From the Guidelines
The most common cause of gastric outlet obstruction is pancreas head cancer (option 2). Pancreatic adenocarcinoma of the head of the pancreas frequently causes gastric outlet obstruction due to its anatomical location adjacent to the duodenum and pylorus. As the tumor grows, it can directly invade or extrinsically compress the gastric outlet, leading to mechanical obstruction. This obstruction typically presents with symptoms such as persistent vomiting (often containing undigested food), early satiety, epigastric pain, and weight loss. According to the study by 1, malignant gastric outlet obstructions are usually due to stricturing at the level of the pylorus or duodenum and are most commonly caused by malignancies involving the pancreas, stomach, duodenum, ampulla, or biliary tree.
The study by 1 also supports this, stating that malignancy is now the most common cause of gastric outlet obstruction in adults. While annular pancreas can cause congenital gastric outlet obstruction (typically presenting in infancy), and metastasis from colon cancer can occasionally cause gastric outlet obstruction, neither is as common as primary pancreatic head cancer in adult patients with this condition. The management of malignant gastric obstruction should be individualized, and treatment options should be selected as clinically appropriate, as stated in the study by 1.
Some key points to consider in the management of gastric outlet obstruction include:
- Alleviating or bypassing the obstruction
- Reducing symptoms of obstruction via venting gastrostomy
- Placement of enteral stent for relief of outlet obstruction
- Surgery, such as gastrojejunostomy or gastrectomy in select patients
- EBRT and chemotherapy, as mentioned in the study by 1.
Overall, pancreas head cancer is the most common cause of gastric outlet obstruction, and its management should be tailored to the individual patient's needs, taking into account the severity of symptoms, tumor location, and overall prognosis, as supported by the studies by 1, 1, 1, and 1.
From the Research
Causes of Gastric Outlet Obstruction
- The most common cause of gastric outlet obstruction is not explicitly stated in the provided studies as one of the options (annular pancreas, pancreas head cancer, metastasis from colon cancer)
- However, according to the study 2, peptic ulcer disease is the most common cause of benign gastric outlet obstruction, and malignant causes include gastric cancer, lymphoma, and gastrointestinal stromal tumor
- Pancreatic cancer is also a cause of gastric outlet obstruction, as mentioned in the studies 3 and 4
- Gastric cancer is another cause of gastric outlet obstruction, as discussed in the studies 4 and 5
Comparison of Treatment Options
- The studies 6, 2, 3, 4, and 5 discuss various treatment options for gastric outlet obstruction, including endoscopic stenting, gastrojejunostomy, and palliative resection
- The study 5 compares the outcomes of gastrojejunostomy with endoscopic stenting for the treatment of gastric outlet obstruction caused by gastric cancer, and finds that both procedures are effective, but with different advantages and disadvantages
- The study 4 compares the results of endoscopic stenting, palliative resection, and gastrojejunostomy as palliation of gastric outlet obstruction in gastric cancer, and finds that palliative resection seems to provide a survival benefit, while endoscopic stenting provides rapid and efficient palliation for patients unfit for surgery
Treatment Outcomes
- The study 3 finds that duodenal stenting results in an earlier discharge from hospital and possibly improved survival compared to gastrojejunostomy in patients with pancreatic cancer and gastric outlet obstruction
- The study 5 finds that endoscopic stenting is associated with better short-term outcomes, including shorter procedure time, faster resumption of oral intake, and shorter duration of hospital stay, while gastrojejunostomy is preferable in terms of its lower rate of stent-related complications, re-obstruction, and reintervention.