Stage IV gastric cancer is classified into four subcategories: positive peritoneal cytology without clear macroscopic peritoneal involvement (surgery is usually performed in these cases); gross appearance peritoneal carcinomatosis [surgery, eventually with hyperthermic intraoperative peritoneal chemotherapy (HIPEC) may be considered in very selected cases with limited PCI]; nodal metastases outside the loco-regional nodes (surgery may not bedenied for metastatic nodes in stations 13 and 16); and hematogenous metastases (surgery should be performed in selected cases with liver metastases suitable to R0 resection).
PCI was immunolocalized in tissue microarray spots with BPH epithelium (detection rate 100%), PIN lesions (100%), tumors (96%), metastases (88%), and in all cell lines.ISH and WB supported the findings.