Secondary outcomes
ascites, tumor, death, stomach cancer, carcinomatosis, Cancer
CANCER, ASCITES, INTRAOPERATIVE COMPLICATIONS, TUMOR, ADVERSE EVENTS, COMPLICATIONS, STOMACH CANCER, REGRESSION, REGRESSION, METASTASES, CARCINOMATOSIS, DIAGNOSE DISEASE

ORR according to RECIST v. 1.1 criteria in the CT-scan after all experimental treatment;The median number PIPACs that can be utilized through the treatment protocol;PIPAC characteristics (procedure time; intraoperative complications; length of a hospital stay after PIPAC; 30 day re-hospitalization rate);Postoperative complications after PIPAC: assessed within 30 days after the PIPAC procedure and classified according to the Clavien-Dindo classification;Peritoneal carcinomatosis index (PCI) measured at 2nd and 3rd PIPAC;Histological regression of peritoneal metastases assessed by Peritoneal Regression Grading Score [The volume of ascites measured at every PIPAC;Biochemical tumor response: the concentration of carcinoembryonic antigen (CEA) and stomach cancer marker (Ca72-4);Quality of life: it will be measured routinely using standard EORTC QLQ-C30 and EORTC QLQ-STO22 quality of life questionnaires;Overall survival: defined as the time from the start of the treatment to study to death by any cause;Progression-free survival: defined as the time from the start of the treatment to the progression of the disease diagnosed on CT scan or laparoscopy;Toxicity according to the National Cancer Institute (NCI) Common Terminology Criteria (CTC) for adverse events v 5.0;Biomarkers: gut microbiome composition, blood, and fecal biomarkers;