Background: CD44 is a transmembrane glycoprotein belonging to the cell-adhesion molecule family. It has been identified as being involved in tumor progression and metastasis, and its expression has been found to be of prognostic significance in several human malignancies. The aim of this study was to assess CD44 expression in gastrointestinal stromal tumors (GISTs), the most common mesenchymal tumor of the gastrointestinal tract.
Methods: Between January 1995 and March 2006, 92 patients undergoing surgical resection for GIST in National Cheng Kung University Hospital were evaluated. To study the significance of CD44 expression, immunohistochemical staining of CD44 in tumor specimens was performed, and the clinicopathological information of patients was reviewed.
Results: Fifty-nine of 81 patients (73%) showed positive CD44 expression. Loss of CD44 expression was associated with disease progression (p = 0.019). Kaplan-Meier analysis revealed better progression-free survival among patients with strong CD44 expression (++ and +++) (p = 0.034), absence of disease progression (p < 0.001), and lower risk, according to National Institutes of Health (NIH) Consensus Criteria for GIST risk stratification (p = 0.003). Multivariate analysis demonstrated that high-risk status was the only independent risk factor for disease progression and the only independent predictor for a poor progression-free survival (p = 0.023 and 0.045, respectively).
Conclusions: It is demonstrated that high-risk status by NIH criteria is significantly associated with disease progression and poor progression-free survival in GIST.