68Ga-DOTATOC safe in children with solid tumors with high SSTR2 levels
Key Takeaways
Molecularly targeted positron emission tomography (PET) using 68Ga-DOTA-Tyr3-octreotide (68Ga-DOTATOC) is safe, sensitive, and specific in children and young adults with solid tumors expressing high levels of somatostatin receptor type 2 (SSTR2), according to study results presented at the North American Neuroendocrine Tumors (NANETS) 2017 Symposium, October 19-21, 2017, in Philadelphia, PA.
“We hypothesize that 68Ga-DOTATOC PET/CT will be both sensitive and specific in the diagnosis of solid tumors in children and young adults that express SSTR2,” noted lead author M. Sue D’Orisio, MD, PhD, pediatric oncologist, University of Iowa Hospitals & Clinics, Iowa City, IA, and fellow researchers.
They used data from three completed, prospective, clinical trials designed to assess the safety and efficacy of 68Ga-DOTATOC PET/CT in subjects aged 6 months to 90 years. For their current study, Dr. D’Orisio and colleagues included 26 children and young adults aged 16 months to 29 years to assess the safety and efficacy of 68Ga-DOTATOC PET/CT. Subjects were administered a dose of 0.043 mCi/kg, with a minimum of 0.3 mCi and a maximum of 3 mCi in those less than 18 years, and a maximum of 4 mCi for young adults.
Safety was assessed via laboratory studies and patient/parent reporting of symptoms before and after the scan. Scan interpretations consisted of a consensus by two board-certified nuclear medicine physicians done in a blinded fashion.
Neuroendocrine tumors were the most common (n=10), followed by appendiceal carcinoid (n=6), suspected neuroendocrine tumors (n=4), paraganglioma (n=3). Neuroblastoma, medulloblastoma, supratentorial pancreatic neuroendocrine tumors, and meningioma were diagnosed in one patient each.
These researchers found that 68Ga-DOTATOC PET/CT had a sensitivity of 88% (14 true positive, 2 false negative), a specificity of 100% (10 true negatives, 0 false positives), a positive predictive value of 100%, and a negative predictive value of 83%.
No serious adverse events (AEs) occurred in either children or young adults. Nine Grade 1 AEs occurred in 26 subjects.
“68Ga-DOTATOC PET/CT has low radiation dose and patient-friendly imaging schedule in a single visit for neuroendocrine tumors, medulloblastoma, and atypical meningioma. 68Ga-DOTATOC PET/CT is the technique of choice for diagnosis and staging of metaiodobenzylguanidine (MIBG) negative neuroblastoma and paraganglioma,” concluded these authors.
This study was supported by the National Cancer Institute; the Iowa Neuroendocrine Tumor SPORE; and the National Heart, Lung, and Blood Institute.