Durable tumor regression in highly refractory metastatic wild-type GIST following treatment with nivolumab.

Gastrointestinal stromal tumor (GIST) is a devastating disease, especially in the setting of metastasis. The natural progression of GIST has been significantly altered by the development of small molecule tyrosine kinase inhibitors (TKIs), including imatinib, sunitinib, and regorafenib, all of which are FDA approved. However, TKIs are not always well-tolerated, and the refractory disease continues to be a problem.