The peritoneum is the serous membrane covering the abdominal wall from the inside and some organs from the outside (including: stomach, part of the duodenum, small intestine and most of the colon, uterus and ovaries). Metastasis of malignant tumours to the peritoneum is referred to in the TNM classification (T-tumour- tumour, L-lymph nodes - lymph nodes, M- metastasis - metastasis) as distant metastasis, i.e. the M+ feature, and is generally associated with a poor prognosis and a short survival time for untreated patients (approximately 6 months on average). Intraperitoneal chemotherapy in hyperthermia is a salvage procedure for many of them.