The New Horizon In Gist and Net Management.
dr. N Srie Laksminingsih, Sp.Rad
GIST : Gastro Intestinal Stromal Tumor
GISTs were misdiagnosed as smooth muscle
tumors because on light microscopy the two
tumors share many features
Originate from cells of Cajal pacemaker
cells that are involved in the regulation of gut
motility
Characterized by expression of a tyrosine
kinase growth factor receptor, also called kit
receptor or CD117
50 y.o, woman,
small-bowel GIST
Histopathologic:
typical GIST
composed of
fascicles of
nondescript spindle
cells.
H and E stain:
similar to that of
smooth muscle
tumor.
The most common mesenchymal tumors to
arise from the gastrointestinal tract
40–70 years old
Male ≈ female
Approximately
Benign (70-80%)
Malignant (20-30%)
Organ of origin
Stomach (60-70%) the most common site
Small intestine (20-30%)
Colon and rectum (5-10%)
Esophagus (
Growth pattern
Endoluminal
Exophytic
Mixed
Border
Enhancement pattern: depends on size
95% well defined
Heterogenous (Large)
Homogenous (Small)
Imaging modalities
Conventional
abdominal radiography, barium study
Ultrasound
CT scan
MRI
PET scan
Radiographic features of GIST vary depending
on the size of the tumor and the organ of origin
GIST detectable:
Large enough (density, not specific)
Calcified (25% cases)
(GIST with multiple calcifications in sigmoid colon)
Rounded filling defect -> endoluminal mass
Ulceration -> in larger masses
Typically hypoechoic
Usually difficult to identify organ of origin
Peritoneal GIST. Axial
contrast-enhanced CT
scan in 65-year-old
male shows multiple
heterogeneously
enhancing peritoneal
masses (arrows)
Common: liver and peritoneal cavity via
hematogenous spread and peritoneal seeding.
Occasional: soft tissues, lungs, and pleura
Marla et al:
Tumors that enhanced homogenously (nine out of
53 cases in their series) showed no metastases (2.6
years) as compared with those that enhanced
heterogeneously
50-year-old woman
with gastric
gastrointestinal
stromal tumor. Axial
contrast-enhanced CT
scan of liver reveals
hypovascular (arrow)
and hypervascular
(arrowhead)
metastases
Coronal contrastenhanced CT scan in a
39-year-old male
operated for gastric
GIST shows metastasis
(arrow) in the left lobe
of the liver
GIST are the most common mesenchymal tumors of the
digestive tract
The most common site is the stomach followed by the
small intestine
Radiological features are intramural mass, exophytic
large and heterogeneous contrast enhancement
Approximately 70-80% benign and 20-30% malignant
Malignant GIST are lesion > 5 cm, indistinct margins,
irregular surface, heterogeneous contrast enhancement,
component necrotic-cystic, tissue invasion, hepatic
metastases, peritoneal dissemination
Kim JY, et al. Ectopic pancreas: CT findings with emphasis on
differentiation from small gastrointestinal stromal tumor and
leiomyoma. Radiology. 2009 Jul;252(1):92-100.
Levy AD, Remotti HE, Thompson WM, Sobin LH, Miettinen M.
Gastrointestinal stromal tumors: radiologic features with pathologic
correlation. RadioGraphics 2003; 23:283–304.
Rana R, et al. Calcified gastrointestinal stromal tumor of the sigmoid
colon mimicking inspissated barium on CT. AJR Am J Roentgenol. 2006
Sep;187(3):W322-3.
Sripathi S, et al. CT features, mimics and atypical presentations of
gastrointestinal stromal tumor (GIST). Indian J Radiol Imaging
2011;21:176-81.
Stamatakos M, Douzinas E, Stefanaki C, Safioleas P, Polyzou E, Levidou
G, Safioleas M. Gastrointestinal stromal tumor. World Journal of Surgical
Oncology 2009, 7:61.
GIST : Gastro Intestinal Stromal Tumor
GISTs were misdiagnosed as smooth muscle
tumors because on light microscopy the two
tumors share many features
Originate from cells of Cajal pacemaker
cells that are involved in the regulation of gut
motility
Characterized by expression of a tyrosine
kinase growth factor receptor, also called kit
receptor or CD117
50 y.o, woman,
small-bowel GIST
Histopathologic:
typical GIST
composed of
fascicles of
nondescript spindle
cells.
H and E stain:
similar to that of
smooth muscle
tumor.
The most common mesenchymal tumors to
arise from the gastrointestinal tract
40–70 years old
Male ≈ female
Approximately
Benign (70-80%)
Malignant (20-30%)
Organ of origin
Stomach (60-70%) the most common site
Small intestine (20-30%)
Colon and rectum (5-10%)
Esophagus (
Growth pattern
Endoluminal
Exophytic
Mixed
Border
Enhancement pattern: depends on size
95% well defined
Heterogenous (Large)
Homogenous (Small)
Imaging modalities
Conventional
abdominal radiography, barium study
Ultrasound
CT scan
MRI
PET scan
Radiographic features of GIST vary depending
on the size of the tumor and the organ of origin
GIST detectable:
Large enough (density, not specific)
Calcified (25% cases)
(GIST with multiple calcifications in sigmoid colon)
Rounded filling defect -> endoluminal mass
Ulceration -> in larger masses
Typically hypoechoic
Usually difficult to identify organ of origin
Peritoneal GIST. Axial
contrast-enhanced CT
scan in 65-year-old
male shows multiple
heterogeneously
enhancing peritoneal
masses (arrows)
Common: liver and peritoneal cavity via
hematogenous spread and peritoneal seeding.
Occasional: soft tissues, lungs, and pleura
Marla et al:
Tumors that enhanced homogenously (nine out of
53 cases in their series) showed no metastases (2.6
years) as compared with those that enhanced
heterogeneously
50-year-old woman
with gastric
gastrointestinal
stromal tumor. Axial
contrast-enhanced CT
scan of liver reveals
hypovascular (arrow)
and hypervascular
(arrowhead)
metastases
Coronal contrastenhanced CT scan in a
39-year-old male
operated for gastric
GIST shows metastasis
(arrow) in the left lobe
of the liver
GIST are the most common mesenchymal tumors of the
digestive tract
The most common site is the stomach followed by the
small intestine
Radiological features are intramural mass, exophytic
large and heterogeneous contrast enhancement
Approximately 70-80% benign and 20-30% malignant
Malignant GIST are lesion > 5 cm, indistinct margins,
irregular surface, heterogeneous contrast enhancement,
component necrotic-cystic, tissue invasion, hepatic
metastases, peritoneal dissemination
Kim JY, et al. Ectopic pancreas: CT findings with emphasis on
differentiation from small gastrointestinal stromal tumor and
leiomyoma. Radiology. 2009 Jul;252(1):92-100.
Levy AD, Remotti HE, Thompson WM, Sobin LH, Miettinen M.
Gastrointestinal stromal tumors: radiologic features with pathologic
correlation. RadioGraphics 2003; 23:283–304.
Rana R, et al. Calcified gastrointestinal stromal tumor of the sigmoid
colon mimicking inspissated barium on CT. AJR Am J Roentgenol. 2006
Sep;187(3):W322-3.
Sripathi S, et al. CT features, mimics and atypical presentations of
gastrointestinal stromal tumor (GIST). Indian J Radiol Imaging
2011;21:176-81.
Stamatakos M, Douzinas E, Stefanaki C, Safioleas P, Polyzou E, Levidou
G, Safioleas M. Gastrointestinal stromal tumor. World Journal of Surgical
Oncology 2009, 7:61.