What is the management approach for gastric leiomyoma (gastric smooth muscle tumor)?

Management of Gastric Leiomyoma

Primary Recommendation

Asymptomatic gastric leiomyomas that are histologically confirmed do not require routine resection or surveillance, as they are benign tumors with minimal risk of malignant transformation. 1

Diagnostic Confirmation

The critical first step is distinguishing leiomyoma from gastrointestinal stromal tumor (GIST), as management differs substantially:

• Tissue sampling using fine needle aspiration (FNA) or fine needle biopsy (FNB) is essential to differentiate leiomyoma from GIST, which requires different management 1
• Leiomyomas stain positive for smooth muscle actin and desmin, while negative for CD117, CD34, and S100 protein 1
• True gastric leiomyomas are actually quite rare—most historical "leiomyomas" were misclassified GISTs before modern immunohistochemistry became available 1

Management Algorithm Based on Clinical Presentation

For Asymptomatic Lesions with Confirmed Leiomyoma Histology:

• No resection or surveillance is required 1
• A 2024 study of 231 histologically proven gastric leiomyomas followed over median 50.8 months showed only 2.4% increased in size, with one being leiomyosarcoma 2
• Close monitoring with routine follow-up without resection is sufficient for most cases, even large-sized lesions 2

For Symptomatic Lesions (bleeding, pain, obstruction):

Resection is indicated 1, with approach determined by location:

Anterior wall, lesser/greater curvature, or fundus:

• Laparoscopic wedge resection without gastrotomy is the preferred approach 3
• This minimally invasive technique provides excellent outcomes with rapid recovery 3

Posterior gastric wall:

• Two options: laparoscopic wedge resection with gastrotomy ("transgastric approach") or laparoscopic intragastric resection ("intragastric approach") 3, 4
• Both approaches allow complete tumor removal with minimal morbidity 4

Gastroesophageal junction:

• Laparoscopic enucleation is the approach of choice 3
• For large symptomatic lesions, robotic-assisted endoluminal resection is emerging as a stomach-preserving alternative to total gastrectomy 5
• This avoids the significant morbidity of esophagojejunostomy and preserves quality of life 5

For Lesions with Concerning Features:

If ulceration or size increase is documented:

• Resection is beneficial to rule out malignant transformation 2
• One case in the 2024 study showed leiomyosarcoma in a growing lesion 2

Critical Pitfalls to Avoid

• Do not assume all gastric smooth muscle tumors are benign leiomyomas—histologic confirmation distinguishing from GIST is mandatory, as GISTs require different management including potential adjuvant therapy 1
• Avoid unnecessary resection of confirmed asymptomatic leiomyomas—the natural history data shows these are truly benign with minimal growth potential 2
• Do not perform extensive resections (total gastrectomy) for benign disease when minimally invasive enucleation or wedge resection is feasible 6, 3
• Ensure complete histologic evaluation when resection is performed—band ligation techniques that allow tumor sloughing prevent adequate pathologic assessment 1

Endoscopic Resection Considerations

For select small lesions arising from the muscularis propria:

• Endoscopic resection techniques (ESD, EMR) have been described with acceptable complication rates 1
• However, complete resection must be confirmed, as incomplete removal of premalignant lesions is concerning 1
• Laparoscopic-assisted endoscopic resection combines benefits of both approaches for lesions near the gastroesophageal junction 7