What Are Submucosal Lesions?
Submucosal lesions are growths located under the mucosal layer. When present in the gastrointestinal tract, they may appear as protuberances in the lumen. Most submucosal lesions are asymptomatic and are found incidentally during routine endoscopy or radiographic imaging studies.
The different types of submucosal lesions include:
- Gastrointestinal Stromal Tumors (GISTs): They usually occur in the 5th and 6th decades of life and commonly occur in the stomach and small intestine. They vary in size with the large tumors being more symptomatic. Symptoms include gastrointestinal tract bleeding due to mucosal ulceration, abdominal pain, bowel obstruction, and anorexia. About 10% of all GISTs may be malignant. Complete surgical resection is the treatment of choice for malignant or symptomatic GISTs.
- Leiomyomas: They are benign tumors that occur usually in the distal end of the esophagus. These lesions are mostly small and asymptomatic. Sometimes, they can cause dysphagia. Asymptomatic tumors do not require any treatment. Surgical removal is indicated in case of a symptomatic leiomyoma.
- Lipomas: They are benign tumors containing fat and can occur anywhere in the GI tract. Lipomas are usually benign and asymptomatic; however, they may occasionally cause obstruction, abdominal pain, and bleeding. Surgical removal is required only in case of symptomatic and enlarging lipomas.
- Granular Cell Tumors: They are rare neoplasms. When occurring in the GI tract, they are usually found in the oropharynx and esophagus. The treatment is surgical resection for large, symptomatic, and malignant lesions. Small, non-malignant lesions should be monitored regularly.
- Duplication Cysts: They are rare birth defects located within the GI tract, commonly found in the colon, ileum, and esophagus. They are usually asymptomatic and found on incidental radiographic imaging or endoscopy. Occasionally, they may cause abdominal pain, vomiting, dysphagia, obstruction, hemorrhage, perforation, pancreatitis, and jaundice. Treatments include fine-needle aspiration and surgical excision.
- Carcinoid Tumors: They arise from endocrine and nerve tissue. They can be either benign or malignant. When present within the gastrointestinal system, they commonly occur near the appendix, ileum, and rectal area. They may cause symptoms of diarrhea, constipation, and abdominal pain. Surgical resection with regular monitoring is the treatment of choice.
- Ectopic Pancreas: These are lesions that contain pancreatic tissue and may be found in the distal stomach, jejunum, and duodenum. Mostly, these lesions are asymptomatic. In a few cases, there may be symptoms of pancreatitis, obstruction, bleeding, and malignant change. Treatment options range from observation to surgical resection depending on the severity of the condition.