First Ex Vivo Results of β--Radioguided Surgery in Small Intestine Neuroendocrine Tumors with 90Y-DOTATOC.

Background: In neuroendocrine tumor (NET), complete surgery could better the prognosis. Radioguided surgery (RGS) with β--radioisotopes is a novel approach focused on developing a new probe that, detecting electrons and operating with low background, provides a clearer delineation of the lesions with low radiation exposition for surgeons. As a first step to validate this procedure, ex vivo specimens of tumors expressing somatostatin receptors, as small intestine neuroendocrine tumor (SI-NET), were tested. Materials and Methods: SI-NET presents a high uptake of a beta-emitting radiotracer, 90Y-DOTATOC. Five SI-NET patients were enrolled after performing a 68Ga-DOTATOC positron emission tomography/computed tomography (CT) and a CT enterography; 24 h before surgery, they received 5 mCi of 90Y-DOTATOC. Results: Surgery was performed as routine. Tumors and surrounding tissue were sectioned in different samples and examined ex vivo with the beta-detecting probe. All the tumor samples showed high counts of radioactivity that was up to a factor of 18 times higher than the corresponding cutoff value, with a sensitivity of 96% and a specificity of 100%. Conclusions: These first ex vivo RGS tests showed that this probe can discriminate very effectively between tumor and healthy tissues by the administration of low activities of 90Y-DOTATOC, allowing more precise surgery.

Citation

Emilio Bertani, Francesco Collamati, Marzia Colandrea, Riccardo Faccini, Nicola Fazio, Mahila E Ferrari, Marta Fischetti, Uberto Fumagalli Romario, Luigi Funicelli, Micol De Simoni, Carlo Mancini-Terracciano, Riccardo Mirabelli, Silvio Morganti, Stefano Papi, Eleonora Pisa, Elena Solfaroli-Camillocci, Francesca Spada, Marta Cremonesi, Chiara M Grana. First Ex Vivo Results of β--Radioguided Surgery in Small Intestine Neuroendocrine Tumors with 90Y-DOTATOC. Cancer biotherapy & radiopharmaceuticals. 2021 Jun;36(5):397-406

PMID: 33601932

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