AIM: In combined positron emission tomography/computed tomography (PET/CT) of neuroendocrine neoplasms using (68)Ga-DOTA(0)-Phe(1)-Tyr(3)-octreotide ((68)Ga-DOTATOC), partial volume effects (PVEs) may occur in smaller lesions. This study determined the lesional cutoff size for the occurrence of PVEs in a clinical setting. METHODS: Retrospective assessment of 51 PET/CT examinations (16-slice PET/CT device) for malignant PET foci was carried out. In all foci, the maximal standardized uptake value (SUVmax) and maximal lesion diameter on axial CT was documented. Determined SUVmax and lesional sizes were correlated via LOESS regression. In the resulting curve, the cutoff point for SUVmax size dependency was determined visually and mathematically using 2 approximating straight lines. RESULTS: In 45 patients, 313 of 413 PET foci found were malignant, measurable on CT and had a roughly spherical geometry (SUVmax: 2.5-103.3, mean ± SD 20.5 ± 15.18; CT diameter: 5-103 mm, mean ± SD 21.8 ± 13.1 mm). The cutoff lesional size for the occurrence of PVEs was 20.4 mm by the mathematical approach and 25 mm by visual assessment. CONCLUSION: In (68)Ga-DOTATOC imaging, the clinical lesional size threshold is far larger than expected from systemic resolution only. Thus, tracer uptake quantification is only acceptable in sufficiently large lesions.
AIM: In combined positron emission tomography/computed tomography (PET/CT) of neuroendocrine neoplasms using (68)Ga-DOTA(0)-Phe(1)-Tyr(3)-octreotide ((68)Ga-DOTATOC), partial volume effects (PVEs) may occur in smaller lesions. This study determined the lesional cutoff size for the occurrence of PVEs in a clinical setting. METHODS: Retrospective assessment of 51 PET/CT examinations (16-slice PET/CT device) for malignant PET foci was carried out. In all foci, the maximal standardized uptake value (SUVmax) and maximal lesion diameter on axial CT was documented. Determined SUVmax and lesional sizes were correlated via LOESS regression. In the resulting curve, the cutoff point for SUVmax size dependency was determined visually and mathematically using 2 approximating straight lines. RESULTS: In 45 patients, 313 of 413 PET foci found were malignant, measurable on CT and had a roughly spherical geometry (SUVmax: 2.5-103.3, mean ± SD 20.5 ± 15.18; CT diameter: 5-103 mm, mean ± SD 21.8 ± 13.1 mm). The cutoff lesional size for the occurrence of PVEs was 20.4 mm by the mathematical approach and 25 mm by visual assessment. CONCLUSION: In (68)Ga-DOTATOC imaging, the clinical lesional size threshold is far larger than expected from systemic resolution only. Thus, tracer uptake quantification is only acceptable in sufficiently large lesions.
Authors: L Bodei; M Kidd; I M Modlin; V Prasad; S Severi; V Ambrosini; D J Kwekkeboom; E P Krenning; R P Baum; G Paganelli; I Drozdov Journal: Eur J Nucl Med Mol Imaging Date: 2015-05-07 Impact factor: 9.236
Authors: Kjell Oberg; Eric Krenning; Anders Sundin; Lisa Bodei; Mark Kidd; Margot Tesselaar; Valentina Ambrosini; Richard P Baum; Matthew Kulke; Marianne Pavel; Jaroslaw Cwikla; Ignat Drozdov; Massimo Falconi; Nicola Fazio; Andrea Frilling; Robert Jensen; Klaus Koopmans; Tiny Korse; Dik Kwekkeboom; Helmut Maecke; Giovanni Paganelli; Ramon Salazar; Stefano Severi; Jonathan Strosberg; Vikas Prasad; Aldo Scarpa; Ashley Grossman; Annemeik Walenkamp; Mauro Cives; Irene Virgolini; Andreas Kjaer; Irvin M Modlin Journal: Endocr Connect Date: 2016-08-31 Impact factor: 3.335