Stomach GIST

Case contribution: Dr Radhiana Hassan


  • A 75 years old man
  • Underlying HPT, dyslipidaemia
  • History of open left hernioplasty 5 years ago
  • Presented with abdominal swelling for one week
  • Associated with abdominal pain, colicky in nature, no constitutional symptoms, no altered bowel habit, no fever
  • Clinical examination shows a left hypochondriac mass, tender, no splenomegaly
Abdominal radiograph

Radiograph findings:

  • Soft tissue density at left lumbar region
  • Paucity of bowel gas at this region
  • No fluid levels or calcification within
  • No dilated bowel loops
Ultrasound abdomen

Ultrasound findings:

  • There is a large heterogenous solid cystic mass occupying the left hypochondriac area.
  • The cystic components have internal septations within them.
  • No internal calcification seen.
  • There is scanty vascularity detected on colour Doppler examination.
  • The mass is seen adjacent to the tail of the pancreas and pushing the left kidney posteriorly. Otherwise the pancreas is normal.
  • The mass is also seen touching the posterior margin of the left liver lobe.
CT scan abdomen in axial plane soft tissue window post contrast

CT scan findings:

  • A large heterogeneous multi-lobulated peripherally enhancing mass (mean HU 21) is seen in the left hypochondrium and lumbar region.
  • This mass collectively measures about 9.8 cm x 14.7 cm x 19.2 cm (AP x W x CC).
  • Large areas of central hypodensity are noted, most likely central necrosis.
  • The superior part of the mass appears more cystic with HU of 18 – 30.
  • Multiple vessels are also seen in between these structures, particularly at the anteroinferior aspect (red arrows).
  • No fat component or calcification is seen within this mass. No fluid-fluid level is seen.
  • The mass show claw-sign to the adjacent stomach, in which possible it arise from the wall of the stomach. The stomach is compressed posteriorly by the mass.
  • The mass is also seen displacing the pancreas, splenic vein and left kidney posteriorly.
  • The mass also displaces the bowel loops medially and inferiorly. Clear fat plane with adjacent bowel loops is seen.
  • No bowel dilatation or bowel wall thickening is identified

Progress of patient:

  • Tumour marker Ca19.9, AFP 3.8, CEA 1.2
  • OGDS: antral gastritis
  • Colonoscopy: normal

Intraoperative findings:

  • Huge solid cystic mass occupying the lesser sac, pushing the stomach anteriorly and the transverse colon inferiorly
  • Mass cystic in nature and highly vascularized
  • Tumour densely infiltrate the posterior part of stomach at the greater curvature and tail of pancreas
  • Multiple mesenteric and omentum nodules seen
  • Semi-emergency laparotomy, sleeve gastrectomy and distal pancreatotomy done

HPE findings:

  • Cystic tumour: gastrointestinal stromal tumour (GIST) of the stomach. TNM stage pT4pN0pM1.
  • Tumour perforation is present.
  • No lymphovascular or perineural invasion noted. No evidence of nodal involvement.
  • Tumour deposit on the splenic capsule
  • Metastatic GIST to omentum and mesenteric nodule
  • Falciform ligament: no evidence of malignancy/metastasis


  • Gastrointestinal stromal tumors (GISTs) are soft tissue sarcomas that can be located in any part of the digestive system.
  • Their most common sites are the stomach and small intestine.
  • The peak age for GIST of the stomach is around 60 years and a slight male preponderance is reported.
  • Symptoms at presentation usually include bleeding, abdominal pain or abdominal mass.
  • Endoscopically, they typically appear as a submucosal mass with or without ulceration
  • on CT scans an extragastric mass is usually seen. They are rounded with frequent hemorrhage. Larger tumors may also demonstrate necrosis and cystic change. Size is variable, ranging from 1 to 30 cm.
  • Typically the mass is of soft tissue density with central areas of lower density when necrosis is present (usually in larger tumors) that occasionally appear as fluid-fluid levels.
  • Enhancement is typically peripheral (due to central necrosis).
  • Calcification is uncommon (3%).
  • Metastases (distant, peritoneal, omental) or direct invasion into adjacent organs may be seen in more aggressive lesions. Lymph node enlargement is not a feature.
  • The diagnosis of malignant GIST requires histopathologic analysis, but certain characteristics suggest malignancy, which develops in 10-30% of these lesions. These include exogastric growth, diameter >5 cm, central necrosis, and extension to other organs.
Author: radhianahassan