Fig. 1: An example of the use of a digitalized system for assessing Ki-67 in pancreatic neuroendocrine neoplasms is shown here.

This is a particularly illustrative case due to the presence of a lymphocytic infiltrate at the tumor periphery, which represents a potential source of bias for Ki67 assessment with digital systems. A A pancreatic neuroendocrine tumor, G2, is shown. (Hematoxylin-eosin, 10x original magnification); B the digitalized system can count all cells present in a specific field, also on hematoxylin-eosin slides; C, D modern systems can select a specific area for the Ki-67 count: in this example, the field with lymphocytes has been excluded from the count, reducing potential important biases in tumor grading (Ki67 immunohistochemistry, 10x original magnification).