Immunohistochemical demonstration of the KI-67-antigen in paraffin-embedded tumor biopsies.

10 tumor specimens were processed according to a modification of the AMeX method, which allows for paraffin embedding plus immunostaining of the slices. We used this method to determine the growth fraction of tumors using the monoclonal antibody KI-67. Results were essentially the same as those obtained when studying frozen sections. The quality of the histological slices is equal to frozen sections, but greater areas of tumor can be examined. Furthermore, this method allows for compilation of a stock of tumor specimens which can be used for further immunohistochemical studies whenever needed.