gallium-ga-68-dotatate and Appendiceal-Neoplasms

Appendiceal neuroendocrine neoplasms (appNEN) generally carry a low recurrence risk. Ga-DOTATATE positron emission tomography (DOTA PET) is increasingly used as it is more sensitive than cross-sectional imaging. We hypothesize that early DOTA PET is unlikely to detect recurrent disease in patients with low-risk resected appNEN because of the delayed pattern of recurrence.. Retrospective study (dual review) of patients undergoing DOTA PET 0 to 18 months after resected appNEN. The primary outcome was the proportion of scans demonstrating residual disease.. Forty-one patients were included (median age, 29 years; 63% female), most with small, low-grade appNEN. No scans (0%) showed residual/distant disease. Eight (20%) of 41 scans showed indeterminate findings requiring follow-up. Five (12%) scans were recommended for follow-up with modalities other than DOTA PET (vertebra, 3; thyroid; bone, 1 each). Three (7%) were recommended for follow-up with DOTA PET (all with indeterminate abdominal uptake). These 3 patients had no recurrent disease on follow-up.. The Ga-DOTATATE PET is of no value when performed in the first 18 months after resected appNEN. Although 20% of scans showed indeterminate findings, more than half did not require repeat DOTA PET. Despite advantages over cross-sectional imaging, DOTA PET is not recommended in staging after completely resected appNEN.

Topics: Adolescent; Adult; Aged; Appendiceal Neoplasms; Female; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Multimodal Imaging; Neoplasm Recurrence, Local; Neuroendocrine Tumors; Organometallic Compounds; Positron-Emission Tomography; Prognosis; Retrospective Studies; Tomography, X-Ray Computed; Young Adult

Approximately 5% to 15% cases of endogenous Cushing syndrome are due to ectopic adrenocorticotrophic hormone (ACTH)-producing neuroendocrine tumors, which are commonly located in bronchopulmonary system, thymus, and gastrointestinal tract including pancreas. Although carcinoid tumors of the appendix are revealed in 0.3% of patients undergoing routine appendectomy, ACTH-secreting appendicular carcinoid is a rare entity. We present a case of a 22-year-old woman with ectopic ACTH-dependent Cushing syndrome due to an appendicular carcinoid, which was localized with the help of Ga-DOTATATE PET/CT scan.

Topics: Appendiceal Neoplasms; Cushing Syndrome; Female; Humans; Organometallic Compounds; Positron Emission Tomography Computed Tomography; Young Adult

Ga-DOTATATE PET/CT is increasingly used to image somatostatin receptor expressing tumors. Various intracranial tumors including medulloblastoma are known to express somatostatin receptors. We present a case of incidental cerebellar medulloblastoma on a staging Ga-DOTATATE PET/CT for appendiceal carcinoid.

Topics: Adult; Appendiceal Neoplasms; Carcinoid Tumor; Cerebellar Neoplasms; Female; Humans; Incidental Findings; Intestinal Neoplasms; Medulloblastoma; Organometallic Compounds; Positron Emission Tomography Computed Tomography