“…Based on the site of the lesion, skin metastases are classified as metastatic umbilical tumors, which are known as Sister Joseph nodules (SJNs), and non-SJN skin metastases (Figure 1) (Tables S1–S4) [17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58]. Skin metastases can further be divided according to the time of appearance: Skin metastases at initial diagnosis and skin recurrences.…”