Comparison of integrin αvß3 expression with 68Ga-NODAGA-RGD PET/CT and glucose metabolism with 18F-FDG PET/CT in esophageal or gastroesophageal junction cancers.

ABSTRACT

BACKGROUND: The primary aims of this study were to compare in patients with esophageal or esophagogastric junction cancers the potential of 68Ga-NODAGA-RGD PET/CT with that of 18F-FDG PET/CT regarding tumoral uptake and distribution, as well as histopathologic examination. METHODS: Ten 68Ga-NODAGA-RGD and ten 18F-FDG PET/CT were performed in nine prospectively included participants (1 woman; aged 58 ± 8.4 y, range 40-69 y). Maximum SUV (SUVmax) and metabolic tumor volumes (MTV) were calculated. The Mann-Whitney U test and Spearman correlation analysis (ρ) were used. RESULTS: 68Ga-NODAGA-RGD PET/CT detected positive uptake in 10 primary sites (8 for primary tumors and 2 for local relapse suspicion), 6 lymph nodes and 3 skeletal sites. 18F-FDG PET/CT detected positive uptake in the same sites but also in 16 additional lymph nodes and 1 adrenal gland. On a lesion-based analysis, SUVmax of 18F-FDG was significantly higher than those of 68Ga-NODAGA-RGD (4.9 [3.7-11.3] vs. 3.2 [2.6-4.2] g/mL, p = 0.014). Only one participant showed a higher SUVmax in an osseous metastasis with 68Ga-NODAGA-RGD as compared to 18F-FDG (6.6 vs. 3.9 g/mL). Correlation analysis showed positive correlation between 18F-FDG and 68Ga-NODAGA-RGD PET parameters (ρ = 0.56, p = 0.012 for SUVmax, ρ = 0.78, p < 0.001 for lesion-to-background ratios and ρ = 0.58, p = 0.024 for MTV). We observed that 18F-FDG uptake was homogenous inside all the confirmed primary sites (n = 9). In contrast, 68Ga-NODAGA-RGD PET showed more heterogenous uptake in 6 out of the 9 confirmed primary sites (67%), seen mostly in the periphery of the tumor in 5 out of the 9 confirmed primary sites (56%), and showed slight extensions into perilesional structures in 5 out of the 9 confirmed primary sites (56%). CONCLUSIONS: In conclusion, 68Ga-NODAGA-RGD has lower potential in the detection of esophageal or esophagogastric junction malignancies compared to 18F-FDG. However, the results suggest that PET imaging of integrin αvß3 expression may provide complementary information and could aid in tumor diversity and delineation. TRIAL REGISTRATION Trial registration NCT02666547. Registered January 28, 2016-Retrospectively registered, https//clinicaltrials.gov/ct2/show/NCT02666547 .