Aberrant expression of Nectin 4 was shown for several cancer entities, including ovarian cancer with comparable expression frequencies in primary serous tumors, i.e., 47%, not discriminating between high and low grade, and higher frequencies in metastases, i.e., 79%, in serous ovarian cancer metastases (of unknown origin, peritoneal local or “real” distant) [33]. This evidence concerns the gene NECTIN4 and cancer.