Incremental value of99mTc-HYNIC-TOC SPECT/CT over whole-body planar scintigraphy and SPECT in patients with neuroendocrine tumours.
OBJECTIVE
The aim of this study was to evaluate the additional value of99mTc-HYNIC-TOC SPECT/CT over planar whole-body (WB) scintigraphy and SPECT alone in the detection and accurate localisation of neuroendocrine tumour (NET) lesions.


METHODS
This study included 65 patients with a definitive histological diagnosis of NET prior to scintigraphy. Planar WB scintigraphy, SPECT, and SPECT/CT images were acquired at 4 h post-administration of 670 MBq99mTc-HYNIC-TOC. Additional SPECT images at 10 min after tracer administration were also acquired. Clinical and imaging follow-up findings were considered as the reference standards (minimum follow-up period, 15 months). Patient and lesion-based analyses of the efficacies of the imaging modalities were performed.


RESULTS
While 38 patients exhibited metastasis of NETs, 27 presented no evidence of metastasis. Upon patient-based analysis, the sensitivity and specificity of SPECT/CT were found to be 88.9 and 79.3 %, respectively. The diagnostic accuracies of WB scintigraphy, 4h-SPECT, and SPECT/CT were 72.3, 73.8, and 84.6 %, respectively. The area under curve (AUC) value for SPECT/CT (0.84) was the highest, followed by those for 4h-SPECT (0.75) and WB scintigraphy (0.74). The accuracy and AUC values of SPECT/CT were significantly better compared to those of WB scintigraphy (p < 0.001), 10 min-SPECT (p < 0.001), and 4 h-SPECT (p = 0.001). The findings of SPECT/CT led to the change in treatment plan of 11 patients (16.9 %).


CONCLUSIONS
The sensitivity and diagnostic accuracy of SPECT/CT in the evaluation of NET lesions outperforms planar WB imaging or SPECT alone.
Mate Trogrlic, MD,, Department of Nuclear Medicine, University Hospital Center Zagreb, Kispaticeva 12, 10000 Zagreb, Croatia, Fax: 0038512376040, E-Mail: mate.trogrlic@gmail.com.
Mate
M
Trogrlic
Stanko
S
Težak
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging* / Q000473:pathology; D015282:Octreotide / Q000031:analogs & derivatives*; D015609:Organotechnetium Compounds; D011877:Radionuclide Imaging / Q000379:methods*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000072098:Single Photon Emission Computed Tomography Computed Tomography / Q000379:methods*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D051598:Whole Body Imaging / Q000379:methods*
D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C410263:technetium Tc 99m hydrazinonicotinyl-Tyr(3)-octreotide; D015282:Octreotide
neuroendocrine tumours; receptors somatostatin; technetium 99m EDDA-HYNIC-Tyr(3)-octreotide