Mean dysphagia score decreased from 3.3 before stent placement to 0.5 at follow-up. There was a trend toward lower dysphagia scores in patients who received coated stents. CONCLUSION: Expandable esophageal stents can be accurately and safely placed under direct endoscopic control, without fluoroscopy.     

Biliary stents in malignant obstructive jaundice due to pancreatic carcinoma: a cost-effectiveness analysis

OBJECTIVES: Obstructive jaundice frequently complicates pancreatic carcinoma and is associated with complications such as malabsorption, coagulopathy, progressive hepatocellular dysfunction, and cholangitis in addition to disabling pruritus, which greatly interferes with terminal patients' quality of life. Endoscopic placement of biliary stents decreases the risk of these complications and is considered the procedure of choice for palliation for patients with unresectable tumors. We used decision analysis with Markov modeling to compare the cost-effectivenesses of plastic stents and metal stents in patients with unresectable pancreatic carcinoma. METHODS: A model of the natural history of unresectable pancreatic carcinoma was constructed using probabilities derived from the literature. Cost estimates were obtained from Medicare reimbursement rates and supplemented by the literature. Two strategies were evaluated: 1) initial endoscopic plastic stent placement and 2) initial endoscopic metal stent placement. We compared total costs and performed cost-effectiveness analysis in these strategies. The outcome measures were quality-adjusted life months. Sensitivity analyses were performed on selected variables. RESULTS: Our baseline analysis showed that initial plastic stent placement was associated with a total cost of $13,879/patient and 1.799 quality-adjusted life months. Initial placement of a metal stent cost $13,466/patient and conferred 1.832 quality-adjusted life months. Among the variables examined, expected patient survival was demonstrated by sensitivity analyses to have the most influence on the results of the model. CONCLUSION: Initial endoscopic placement of a metal stent is a cost-saving strategy compared to initial plastic stent placement, particularly in patients expected to survive longer than 6 months.     

Morbidity and mortality after self-expandable metallic stent placement in patients with progressive or recurrent esophageal cancer after chemoradiotherapy

BACKGROUND: Placemet of self-expandable metallic stents in patients with advance esophageal cancer improves dysphagia and occludes tracheoesophageal fistulas. However, the safety of self-expandable metallic stents for patients who have undergone chemoradiotherapy is controversial. This study evaluated the morbidity and modality after self-expandable metallic stent placement in patients with progressive or recurrent esophageal cancer after chemoradiotherapy. METHODS: A total of 22 patients in whom self-expandable metallic stents were placed because of progressive or recurrent esophageal cancer after chemoradiotherapy were studied. RESULTS: All 22 patients had dysphagia, and 13 had a tracheoesophageal fistula. After self-expandable metallic stent placement, the mean dysphagia grade improved from 3.5 to 0.9, and tracheoesophageal fistula was successfully managed in all cases. Seventeen patients had T4 stage disease, and among 8 of them with invasion to the aorta, 6 (75%) died of sudden massive hemorrhage. Median survival for these 6 patients was 31 days (range 13-63 days) compared with 67 days (range 4-262 days) for all patients after self-expandable metallic stent placement. CONCLUSION: Self-expandable metallic stent placement improved dysphagia and was useful for treatment of tracheoesophageal fistula. However, for patients with T4 lesions that invade to the aorta, self-expandable metallic stent placement after chemoradiotherapy should be considered carefully.     

New design esophageal stents for the palliation of dysphagia from esophageal or gastric cardia cancer: a randomized trial

BACKGROUND & AIM: Stents are often used for the palliation of inoperable esophageal or gastric cardia cancer. One of the drawbacks of the currently used stents is the high percentage of recurrent dysphagia due to stent migration and tissue growth. New stents have been designed to overcome this unwanted sequela of stent placement. In the present study, we investigated whether results of stent placement could be improved with newer stent designs. METHODS: Between June 2004 and May 2006, 125 patients with dysphagia from inoperable carcinoma of the esophagus or gastric cardia were randomized to placement of an Ultraflex stent (N = 42), Polyflex stent (N = 41), or Niti-S stent (N = 42). Patients were followed by scheduled telephone calls at 14 days after treatment, and then monthly for 6 months or until death. Technical and functional outcome, complications, recurrent dysphagia, and survival were analyzed with, chi(2) tests, Kaplan-Meier curves, and log-rank tests. RESULTS: Stent placement was technically successful in all patients with an Ultraflex stent, in 34/41 (83%) patients with a Polyflex stent, and in 40/42 (95%) patients treated with a Niti-S stent (P= 0.008). Dysphagia score improved from a median of 3 (liquids only) to 1 (ability to eat some solid food) in all patients. There were no differences in complications among the three stent types. Recurrent dysphagia, caused by tissue in- or overgrowth, migration, or food obstruction, was significantly different between patients with an Ultraflex stent and patients with a Polyflex stent or Niti-S stent (22 [52%]vs 15 [37%]vs 13 [31%], P= 0.03). Stent migration occurred more frequently with Polyflex stents, whereas tissue in- or overgrowth was more frequently seen with Ultraflex stents, and to a lesser degree, Niti-S stents. No differences were found in survival (median survival: Ultraflex stent 132 days vs Polyflex stent 102 days vs Niti-S stent 159 days) among the three stent types. CONCLUSIONS: All three stents are safe and offer adequate palliation of dysphagia from esophageal or gastric cardia cancer. Nonetheless, Polyflex stents seem the least preferable in this patient group, as placement of this device is technically demanding and associated with a high rate of stent migrations.     

Self-expandable metallic stents for palliation of patients with malignant gastric outlet obstruction caused by stomach cancer

AIM: To ascertain clinical outcome and complications of self-expandable metal stents for endoscopic palliation of patients with malignant obstruction of the gastrointestinal (GI) tract. METHODS: A retrospective review was performed throughout August 2000 to June 2005 of 53 patients with gastric outlet obstruction caused by stomach cancer. All patients had symptomatic obstruction including nausea, vomiting, and decreased oral intake. All received self-expandable metallic stents. RESULTS: Stent implantation was successful in all 53 (100%) patients. Relief of obstructive symptoms was achieved in 43 (81.1%) patients. No immediate stent-related complications were noted. Seventeen patients had recurrent obstruction (tumor ingrowth in 14 patients, tumor overgrowth in 1 patient, and partial distal stent migration in 2 patients). The mean survival was 145 d. Median stent patency time was 187 d. CONCLUSION: Endoscopic placement of self-expandable metallic stents is a safe and effective treatment for the palliation of patients with inoperable malignant gastric outlet obstruction caused by stomach cancer.     

Placement of PEG tubes through previously placed self-expanding esophageal metal stents

BACKGROUND: Self-expanding metal stents are frequently used to palliate patients with malignant dysphagia and close tracheoesophageal fistulae. Despite proper stent positioning and deployment, in a subset of patients there is no improvement in dysphagia, closure of tracheoesophageal fistulae, or resolution of anorexia. Such patients may require a PEG tube. It has been suggested that PEG placement through a preexisting esophageal stent is problematic because of the risks of gastrostomy tube impaction within the stent and resultant stent migration. METHODS: Case records were retrospectively reviewed of 9 consecutive patients with indwelling esophageal self-expanding metal stents undergoing attempted PEG. OBSERVATIONS: PEG tube placement was successful in all patients. In 1 patient, the stent migrated distally into the stomach during PEG placement. This was managed endoscopically without further complication. CONCLUSIONS: PEG placement in patients with previously placed esophageal self-expanding metal stents is a relatively safe and feasible procedure, although stent migration may occur.     

Usefulness of biodegradable stents constructed of poly-l-lactic acid monofilaments in patients with benign esophageal stenosis

AIM： To report 13 patients with benign esophagea stenosis treated with the biodegradable stent.
METHODS： We developed a Ultraflex-type stent by knitting poly-/-lactic acid rnonofilaments.
RESULTS： Two cases were esophageal stenosis caused by drinking of caustic liquid, 4 cases were due to surgical resection of esophageal cancers, and 7 cases were patients with esophageal cancer who received the preventive placement of biodegradable stents for postendoscopic mucosal dissection （ESD） stenosis. The preventive placement was performed within 2 to 3 d after ESD. In 10 of the 13 cases, spontaneous migration of the stents occurred between 10 to 21 d after placement. In these cases, the migrated stents were excreted with the feces, and no obstructive complications were experienced. In 3 cases, the stents remained at the proper location on d 21 after placement. No symptoms of re-stenosis were observed within the follow-up period of 7 mo to 2 years. Further treatment with balloon dilatation or replacement of the biodegradable stent was not required.
CONCLUSION： Biodegradable stents were useful for the treatment of benign esophageal stenosis, particularly for the prevention of post-ESD stenosis.     

Usefulness of biodegradable stents constructed of poly-l-lactic acid monofilaments in patients with benign esophageal stenosis

AIM: To report 13 patients with benign esophageal stenosis treated with the biodegradable stent. METHODS: We developed a Ultraflex-type stent by knitting poly-l-lactic acid monofilaments. RESULTS: Two cases were esophageal stenosis caused by drinking of caustic liquid, 4 cases were due to surgical resection of esophageal cancers, and 7 cases were patients with esophageal cancer who received the preventive placement of biodegradable stents for post- endoscopic mucosal dissection (ESD) stenosis. The preventive placement was performed within 2 to 3 d after ESD. In 10 of the 13 cases, spontaneous migration of the stents occurred between 10 to 21 d after placement. In these cases, the migrated stents were excreted with the feces, and no obstructive complications were experienced. In 3 cases, the stents remained at the proper location on d 21 after placement. No symptoms of re-stenosis were observed within the follow-up period of 7 mo to 2 years. Further treatment with balloon dilatation or replacement of the biodegradable stent was not required. CONCLUSION: Biodegradable stents were useful for the treatment of benign esophageal stenosis, particularly for the prevention of post-ESD stenosis.     

Newly developed biodegradable stents for benign gastrointestinal tract stenoses: a preliminary clinical trial

We developed an Ultraflex-type stent by knitting polylactic acid monofilaments. The purpose of this study was to evaluate the stent's clinical usefulness for treating benign stenoses in the gastrointestinal tract. The radial force of the biodegradable stent was compared with those of commercially available metallic stents. The measured radial force of the new biodegradable stent was higher than that of commercially available metallic stents. The biodegradable stents were applied in 2 patients with benign gastrointestinal stenoses. The first patient was a 19-year-old female with esophageal stenosis, due to drinking of caustic potash in an attempt to commit suicide. The second patient was a 75-year-old male who had a stenosis at the anastomotic site after esophageal cancer resection. In both cases, the placement of the stent was performed successfully, and the patients' complaints improved immediately after stent placement. There were no complications during stent placement. The stenosis had not recurred at the six-month follow-up examination. In conclusion, the newly developed biodegradable stents were useful in treating benign stenoses of the alimentary tract.     

Palliative esophageal stent placement using endoscopic guidance without fluoroscopy

AIMS: Fluoroscopy is not available in every endoscopic unit. This situation leads to delays in treatment or to transfer of patients to other centres for stent insertion. We assessed safety and effectiveness of expandable esophageal metal stent placement under endoscopic control without fluoroscopy using a thin gastroscope. PATIENTS AND METHODS: From October 2002 to June 2004, thirty-three consecutive patients have been included for esophageal stent placement under endoscopic control alone with a nasogastroscope (5.9 mm). A proximal release covered stent (Ultraflex; Boston Scientific Microvasive) was used. Indications were malignant esophageal stricture (N = 26), malignant extrinsic compression (N = 2 ) and esophago-respiratory neoplastic fistulae (N = 5). RESULTS: Stent placement using endoscopic control alone was successful in 30/33 (90%) patients. Complications occurred in 11 patients. Early complications (<7 days) included one death from pulmonary embolism, severe retrosternal pain needing transient morphinic treatment (N = 2) and GERD despite antisecretory therapy (N = 1). Late complications included: food impaction (N = 1), tumour overgrowth-related obstruction of the stent (N = 5) and one late esophago-respiratory fistula at 4 months at the proximal end of the stent. Relief of dysphagia was obtained for all patients at 48 hours and dysphagia score decreased from 3.1 before stent to 1.2 at 1 month (P < 0.05). CONCLUSION: Expandable esophageal stents can be accurately and safely placed using endoscopy with a thin gastrosocope. This method obviates the requirement of fluoroscopic access, lacking in many centres, and avoids exposure to X-ray.     

Esophageal stent fracture:case report and review of the literature

Endoscopic esophageal stent placement is widely used in the treatment of a variety of benign and malignant esophageal conditions.Self expanding metal stents(SEMS)are associated with significantly reduced stent related mortality and morbidity compared to plastic stents for treatment of esophageal conditions;however they have known complications of stent migration,stent occlusion,tumor ingrowth,stricture formation,reflux,bleeding and perforation amongst others.A rare and infrequently reported complication of SEMS is stent fracture and subsequent migration of the broken pieces.There have only been a handful of published case reports describing this problem.In this report we describe a case of a spontaneously fractured nitinol esophageal SEMS,and review the available literature on the unusual occurrence of SEMS fracture placed for benign or malignant obstruction in the esophagus.SEMS fracture could be a potentially dangerous event and should be considered in a patient having recurrent dysphagia despite successful placement of an esopha-geal SEMS.It usually requires endoscopic therapy and may unfortunately require surgery for retrieval of a distally migrated fragment.Early recognition and prompt management may be able to prevent further problems.     

Distally migrated esophageal self-expanding metal stents: wait and see or remove?

BACKGROUND: Extraction of a migrated esophageal stent may be extremely difficult with a substantial risk of complications including esophageal perforation and hemorrhage. METHODS: Retrospectively 242 patients were evaluated who underwent implantation of self-expanding metal stents (SEMS) and 13 (5.4%) were identified with distal stent migration. In all cases of stent dislocation into the stomach, extraction of the stent was not attempted and a new stent was inserted. RESULTS: Twelve patients had dysphagia. One patient underwent surgery because of stent impaction in the colon, 3 had unrecognized passage of the stent per rectum, and 9 had evidence of the stent into the stomach. Further severe complications were not observed in any patient and all stents remained into the stomach. CONCLUSION: Complications arising from migrated esophageal stents are uncommon. Further studies are warranted to determine which patients with migrated SEMS warrant stent retrieval.     

食管带膜支架治疗食管恶性梗阻12例

目的探讨置入食管带膜支架治疗食管恶性狭窄患者的疗效。方法采用内镜下植入食管带膜支架术。结果内镜下一次放置食管支架成功率为100％，术后吞咽困难明显好转，治疗近期有效率100％。结论带膜支架置入对食管恶性梗阻患者是一种安全有效的治疗方法。     

暂时性金属裸支架治疗晚期肺癌中心气道狭窄的探讨

目的观察经可弯曲支气管镜置入呼吸道暂时性镍钛合金裸支架治疗肺癌中心气道狭窄的临床疗效和安全性。方法 38例伴有气管、主支气管外压性狭窄为主的晚期肺癌患者,确诊后先予置入暂时性国产镍钛合金裸支架。置入支架前生活质量Karnofsky评分为42±13(x珋±s),气促指数为2.9±0.7。支架通过支气管镜直视下定位释放置入,通过上拉线取出法或下拉线取出法取出支架。结果 38例每例均置入1枚支架,均一次成功置入。支架置入后狭窄管腔均迅速扩大,置入后第2天气促指数、Karnofsky评分与置入前比较均有显著性差异(P<0.01)。支架置入后均行放疗或/和化疗,支架于置入后1～3个月予取出。未见与支架置入及取出相关的严重并发症。结论暂时性金属裸支架治疗晚期肺癌中心气道狭窄疗效确切,为后续的放化疗创造了条件,同时避免了支架长期放置的并发症,且支架的置入及取出操作简单安全,值得临床推广应用。     

Self‐expandable metal stents for malignant esophageal obstruction: a comparative study between extrinsic and intrinsic compression

Self‐expandable metal stents (SEMSs) are effective for malignant esophageal obstruction, but usefulness of SEMSs in extrinsic lesions is yet to be elucidated. This study is aimed at evaluating the clinical usefulness of SEMSs in the extrinsic compression compared with intrinsic. A retrospective review was conducted for 105 patients (intrinsic, 85; extrinsic, 20) with malignant esophageal obstruction who underwent endoscopic SEMSs placement. Technical and clinical success rates were evaluated and clinical outcomes were compared between extrinsic and intrinsic group. Extrinsic group was mostly pulmonary origin. Overall technical and clinical success rate was 100% and 91%, respectively, without immediate complications. Extrinsic and intrinsic group did not differ significantly in clinical success rate. The median stent patency time was 131.3 ± 85.8 days in intrinsic group while that of extrinsic was 54.6 ± 45.1 due to shorter survival after stent insertion. The 4‐, 8‐, and 12‐week patency rates were 90.5%, 78.8%, and 64.9% respectively in intrinsic group, while stents of extrinsic group remained patent until death. Uncovered, fully covered, and double‐layered stent were used evenly and the types did not influence patency in both groups. In conclusion, esophageal SEMSs can safely and effectively be used for malignant extrinsic compression as well as intrinsic.