A diagnostic IHC panel for EMPD, consisting of CK7-positive, CK20-positive or CK20-negative, p63-negative, SRY-box transcription factor 10 (SOX10)-negative, and carcinoembryonic antigen (CEA)-positive results, is recommended by existing guidelines [1], but is not available at all sites. The gene discussed is CEACAM5; the disease is extramammary Paget disease.