Pathophysiology
Gastric GIST is a mesenchymal neoplasm derived from Cajal cells.
Associated syndromes
- Neurofibromatosis type 1
- Carney-Stratakis syndrome
- Familial syndromes related to GIST
Typical Appearance
- Located in the 2nd (muscular mucosa) or 4th layer (muscular propria)
- Subepithelial lesion
- Umbilicated
Markers
- CD117 95% of the time (c-kit positive)
- DOG-1 and CD34
- CD117 negative research PDGFRA
- SMA-Smooth muscle actin
High Risk Factors
- Size greater than 2 cm
- Presence of irregular edges;
- Internal anechoic areas (cystic spaces)
- Echogenic foci
- Heterogeneous pattern
- Regional lymph nodes with malignant characteristics
Treatment
Operate > 2 cm, bleeding, obstruction symptoms.
Asymptomatic tumors <2 cm can be monitored periodically.
Standard treatment: resection with free margins WITHOUT lymphadenectomy.
Neoadjuvant treatment is reserved for borderline or unresectable tumors.
Adjuvant if C-kit positive and
Extra-gastric tumor
- 10 cm
- 10 mitoses per 50 magnification field
- 5cm + >5 mitoses per 50 magnification field
- Capsule rupture
- Recurrence/Metastatic
Possible surgical modalities:
- Wedge resection
- Endogastro surgery (posterior wall)
- Combined resection (VLP+ EDA) (proximal)
- Subtotal gastrectomy + roux-en-Y (antrum and pylorus)
- Antrectomy
References:
Lu Y, Chen L, Wu J, Er L, Shi H, Cheng W, Chen K, Liu Y, Qiu B, Xu Q, Feng Y, Tang N, Wan F, Sun J, Zhi M. Artificial intelligence in endoscopic ultrasonography: risk stratification of gastric gastrointestinal stromal tumors. Therap Adv Gastroenterol. 2023 May 30;16:17562848231177156. doi: 10.1177/17562848231177156. PMID: 37274299; PMCID: PMC10233610.
Current clinical management of gastrointestinal stromal tumor, World J
Gastroenterol. 2018 Jul 14