Proof of concept for stereotactic body radiation therapy in the treatment of functional neuroendocrine neoplasms.

Dysregulated hormonal production remains a challenge in the management of neuroendocrine neoplasms (NEN). We report 4 cases of patients with functional NEN treated with stereotactic body radiation therapy (SBRT) to either the primary/dominant metastatic site of disease or the end organ of hormonal release. No significant toxicities were observed during or after treatment. Each patient has had biochemical, clinical and radiographic response to therapy, providing proof of concept that SBRT is an effective therapeutic strategy for functional neuroendocrine neoplasms.