68ga-dotatate pet/ct compared with 131i-mibg spect/ct in the evaluation of neural crest tumors

Objective(s): 68ga-dotatate positron emission tomography (pet)/computed tomography (ct) has shown promising results in imaging of neural crest tumors (nct). herein, we compared the performance of 68ga-dotatate pet/ct and 131i-mibg single photon emission computed tomography (spect)/ct in the initial diagnosis, staging and follow-up of patients with ncts. methods: twenty-five patients (males:females=8:17; age range=2–71 years) with clinically proven or suspicious neuroblastoma, pheochromocytoma (pcc) or paraganglioma (pgl) were enrolled in this prospective study and underwent both 68ga-dotatate pet/ct and 131i-mibg spect/ct. a composite reference standard derived from histopathological information, together with anatomical and functional imaging findings, was used to validate the results. imaging findings were assessed on a per-patient and on a per-lesion basis. sensitivity and accuracy were assessed using mcnemar’s test. results: referring to radiological imaging and histopathological findings as reference standard, 68ga-dotatate and 131i-mibg scans showed a sensitivity and accuracy of (100%, 96%) and (86.7%, 88%), respectively, on a per-patient basis. in pcc/pgl patients, on a per-patient basis, the sensitivity of 68ga-dotatate was 100% and that of 131i-mibg was 77.8%. in neuroblastoma patients, on a per-patient basis, the sensitivities of both 68ga-dotatate and 131i-mibg were 100%. overall, in this patient cohort, 68ga-dotatate pet/ct identified 52 lesions and 131i-mibg spect/ct identified only 30 lesions. on a per-lesion analysis, 68ga-dotatate was found to be superior to 131i-mibg in detecting lesions in all anatomical locations, particularly osseous lesions. according to the mcnemar test results, differences were not statistically significant. conclusion: this relatively small patient cohort suggests 68ga-dotatate pet/ct be superior to 131i-mibg spect/ct in providing particularly valuable information for both primary staging and follow-up in patients with nct.