CISH (Chromogenic In-Situ Hybridization) is a new technique first published by Tanner and his collegues (Am J Pathol 2000, 157:1467-1472). It will likely prove to be much more economical than FISH (FISH can range up to ten times the cost of IHC), and can be conducted with an ordinary microscope. Because it is chromogenic, the signal is permanent, and the brightfield images will be more familiar to anatomic pathologists than fluorescent images, and makes the assessment of tumor morphology more readily available. Below is an image analysis result where the total expression is reported across the sample as a ratio to red and blue expression.
