Immunostaining showed positive result for cadherin 17; focally positive results for caudal-related homeobox gene 2 (CDX2), cytokeratin 20 (CK20), and synaptophysin; and negative results for cytokeratin 7 (CK7), neural cell adhesion molecule (CD56), and paired box 8, which were consistent with primary colorectal adenocarcinoma. The gene discussed is KRT7; the disease is colorectal adenocarcinoma.