Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Oct;94(40):e1281.
doi: 10.1097/MD.0000000000001281.

Somatostatin Receptor SSTR-2a Expression Is a Stronger Predictor for Survival Than Ki-67 in Pancreatic Neuroendocrine Tumors

Shreya Mehta  1 , Philip R de Reuver, Preetjote Gill, Juliana Andrici, Lisa D'Urso, Anubhav Mittal, Nick Pavlakis, Stephen Clarke, Jaswinder S Samra, Anthony J Gill
Affiliations

Somatostatin Receptor SSTR-2a Expression Is a Stronger Predictor for Survival Than Ki-67 in Pancreatic Neuroendocrine Tumors

Shreya Mehta et al. Medicine (Baltimore). 2015 Oct.

Abstract

Somatostatin receptors (SSTR) are commonly expressed by neuroendocrine tumors. Expression of SSTR-2a and SSTR-5 may impact symptomatic management; however, the impact on survival is unclear. The aim of this study is to correlate SSTR-2a and SSTR-5 expression in pancreatic neuroendocrine tumors (PNETs) with survival. This study is designed to determine the prognostic significance of somatostatin receptors SSTR-2a and SSTR-5 in PNETs. This retrospective cohort study included cases of resected PNETs between 1992 and 2014. Clinical data, histopathology, expression of SSTR and Ki-67 by immunohistochemistry, and long-term survival were analyzed. A total of 99 cases were included in this study. The mean age was 57.8 years (18-87 years) and median tumor size was 25 mm (range 8-160 mm). SSTR-2a and SSTR-5 expression was scored as negative (n = 19, 19.2%; n = 75, 75.8%, respectively) and positive (n = 80, 80.1%; n = 24, 24.2%). The median follow-up was 49 months. SSTR-2a expression was associated with improved overall survival, with cumulative survival rates at 1, 3, and 5 years being 97.5%, 91.5%, and 82.9%, respectively. Univariate analysis demonstrated better survival in SSTR-2a positive patients (log rank P = 0.04). SSTR-5 expression was not associated with survival outcomes (log rank P = 0.94). Multivariate analysis showed that positive SSTR-2a expression is a stronger prognostic indicator for overall survival [Hazard Ratio (HR): 0.2, 95% Confidence interval (CI): 0.1-0.8] compared to high Ki-67 (HR: 0.8, 95% CI: 0.1-5.7). Expression of SSTR-2a is an independent positive prognostic factor for survival in PNETs.

PubMed Disclaimer

Conflict of interest statement

The authors have no conflicts of interest to disclose.

Figures

FIGURE 1
FIGURE 1
Kaplan–Meier analysis showing overall survival PNET patients (n = 99).
FIGURE 2
FIGURE 2
Comparison of overall survival in patients with PNET with SSTR-2a score ≤1 and SSTR-2a score >1.
FIGURE 3
FIGURE 3
Comparison of overall survival in patients with PNET with SSTR-5 score ≤1 and >1.
FIGURE 4
FIGURE 4
Comparison of overall survival in patients with PNET with grade 1, grade 2, and grade 3 PNETs based on their Ki-67 labeling index results.
See this image and copyright information in PMC

References

    1. Fraenkel M, Kim MK, Faggiano A, et al. Epidemiology of gastroenteropancreatic neuroendocrine tumours. Best Pract Res Clin Gastroenterol 2012; 26:691–703. - PubMed
    1. Wei IH, Harmon CM, Arcerito M, et al. Tumor-associated macrophages are a useful biomarker to predict recurrence after surgical resection of nonfunctional pancreatic neuroendocrine tumors. Ann Surg 2014; 260:1088–1094. - PMC - PubMed
    1. Fazio N, Cinieri S, Lorizzo K, et al. Biological targeted therapies in patients with advanced enteropancreatic neuroendocrine carcinomas. Cancer Treat Rev 2010; 36:S87–S94. - PubMed
    1. Furukori M, Imai K, Karasaki H, et al. Clinicopathological features of small nonfunctioning pancreatic neuroendocrine tumours. World J Gastroenterol 2014; 20:17949–17954. - PMC - PubMed
    1. Vinik A. Advances in diagnosis and treatment of pancreatic neuroendocrine tumors. Endocr Pract 2014; 20:1222–1230. - PubMed