Added value of post 177Lu Dotatate and Ga PET/CT imaging in prediction and evaluation of treatment response for GEP NETs

#3823

Introduction: Theragnostic approach using 68Ga Dota-peptides (PET) for diagnosis and Lutetium-177 Dotatate (Lutate) for therapy is approved in gastroenteropancreatic neuroendocrine tumors (GEP-NET). The 24-hour post-Lutate treatment imaging (Lutate post tp) evaluates the radiotracer distribution.

Aim(s): To assess the potential value of Lutate and PET parameters in predicting and evaluating treatment response.

Materials and methods: We reviewed 12 GEP-NET patients, treated with Lutate, who underwent both PET and CT scan at staging and after therapy (Eot). The region of interest (ROI) of each lesion was drawn in the first Lutate scan and was reported in other cycles. From each ROI, we extracted the media value of counts (AVG) and calculated percentage difference (PG). From PET, we extracted SUVmax, somatostatin receptor expression and total lesion somatostatin receptor expression (TLSRE) and calculated PG. We evaluated RECIST and PERCIST criteria from CT and PET. We divided patients in stable disease (SD), progression disease (PD) and partial response (PR) according to follow-up (FU). Only significant ANOVA and correlation coefficients were retained (p<0.05).

Conference:

Presenting Author: Abenavoli E

Authors: Abenavoli E, Linguanti F, Briganti V, Antonuzzo L, Mungai F,

Keywords: Lutetium-177 Dotatate, 68Ga-Dota peptide, evaluation response, prediction response, imaging parameter,