Clinical Usefulness of Somatostatin Receptor Scintigraphy in Japanese Patients with Gastroenteropancreatic Neuroendocrine Tumors

Abstract

Background/Aims: Somatostatin receptor (SSTR) scintigraphy (SRS) is the standard imaging modality for evaluation of gastroenteropancreatic neuroendocrine tumor (GEP-NET) in Western countries. However, this modality was not approved in Japan until recently. The purpose of this study was to evaluate the clinical efficacy of SRS for detecting GEP-NET in Japanese patients. Methods: Japanese patients with advanced GEP-NET were enrolled and evaluated by the SRS and CT. We also compared SRS and immunohistochemical expression of SSTR type 2a (SSTR2a). Results: We enrolled 16 patients and the primary sites were the pancreas in 9, the stomach in 1, the small intestine in 2, the colon in 3, and unknown in 1. SRS showed positive findings in 3 (100%) of grade 1 (G1) and in 12 (92.3%) of grade 2 (G2) lesions. In the liver, SRS and CT detected lesions in 13 and 14 cases, respectively. The concordance rate of SSTR2a expression with SRS findings was 93.8% in the whole body and 92.9% in the liver. Conclusions: SRS could detect almost all of G1 and G2. SRS could be useful to detect lesions, with a high concordance rate with CT and pathological findings. We confirmed that SRS is a useful and reliable modality for Japanese patients.

The role of somatostatin receptor scintigraphy in the diagnosis and follow-up of the pancreatic neuroendocrine neoplasms

“…Al-Chalabi et al [22], em phasized the role of SPECT/CT es pe cially in elim i nated places of phys i o log i cal ac tiv ity, thus de creas ing FP and FN re sults. Hasegawa et al [23] found in NET (includ ing pan creas) that SRS showed pos i tive find ings in 3 (100 %) of grade 1 (G1) and in 12 (92.3 %) of grade 2 (G2) le sions with high con cor dance rate with SSTR2 ex pres sion (93.8 % in the whole body and 92.9 % in the liver). Etchebehere et al [24] ob tained a signif i cant dif fer ence in detectability of PanNEN between 68 Ga-SSA, SRS SPECT/CT, and dif fusion-weighted whole body MRI (re spec tively, sen si tiv i ties of 0.96, 0.60, and 0.72; specificities of 0.97, 0.99, and 1.00; PPV of 0.94, 0.96, and 1.00; NPV val ues of 0.98, 0.83, and 0.88; and ac cu ra cies of 0.97, 0.86, and 0.91).…”

Primary hepatic neuroendocrine neoplasm diagnosed by somatostatin receptor scintigraphy: A case report

“…Volante et al [ 12 ] defined scores of 2 (membranous reactivity in less than 50% of tumor cells) and 3 (circumferential membranous reactivity in more than 50% of tumor cells) as positive. Hasegawa et al [ 13 ], who analyzed 16 cases of NEN, reported that the concordance rate between accumulation in a lesion on SRS and pathological SSTR2a expression was 93.8%.…”

Usefulness of selective arterial calcium injection tests for functional pancreatic neuroendocrine tumors

“…Although we considered excluding these two patients, there are only a few patients that undergo the SACI tests and this study already had a small number of patients; thus, we included these two patients and the time span became long. Finally, among 14 patients, 8 patients (57.1%) underwent EUS [10][11][12]25 , 4 (28.6%) underwent 18F-FDG PET/CT 26 , and 2 (14.3%) underwent somatostatin receptor scintigraphy (SRS) 27 . We have been performing EUS on patients with pancreatic neuroendocrine tumors (PNETs) since 2007, and now we perform EUS more actively in most patients with PNETs, future prospective research studies are needed to confirm and evaluate these preliminary findings, by including EUS, 18F-FDG PET/CT, and 68 Ga-PET/CT, all of which are useful to evaluate the location of PNETs.…”