dual 64cu-dotatate and 18f-fdg pet/ct imaging of patients with neuroendocrine neoplasms

Conditions: GEP-NET; Neuroendocrine Tumors; Neuroendocrine Carcinoma; Neuroendocrine Carcinoma Metastatic

Summary: prospective clinical trial investigating combined, dual 18f-fdg pet/ct and 64cu-dotatate pet/ct imaging of patients with gastroenteropancreatic neuroendocrine neoplasms (gep-nen)

patients with neuroendocrine neoplasms (nen) represent a heterogeneous disease group with variable prognosis. nen most frequently arise from the gastrointestinal tract or the pancreas; collectively termed gep-nen. grading of gep-nen is based on tumor proliferation index (ki-67) from biopsies or surgical resection specimens into: low grade g1 neuroendocrine tumor (net) (ki-67\ 20). high grade nens are further categorized according to tissue morphology into well-differentiated g3 neuroendocrine tumors (net) and poorly differentiated neuroendocrine carcinomas (nec). a common feature of most nets is the overexpression of somatostatin receptors (ssr) on the tumor cell surface. whole-body pet/ct imaging with radiolabelled ssr-targeted tracers, e.g. 64cu-dotatate, plays a key role in diagnosis, staging, treatment selection and response evaluation of patients with net. measurements of 64cu-dotatate tumor standardized uptake values (suv) and tumor volume on pet/ct provide prognostic value for patients with net. patients with high grade nen often have lower ssr expression and ssr pet/ct is infrequently routinely performed in these patients. however, we expect that the suv and tumor volume from 64cu-dotatate pet/ct also holds prognostic information for patients with high grade nen and that some patients may prove eligible for prrt based on the scans. 18f-fdg pet/ct imaging is widely used in cancers, but is routinely primarily reserved for patients with high grade nen. however, 18f-fdg pet/ct also holds prognostic information for patients with lower grade net. by combining 64cu-dotatate pet/ct and 18f-fdg pet/ct imaging, we expect to obtain complementary prognostic information for patients with gep-nen of all grades. in this clinical trial, we will therefore investigate and compare the tumor phenotypes found on 64cu-dotatate pet/ct and 18fdg pet/ct performed within 4 weeks in patients with gep-net g1-3 and gep-nec. the aim of the trial is to establish prognostic models for progression-free-survival (psf) and overall survival (os) including tumor status (positive/negative), suv measurements, and tumor volume derived from the dual 64cu-dotatate pet/ct and 18fdg pet/ct scans.

Eligibility criteria:
inclusion criteria: * histopathologically verified gastro-entero-pancreatic neuroendocrine neoplasm (gep-nen) or patients with unknown primary tumor with metastases with verified nen positive histopathological examination suggesting gep origin * world health organization (who) performance status 0-2 * must be able to read and understand the patient information in danish and to give informed consent exclusion criteria: * pregnancy * breast-feeding * weights more than the maximum weight limit for the pet/ct bed of the scanner (140 kg) * uncontrolled diabetes * uncontrolled infection * exacerbation in autoimmune diseases * other active cancer disease * conditions or diseases (e.g. uncontrolled parkinson's disease) making the patient unable to lie still in the scanner * severe claustrophobia * localized neuroendocrine neoplasms of the appendix, the rectum measuring \< 1 cm, and ecl-omas of the stomach * history of allergic reaction attributable to compounds of similar chemical or biologic com-position to 18fdg or 64cu-dotatate