Abstract
BACKGROUND: The prognosis of a pancreatic neuroendocrine neoplasm (pNEN) is closely correlated with histological grade. While the role of tomoelastography in predicting tumor grades has been explored in various cancers, evidence regarding its association with the histological grade and clinical features of pNENs remains limited. This study aimed to investigate the association between tomoelastographic parameters and the histological grade and key clinical characteristics of pNENs. METHODS: A retrospective study was conducted on 62 patients with pathologically confirmed pNENs, all of whom underwent tomoelastography prior to surgery without receiving neoadjuvant treatment. Patients were categorized into three groups: G1 (n = 28), G2 (n = 30), and G3/neuroendocrine carcinoma (NEC) (n = 4). The relationship between the tomoelastography parameters and clinicopathological characteristics was analysed by using the Kruskal-Wallis test, Spearman correlation, and ordinal logistic regression. Receiver-operating characteristic curves were used for evaluating the diagnostic performance of tomoelastography. RESULTS: The shear wave speed (c), representing stiffness in tomoelastography, increased with tumor grade (1.63 m/s for G1 vs 2.23 m/s for G2 vs 2.53 m/s for G3&NEC, P < 0.001). Parameter c was positively correlated with the tumor size (r = 0.59, P < 0.001) and Ki67 index (r = 0.44, P < 0.001), and was notably higher in lesions with distant or regional lymph node metastases than in those without metastases. Identified as a hazardous factor for tumor grade (odds ratio = 3.92, 95% confidential interval [CI]: 1.88-8.16), c showed good performance in discriminating between G1 and G2 (area under the curve = 0.81, 95% CI: 0.70-0.93, P < 0.001). CONCLUSION: Tomoelastography offers a promising quantitative tool for assessing the histological grade of pNENs and identifying more aggressive tumor behavior via increased tissue stiffness.