Feasibility of Elastography for Preoperative Prediction of Malignancy of Gastrointestinal Stromal Tumor of the Stomach

BACKGROUND/AIM: There are several well-known classifications for determining the grade of malignancy of gastrointestinal stromal tumor (GIST), but these classifications depend exclusively on invasive methods, including biopsy. Therefore, a minimally invasive examination modality is needed to preoperatively predict the malignant potential of GIST. The aim of this retrospective study was to clarify the utility of elastography using endoscopic ultrasonography for preoperatively predicting the malignant potential of GIST of the stomach. PATIENTS AND METHODS: Of 66 patients who underwent surgery for GIST of the stomach at our hospital between 2019 and 2025, 43 patients preoperatively subjected to elastography using endoscopic ultrasonography were enrolled in this study. Malignant potential was classified using modified Fletcher's classification. RESULTS: Of the 43 patients, four were classified as having high recurrence risk, six intermediate, 23 low, and 10 very low risk. The strain ratio was significantly lower in the high + intermediate risk group than in the low + very low risk group, with a cut-off value of 8.295 (sensitivity 70.0%, specificity 81.25%) calculated by receiver-operating characteristic curve analysis. Further, the elastic scores of the low + very low risk group were mostly 3 and 4, whereas almost all patients except one in the high + intermediate risk group had a score of 5, with none having a score of 3. CONCLUSION: The strain ratio and elastic score calculated by elastography using endoscopic ultrasonography are potentially useful, non-invasive indicators for preoperatively predicting the malignancy of GIST of the stomach.