Korean J Pathol.  2003 Aug;37(4):246-254.

c-kitMutation and Immunohistochemical Expression in Gastrointestinal Stromal Tumors

• Kang DW
• Kim JH
• Kim DH
• Kim KH
• Park MJ
• Kang DY

Abstract

BACKGROUND: Gastrointestinal stromal tumor (GIST) is the most common non-epithelial neoplasm arising in the gastrointestinal tract. The aim of this study is to investigate the correlation among the clinicopathologic features, presence of c-kit mutation, and immunohistochemical expression of c-kit in 61 cases of GISTs.
METHODS
We divided the GISTs into three groups as benign, boderline and malignant, according to histologic grade. Exon 11 of the c-kit was amplified by PCR and sequenced. We performed immunohistochemical study for CD117, CD34, vimentin, SMA, desmin, and S-100 protein.
RESULTS
Twenty-one cases were diagnosed as benign GISTs, 14 cases as borderline GISTs, and 26 cases as malignant GISTs. The shape, atypia, cellularity, and necrosis showed good correlations with the histologic grades of the GISTs.Mutations of exon 11 of the c-kit were detected in 3 benign GISTs, 4 borderline GISTs, and 13(%) malignant GISTs. Sequence analysis confirmed the deletion mutation (n=16) and the singlebase pair mutation (n=4). The immunohistochemical stainings showed myogenic differentiation(n=20), neurogenic differentiation (n=15), and neither myogenic or neurogenic differentiation(n=34).
CONCLUSIONS
The GIST is the primitive mesenchymal tumor capable of divergent differentiation, and the mutation of the c-kit is a good parameter for the malignant GIST.

Keyword

Gastrointestinal Stromal Tumor; Protooncogene Protein c-kit; Immunohistochemistry

MeSH Terms

Desmin
Exons
Gastrointestinal Stromal Tumors*
Gastrointestinal Tract
Immunohistochemistry
Necrosis
Polymerase Chain Reaction
S100 Proteins
Sequence Analysis
Sequence Deletion
Vimentin
Desmin
S100 Proteins
Vimentin