Computed tomography features in prediction of histological differentiation of pancreatic neuroendocrine neoplasms - a single-centre retrospective cohort study.

Purpose: The aim of our study was to analyse the histological differentiation and computed tomography imaging features of pancreatic neuroendocrine neoplasms (PNENs).

Material and methods: We performed a retrospective single-centre cohort study of 157 patients with histologically confirmed PNEN. We compared the results of the preoperative biopsy from the tumour with reports of the multi-slice computed tomography performed by a radiologist with 30 years of clinical practice.

Results: Specific computed tomography (CT) features are associated with histological differentiation, such as enhancement in the arterial phase (p = 0.032), Wirsung's duct dilatation (p = 0.001), other organ infiltration (p < 0.001), distant metastases (p < 0.001), and enlarged regional lymph nodes (p = 0.018). When there is an organ infiltration, the likelihood of the tumour having histological malignancy grades G2 or G3 triples (95% CI: 1.21-8.06). Likewise, the existence of distant metastases increases the risk almost fourfold (95% CI: 1.44-10.61), and a tumour size of 2 cm or larger is linked to a nearly threefold rise in the risk of histological malignancy grades G2 or G3 (95% CI: 1.21-6.24).

Conclusions: Certain CT characteristics: enhancement during the arterial phase, Wirsung's duct dilatation, organ infiltration, distant metastases, and the enlargement of regional lymph nodes are linked to histological differentiation.