111 In-Pentetreotide-Guided Radiosurgery for Intraoperative Localization of Retroperitoneal Nodal Metastasis in a Patient With Ileal Neuroendocrine Tumor.

ABSTRACT: 64 Cu-DOTATATE PET/CT of a 44-year-old man with an ileal neuroendocrine tumor demonstrated the primary tumor, local nodal metastases, and a pericaval nodal metastasis. Localization of the pericaval node during surgery may be difficult, thus 4.4 mCi of 111 In-pentetreotide was administered before surgery to assist with localization and resection. At surgery, the pericaval nodal metastasis was readily detected by gamma probe, which could then be resected and pathologically proven to be a metastasis. This demonstrates the use of somatostatin receptor-targeted imaging for intraoperative localization of an otherwise difficult to surgically localize metastasis. Without intraoperative somatostatin receptor-targeted radiosurgery, disease may have been incompletely resected.