ERBB2 and metastatic malignant neoplasm in the lymph nodes: Several studies [13, 14, 18–20] have reported various prognostic factors that predict the poorer outcome of EMPVD, including dermal invasion, lymph node metastasis, stage [13, 14], tumor coexisting histology of adenocarcinoma [2] or vulvar carcinoma, positive surgical margins [2], HER-2/neu overexpression [19] and high expression of Ki-67 [20].