Anti-cytokeratin antibody,known to be a consistent marker for conventional and chondroid chordoma [20], was usedto label the tumor cells green (AlexaFluor 555, Figure 4, bottom panels) and to create atumor specific mask within which red anti-PTEN signals were automaticallyquantitated (CY5, Figure 4,bottom panels). Here, PTEN is linked to chordoma.