Learning objectives
Our aim is to show the main radiological features of GISTs,
with particular regard to their complications,
to increase familiarity to the different clinical and radiological manifestations of these tumors and to ensure an accurate and early diagnosis,
essential for treatment.
Background
GISTs are the most common mesenchimal neoplasms of the gastrointestinal (GI) tract but are nevertheless rare tumors,
accounting for around 1% of all GI neoplasms.
Previously classified as GI leiomyomas and leiomyosarcomas,
because of the apparent origin from the muscularis propria layer of the intestinal wall,
GISTs are now known to be derived from interstitial cells of Cajal,
the pacemaker cells of the GI tract.
The pathogenesis is the result of activating mutations of the genes encoding promoting tumor survival and growth,
such as the...
Findings and procedure details
GISTs are well-defined masses arising within the muscolaris propria layer of GI wall,
with variable size.
Intramural in origin,
they may grow exophytically,
projecting into the abdominal cavity and displacing adjiacent organs,
or grow intraluminally,
potentially compromising lumen patency.
They often show overlying mucosal ulceration; focal areas of hemorrhage,
cystic degeneration and necrosis may occur,
particularly in larger lesions.
Different imaging modalities can be used to accurately detect and characterize GISTs.
Ultrasonography
On ultrasound,
GISTs appear as hypoechoic,
well-demarcated masses,
heterogeneous because of the presence...
Conclusion
The occurrence of complications associated with GISTs may require urgent surgery.
Early diagnosis and appropriate treatment strategy can be lifesaving: in order to a correct diagnosis and to take active participation in patient management,
radiologist should become familiar with the most typical radiological pitfalls of the diagnosis of GISTs and with the main radiological features of their complications.
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GI Stromal Tumors: 15 Years of Lessons...