Differential diagnosis of gastrointestinal leiomyoma versus gastrointestinal stromal tumor.
BACKGROUND
Strategies for the diagnosis of tumors arising in the intestinal muscular wall are rapidly evolving. Immunoreactivity for CD117 (KIT) usually supports the diagnosis of gastrointestinal stromal tumor (GIST), but a small subset of GISTs lacks KIT expression. In these cases the differential diagnosis of KIT-negative GIST versus one of their morphological mimics is difficult and bears critical implications for therapeutic management.


METHODS
Here, we report a case of a KIT-negative smooth muscle cell tumor of the colon in a 21-year-old man with the clinical appearance of GIST. Mutations of the KIT and platelet-derived growth factor receptor alpha (PDGFRA) gene could be ruled out. No chromosomal imbalances characteristic of GIST were found. However, cytogenetic analysis revealed losses at 7q, which has previously been reported in cases of uterine leiomyoma.


CONCLUSIONS
We discuss current approaches to the differential diagnosis of true gastrointestinal smooth muscle cell tumor versus GIST.
Kuhlgatz
Jens
J
Department of General and Visceral Surgery, Albert Schweitzer Hospital, Northeim, Germany.
Sander
Bjoern
B
Golas
Mariola Monika
MM
Gunawan
Bastian
B
Schulze
Thorsten
T
Schulten
Hans-Jürgen
HJ
Wardelmann
Eva
E
Füzesi
László
L
D000328:Adult; D001707:Biopsy, Needle; D003082:Colectomy / Q000379:methods; D004252:DNA Mutational Analysis; D003937:Diagnosis, Differential; D046152:Gastrointestinal Stromal Tumors / Q000175:diagnosis* / Q000235:genetics / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D007813:Laparotomy / Q000379:methods; D007889:Leiomyoma / Q000175:diagnosis* / Q000235:genetics / Q000601:surgery; D008297:Male; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics*; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000235:genetics*; D018570:Risk Assessment; D012811:Sigmoid Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000601:surgery; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D018608:Ultrasonography, Doppler
D019009:Proto-Oncogene Proteins c-kit; D020796:Receptor, Platelet-Derived Growth Factor alpha