背景: 上消化道癌症可能造成惡性胃腸道阻塞，利用內視鏡術在流動X光之下安置自動擴張型金屬支架，將惡性腸道狹窄擴張來做為治療方式是目前主流的做法之一，但是能否維持支架的暢通的時間，卻是相當分歧。過去很多回溯型的研究發現可能影響支架暢通的因子包含 : 腹膜轉移，腹水，病患活動表現，支架擴張的程度。然而這些研究所分析出因子缺乏一致性，對於腸道金屬支架所置放的作法，也並未有因為這些分析能夠提供做為臨床指引的建議與依據。
目標:
1. 分析金屬支架在第七天或是第三十天何者對於長期的預後是較為可靠的早期里程碑
2. 找出腸道金屬支架在早期里程中有那些不良的預後因子。
方法: 利用成大醫院在2018至2020所針對惡性胃腸道狹窄施作腸道金屬支架的病患，針對病患的各項指標，癌別，以及針對惡性狹窄的不同進行分析。
結果: 在金屬支架置入後第三十天對於長期預後的預測優於第七天，可以作為評估支架成效的早期里程碑，然而對於早期里程碑的評估，在轉移癌，遠端狹窄，予支架擴張為其不良預後因子。

Background:
Malignant gastric outlet obstruction is one of serious complication resulted from primary or metastatic upper gastrointestinal cancer. Palliative treatment of gastric outlet obstruction including bypass surgery, endoscopic stenting, or total parenteral nutrition. Self-expandable metal stent is applied for treatment of malignant stricture of gastrointestinal tracts by endoscopy with or without fluoroscopy. The patency of metal stent was variable. Peritoneal carcinomatosis, ascites, patient performance status, chemotherapy, and effective stent opening were considered as factors of stent patency but not inconsistence. Besides, there is not yet recommendation of guideline for enteral stent placement by those risk factors.
Hypothesis:
Characteristic of stricture like cancer type, location, stricture length, and metal stent performance may be possible prognostic factors of stent patency. Otherwise, the stent function at day 7 may not be set as an end point of stent success.
Aim:
1. To define stent function at day 7 or day 30 be a good reference for long term stent patency.
2. To identify prognostic factors of patency of enteral metal stent.
Material and method:
Patients with malignant gastric outlet obstruction bear endoscopic metal stenting was enrolled in National Cheng Kung University Hospital from 2018 to 2020 retrospectively. Characteristic of patients, cancers, and malignant stricture of guts, and metal stenting were analyzed. Gastric Outlet Obstruction Scoring System (GOOSS) was used for assessment of successful treatment.
Results:
Total fifty-one patients with 26 men and 25 women (age: 61.2 +/- 12.9 years old) were enrolled finally. The technically successful rate was 100%, and clinical successful rate was 78.4%. The patency of metal stent at D30 is better than D7 for prediction of long-term stent success. Among the failed metal stenting at day 7 around 23.5% still may succeed at D30 (66.7%). The predictor of failed metal stenting at Day 30 are metastatic malignancy, distal duodenal obstruction, and poor stent opening less than 8mm.
Conclusion: For patient with malignant gastric outlet obstruction due to metastatic disease, distal obstruction, or poor stent opening, combining other intervention rather than single metal stenting maybe needed
Keyword: endoscopy, gastric outlet obstruction, metal stent,

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