Hedenstrom P, et al. – This research aspired to assess endoscopic ultrasound (EUS)–guided biopsies for the pretreatment characterization of gastrointestinal stromal tumors (GIST) to personalize the management of patients. For the pretreatment diagnosis and characterization of GISTs, EUS–guided biopsy sampling was accurate and allowed the prediction and evaluation of tumor response to neoadjuvant imatinib therapy.