Learning objectives
In this educational exhibit we propose to achieve these objectives:
To identify the usual CT appearance of GIST
brief notes about the phathophysiology-imaging correlation of the radiological findings.
Background
GISTs are the most frequent neoplastic forms of mesenchymal nature of the gastrointestinal tract and overall represent 1-3% of gastrointestinal tumors in middle or advanced age patient.
GISTs have more frequent localization in the stomach (65%) and small intestine (25%),
rarer in the esophagus,
colon and rectum.
In the stomach the body is the most common site,
followed by the fundus and antrum (1).
They derive from connective stem cells that are differentiated into Cajal cells,
which coordinate the contractions of the gastroenteric wall.
The...
Findings and procedure details
Epidemiology and presentation
There is no reported significant sex difference [3].
Grading of malignancy is a continuum based on assessment of tumor size and mitotic index [4].
The median survival with metastatic GIST has been calculated as 20 months but in those patients with locally recurrent tumor is 9–12 months [3].
Small lesions are rarely symptomatic and are usually benign,
often having been detected incidentally.
Larger mass often demonstrate an exophytic pattern of growth,
toward the peritoneal cavity.
In tumors larger than 2 cm,
the...
Conclusion
GISTs can be multiple and reach large dimensions (30 cm in diameter).
CT is important for diagnosis and staging in the majority of patients.
Other diagnoses must be ruled out and the histological assessment is ultimately necessary for confirmation.
Over the years,
Imatinib has revolutionized the treatment of GIST with the c-KIT mutation.
References
1.Levy AD,
Remotti HE,
Thompson WM,
Sobin LH,
Miettinen M.
Gastrointestinal stromal tumors: radiologic features with pathologic correlation.
RadioGraphics 2003;23(2):283-304.
2.Sarlomo-Rikala M,
Kovatich AJ,
Barusevicius A,
Miettinen M.
CD117: A sensitive marker for gastrointestinal stromal tumors that is more specific than CD34.Mod Pathol.1998;11:728–34.
3.Graadt van Roggen JF,
van Velthuysen ML,
Hogendoorn PC.
The histopathological differential diagnosis of gastrointestinal stromal tumours.
J Clin Pathol.
2001;54:96–102.
4.Fletcher CD,
Berman JJ,
Corless C,
Gorstein F,
Lasota J,
Longley BJ,
Miettinen M,
O'Leary TJ,
Remotti H,
Rubin BP,
Shmookler...