The association of 18F-fluorodeoxyglucose PET/computed tomography parameters with tissue gastrin-releasing peptide receptor and integrin αvβ3 receptor levels in patients with breast cancer

OBJECTIVE: Gastrin-releasing peptide receptor (GRPR) and integrin alphavbeta3 receptors are significantly associated with primary breast cancer, neovascular endothelial, and metastatic tumor cells. We aimed to evaluate GRPR and integrin alphavbeta3 receptor staining, F-FDG uptake patterns and possible prognostic factors in breast cancer. METHODS: Ninety lesions of 87 subjects diagnosed with breast cancer were included in this prospective study. The sections were stained with GRPR and integrin alphavbeta3. Subjects were divided into four molecular subgroups: luminal A, luminal B, triple negative and HER2. PET/CT imaging was performed on all subjects. The groups were compared in terms of GRPR and integrin alphavbeta3 staining properties, possible prognostic factors and mean SUVmax values. RESULTS: Increased F-FDG uptake was significantly associated with estrogen receptor and progesterone receptor negativity. Molecular subtypes were significantly associated with mean integrin scores (P = 0.030), while histopathological subtypes were significantly associated with mean GRPR scores (P = 0.029). Increased integrin alphavbeta3 expression is significantly associated with ER and PR negativity. Additionally, GRPR score was significantly correlated with estrogen receptor and progesterone receptor expression scores and a negative statistically significant correlation was detected between integrin and progesterone receptor scores. Mean primary lesion SUVmax had a statistically significant positive correlation with integrin alphavbeta3 score. CONCLUSION: GRPR and integrin alphavbeta3 expression results are complementary to F-FDG PET/CT findings, and are also significantly correlated with hormone receptors associated with aggressive subtypes. These results may pave the way for GRPR and integrin alphavbeta3 targeted imaging with Ga-labeled molecules and systemic radionuclide treatment with Lu-labeled compounds.