Superiority of Ga-DOTATATE over F-FDG and anatomic imaging in the detection of succinate dehydrogenase mutation (SDHx )-related pheochromocytoma and paraganglioma in the pediatric population.

Purpose: To evaluate and compare diagnostic performance of Ga-DOTA(0)-Tyr(3)-octreotate (Ga-DOTATATE) with F-fluoro-2-deoxy-D-glucose (F-FDG) positron emission tomography-computed tomography (PET/CT) and anatomic imaging using computed tomography and/or magnetic resonance (CT/MR) imaging in detection of SDHx-related pheochromocytomas and paragangliomas (PPGLs) in pediatric patients.

Methods: Nine pediatric patients (5:4, girls:boys; 14.6 ± 2.0 years) with an SDHx-related mutation (SDHB:SDHA:SDHD, n = 7:1:1) were included in this retrospective study. At the time of initial diagnosis, 7/9 patients had metastatic disease. They underwent CT/MR imaging along with PET/CT using Ga-DOTATATE (n = 9), F-FDG (n = 8), and positron emission tomography-magnetic resonance imaging (PET/MR) using F-FDG (n = 1). In this manuscript, F-FDG PET/CT refers to both F-FDG PET/CT and F-FDG PET/MR. The per-lesion, per-region, and per-patient detection rates were compared and calculated for each of the imaging modalities. A composite of all functional and anatomic imaging studies served as the imaging comparator.

Results: Eight out of nine patients were positive for PPGLs on the imaging studies that demonstrated 107 lesions in 22 anatomic regions on the imaging comparator. The per-lesion detection rates for Ga-DOTATATE PET/CT, F-FDG PET/CT, and CT/MR imaging were 93.5% (95%CI, 87.0% to 97.3%); 79.4% (95%CI, 70.5% to 86.6%); and 73.8% (95%CI, 64.5% to 81.9%), respectively. The per-lesion detection rate for Ga-DOTATATE PET/CT was significantly higher than that of F-FDG PET/CT (p = 0.001) or CT/MR imaging (p < 0.001). In all of the anatomic regions except abdomen, the per-lesion detection rates for Ga-DOTATATE PET/CT was found to be equal or superior to F-FDG PET/CT, and CT/MR imaging. The per-region detection rate was 100% (95%CI, 84.6% to 100%) for Ga-DOTATATE PET/CT and 90.9% (95%CI, 70.8% to 98.9%) for both F-FDG PET/CT and CT/MR imaging. The per-patient detection rates for Ga-DOTATATE PET/CT, FDG PET/CT, and CT/MR imaging were all 100% (95%CI, 63.1% to 100%).

Conclusion: Our preliminary study demonstrates the superiority of Ga-DOTATATE PET/CT in localization of SDHx-related PPGLs in pediatric population compared to F-FDG PET/CT and CT/MR imaging with the exception of abdominal (excluding adrenal and liver) lesions, and suggests that it might be considered as a first-line imaging modality in pediatric patients with SDHx-related PPGLs.