Fig. 2

Dispersion indices of the parameters evaluated in the individual patients. This dispersion index is a measure of homogeneity of judgement of one parameter in individual patients by several observers. Zero describes a perfect match of all observers. a When the index of dispersion was calculated for the individual vessels evaluated by the surgeons, the dispersion of evaluated tumor contact was not different between the vessels. b To evaluate the influence of the degree of tumor contact to the peripancreatic vascular structures, cases were classified for their anatomical resectability in resectable, borderline resectable and locally advanced. The average of the dispersion index of tumor contact to the vasculature was similar in patients with resectable, borderline resectable, and locally advanced tumors indicating the degree of tumor contact does not influence the observation of tumor abutment to vessels. c Using the same classification, analyses of the dispersion index of the judgement of resectability indicated, however, that the homogeneity of the conclusion drawn from the observation of tumor contact to the blood vessels depended significantly on the degree of tumor abutment. Especially in patients with resectable and borderline resectable tumors, the heterogeneity in the judgement of resectability was significantly decreased (P < 0.05) indicating a gap between anatomical resectability and subjective judgement by the individual surgeon