Comparison of 68Ga-DOTA-NaI3-Octreotide/tyr3-octreotate positron emission tomography/computed tomography and contrast-enhanced computed tomography in localization of tumors in multiple endocrine neoplasia 1 syndrome

Abstract

The optimum imaging modality for the screening of multiple endocrine neoplasia type 1 (MEN1)-associated tumors is not well established. Here, we compare the performance of contrast-enhanced CT (CECT) versus 68 Ga DOTA-NOC/TATE PET/CT in MEN1 patients. The retrospective case record study is conducted at a tertiary health-care center. Thirty-four patients, who have undergone both CECT and 68 Ga DOTA-NOC/ TATE PET, were included in the analysis. CECT had higher per-lesion sensitivity than 68 Ga DOTA-NOC/TATE PET/CT for the detection of parathyroid lesions, (82.6% vs. 24.6%, P < 0.001). 68 Ga DOTA-NOC/TATE PET/CT had higher per-lesion sensitivity than CECT for the detection of metastases (85% vs. 47.5%, P < 0.001) and gastrinomas (90% vs. 10%, P = 0.003). When combined use of the two imaging modalities is compared to CECT alone (63.7% vs. 93.1%, P = 0.00012) and 68 Ga-DOTA-NOC/TATE PET/CT alone (74.1% vs. 93.1%, P = 0.0057), it provided significantly higher per-lesion sensitivity for the detection of gastroenteropancreatic neuroendocrine tumors (GEP-NETs). 68 Ga-DOTA-NOC/ TATE PET was more sensitive for the detection of gastrinomas and metastases than CECT, whereas it was less sensitive for the detection of parathyroid lesions than CECT. The combined use of both the imaging modalities significantly increases the sensitivity for detection of GEP-NETs.

Imaging surveillance in multiple endocrine neoplasia type 1: Ten years of experience with somatostatin receptor positron emission tomography

“…In the most recent clinical practice MEN1 guideline it is suggested that local expertise and availability may determine the surveillance program. 1 At present, nine studies have reported data on the use of SRI PET/CT in the surveillance of MEN1 patients [18][19][20][21][22][23][24][25][26] but only four explicitly investigated the role of SRI PET in relation to change in treatment. Three supported the use of SRI PET since the PET signal had a significant impact on the decision to do primary pancreatic surgery 19,23,24 and one did not 18 since PET only led to a change in treatment in 1/33.…”

“…Subsequently, nine studies investigating the use of SRI PET/CT in MEN1 patients, have been published with conflicting results. [18][19][20][21][22][23][24][25][26] The aim of this retrospective study was to investigate the impact of SRI PET in a cohort of MEN1 patients. Primary outcomes were: Inclusion criteria were patients with a MEN1 diagnosis based on the identification of a pathogenic or probably pathogenic MEN1 gene variant classified according to the guidelines from The American College of Medical Genetics.…”

“…The 2012 clinical practice guidelines for patients with MEN1 was published before the era of SRI PET. Subsequently, nine studies investigating the use of SRI PET/CT in MEN1 patients, have been published with conflicting results 18–26 …”

Value of Somatostatin Receptor PET/CT in Patients With MEN1 at Various Stages of Their Disease

“… 68 Ga-Ga-DOTA-TOC detected 15 of 25 subcentimetric duodenopancreatic lesions that were not visualised by CECT. Finally, Patil et al, have reported their experience from a retrospective analysis of 34 MEN1 patients evaluated by either  68 Ga-Ga-DOTA-TATE or NOC and CT (16). PET was found to detect more lesions than CT (per-lesion: 74.1% vs 63.7%, p=0.23 and per-patient: 89.2% vs 71.4%, p=0.09), with a PPV of 100% for both modalities.…”

“…SSTR PET has progressively replaced somatostatin receptor scintigraphy (SRS) due to its many advantages (i.e., greater image resolution, shorter imaging times, lower radiation exposure, cheaper costs in properly equipped departments). At present, the value of SSTR PET/CT in MEN1-associated NETs has been evaluated in six studies with very promising results in terms of lesion detection and impact on patient management (12)(13)(14)(15)(16)(17)(18). Overall, SSTR PET often detects more primary NETs (except thymic carcinoids) and metastases than morphological imaging, with very few false positives.…”