On the value of Ki-67 in the prognostic grading of pancreatic neuroendocrine neoplasms: an update

In 1983, Gerdes, Schwab, Lemke and Stein reported upon a new monoclonal antibody which was generated by immunizing mice with nuclei of the Hodgkin lymphoma cell line L428. This antibody was found to label nuclei of proliferating cells including tumor cells. In their report the authors therefore concluded that “Ki-67 (a name derived from the city of Kiel where the authors worked, and the number 67 of the original clone in the 96-well plate) may be a potent tool for easy and quick evaluation of the proportion of proliferating cells in a tumour”(1). As the exact function of the protein was not well characterized, the initial name Ki-67 was kept. The original antibody which worked only on frozen material, was subsequently replaced by antibodies such as the monoclonal MIB-1 which were found to react with Ki-67 in formalin-fixed and paraffinembedded tissues. Using this antibody it was possible to perform large-scale studies to assess the proliferative activity in different neoplasms (2, 3).