Radioguided surgery in neuroendocrine tumors using Ga-68-labeled somatostatin analogs: a pilot study.
BACKGROUND
Previous studies of the intraoperative use of a hand-held gamma probe to localize metastases and primary tumors have shown improved assessment of tumor spread and changes in surgical management based on additional information gained by radioguided surgery (RGS).


OBJECTIVE
The aim was to test the feasibility and advantages of doing RGS using a gallium-68 labeled with somatostatin receptor analogs in the intraoperative detection of neuroendocrine tumors.


METHODS
Ga-68 somatostatin receptor PET/CT imaging was performed preoperatively in 9 patients with gastroenteropancreatic neuroendocrine tumors. Statistical analyses were performed to find out the correlation between the pathologic size of the tumor lesions and the maximum standardized uptake value on PET/CT as well as the target/nontarget ratio (T/NT) of gamma probe counts. Thereafter, the impact of the planned operation procedure and the lesion-based sensitivity of tumor detection (surgical palpation vs. PET/CT vs. gamma probe) had been observed.


RESULTS
Overall, 72 locations in 9 patients were examined intraoperatively using gamma probes. The gamma probe detected 94% of the whole histologically quantified lesions, whereas the PET/CT allocated 69% and surgical palpation, 50%. RGS resulted in change in the operative procedure in 56%. There was a significant correlation between the maximum standardized uptake value and tumor size (0.74; P < 0.005).


CONCLUSIONS
Hand-held gamma probe surgery using gallium-68-labeled somatostatin analogs is a feasible and an attractive option for real-time detection of small metastases and primaries of neuroendocrine tumors.
Department of General and Visceral Surgery, Zentralklinik Bad Berka, Bad Berka, Germany. Daniel.Kaemmerer@zentralklinik.de
Daniel
D
Kaemmerer
Vikas
V
Prasad
Wolfgang
W
Daffner
Sven-Petter
SP
Haugvik
Stefan
S
Senftleben
Richard P
RP
Baum
Merten
M
Hommann
D000328:Adult; D000368:Aged; D005260:Female; D005710:Gallium Radioisotopes; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging / Q000601:surgery*; D010865:Pilot Projects; D049268:Positron-Emission Tomography; D016634:Radiosurgery / Q000379:methods*; D013004:Somatostatin / Q000031:analogs & derivatives*; D014057:Tomography, X-Ray Computed
D005710:Gallium Radioisotopes; D013004:Somatostatin