How often are gist malignant?

Gastrointestinal stromal tumors (GISTs) can be malignant, but the majority are benign. Approximately 50% to 70% of GISTs are considered malignant based on size, mitotic rate, and location. Tumors that are larger than 5 cm or have a high mitotic index are more likely to be aggressive. Regular monitoring and appropriate treatment are essential for managing malignant GISTs.