Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm of the gastrointestinal tract. The main treatment for localized gastrointestinal stromal tumors is surgical resection. Unresectable or advanced GIST are poorly responsive to conventional cytotoxic chemotherapy but the introduction of tyrosine kinase inhibitors (TKIs) marked a revolutionary step in the treatment of these patients, radically improving prognosis and clinical benefit. Historically GIST has been considered radiation-resistant, and the role of radiotherapy in the management of patients with GIST is currently restricted to symptomatic palliation in current treatment guidelines. Here we report two patients affected by metastatic GIST, treated with radiotherapy and radiosurgery in combination with TKIs, achieving an unexpected objective response in the first case and a significant clinical benefit associated with a local tumor control of several months in the second case. These and other successful experiences that are progressively accumulating, open up new scenarios of use of radiation therapy in various settings of treatment. GIST is not universally radioresistant and radiotherapy, especially if combined with molecularly targeted therapy, can improve the outcomes for patients diagnosed with GIST.