Immunohistochemically, the tumor cells were positive for AE1/AE3 (Figure 1B) and p63, focally positive for CK10 (Figure 1C) and CK14 (Figure 1D), and negative for CAM5.2 and CEA (data not shown), findings which were consistent with cSCC. The gene discussed is KRT10; the disease is skin squamous cell carcinoma.