The assay requires preparing nine (9) glass slides with serial tissue sections taken at five (5) micron thickness from formalin-fixed, paraffin-embedded tissue blocks. These sections cannot have been treated with Bouin’s reagent or methylene blue. The first section must be stained with hematoxylin and eosin according to a standard protocol; and the remaining eight serial sections will be unstained. All will be shipped in a cork-lined slide box for next day delivery.