A new and simple on-line tool to differentiate neuroendocrine and solid pseudopapillary pancreatic tumors

Objectives. To propose an multidetector computed tomography-based tool for quantitative differentiation between pancreatic neuroendocrine tumour (PNET) and solid pseudopapillary neoplasm (SPN) in clinical practice.

Methods. The retrospective study included 76 patients from January 2014 to March 2018. The final cohort of sixty-two patients was divided into two groups: PNET and SPN. Two radiologists independently analyzed MDCT data. We constructed two multivariable prognostic models for differential diagnosis between hypervascular PNETs and SPN, nonhypervascular PNETs and SPN via binary logistic regression. We used the receiver operating characteristic (ROC) curves to evaluate the prognostic value of any quantitative characteristics and to determine optimal cut- off values for differential diagnosis.

Results. Thirty patients with PNET comprised the first group. Thirty-two patients with SPN comprised the second group. For the first prognostic model selecting a cut-off value of 34% yielded the maximum sensitivity and specificity of 96.7% and 93.8%, respectively. Values larger than the cut-off value correlated with PNET. For the second prognostic model, selecting a cut-off value of 50% yielded the maximum sensitivity and specificity of 100% and 100%. Values larger than the cut-off value correlated with PNET.

Conclusion. We developed two diagnostic models for differential diagnosis between hypervascular, nonhypervascular PNETs and SPN. The models allow for increased confidence in the diagnosis. Finally, we created an on-line calculator for easy routine use http://pancreas-calculator.com).

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