title: Radio-guided surgery with the use of [99mTc-EDDA/HYNIC]octreotate in intra-operative detection of neuroendocrine tumours of the gastrointestinal tract.
abstract: OBJECTIVE
  Radio-guided surgery (RGS) is an intra-operative localising technique which enables identification of tissue "marked" by a specific radiotracer injected before surgery. It is mainly used for sentinel node mapping and for detection of parathyroid adenomas and other tumours, including neuroendocrine tumours of the gastrointestinal tract (GEP-NET). The aim of this study was to determine whether intra-operative radio-detection with the use of [(99m)Tc-EDDA/HYNIC]octreotate, a new somatostatin analogue, is able to reveal an unknown primary and secondary sites, thereby improving surgical treatment and the final outcome of GEP-NET.
  
  
  METHODS
  The study group included nine patients with suspected GEP-NET (four carcinoids, five pancreatic NET) localised with somatostatin receptor scintigraphy (with [(99m)Tc-EDDA/HYNIC]octreotate), who had negative results on other pre-operative imaging tests. At surgery, suspected tumours were measured in situ and ex vivo and precise exploration of the abdominal cavity was performed with the intra-operative scintillation detector (Navigator).
  
  
  RESULTS
  Intra-operative gamma counting localised three carcinoids. In one patient SRS was false positive (owing to inflammatory infiltration). Compared with SRS, RGS revealed additional lymph node metastases in one case. RGS resulted in successful localisation of all pancreatic NET (the smallest lesion was 8 mm in diameter).
  
  
  CONCLUSIONS
  [(99m)Tc-EDDA/HYNIC]octreotate SRS followed by RGS is a promising technique to improve the rate of detection and efficacy of treatment of GEP-NET, especially in the presence of occult endocrine tumours. The imaging properties of [(99m)Tc-EDDA/HYNIC]octreotate and the 1-day imaging protocol offer opportunities for more widespread application of this tracer followed by RGS in oncology.
authors.affiliation: Nuclear Medicine Unit of the Department of Endocrinology, Medical College at Jagiellonian University, 31-501 Cracow, Poland. alahub@cm-uj.krakow.pl
authors.forename: A
authors.initials: A
authors.lastname: Hubalewska-Dydejczyk
authors.forename: J
authors.initials: J
authors.lastname: Kulig
authors.forename: P
authors.initials: P
authors.lastname: Szybinski
authors.forename: R
authors.initials: R
authors.lastname: Mikolajczak
authors.forename: D
authors.initials: D
authors.lastname: Pach
authors.forename: A
authors.initials: A
authors.lastname: Sowa-Staszczak
authors.forename: K
authors.initials: K
authors.lastname: Fröss-Baron
authors.forename: B
authors.initials: B
authors.lastname: Huszno
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018278:Carcinoma, Neuroendocrine / Q000000981:diagnostic imaging* / Q000601:surgery*; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D007430:Intraoperative Care / Q000379:methods; D008297:Male; D008875:Middle Aged; D015282:Octreotide / Q000031:analogs & derivatives*; D015609:Organotechnetium Compounds; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C526854:technetium Tc 99m (EDDA-HYNIC)octreotate; D015282:Octreotide