Abstract: Peritoneal metastases (PM) are defined as the primary or secondary occurrence/progression of malignant tumor in peritoneum. PM were previously thought to be a terminal disease without effective treatment, with short survival and poor prognosis. With the change in the understanding of PM, the oncology communities regard it as a curable regional cancer metastasis, and create a comprehensive treatment technology system with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy as the core, and establish professional PM treatment centers based on this. The professional PM treatment centers have significantly prolonged the survival of patients, and some patients can even achieve clinical cure. However, in China, there are very few professional PM treatment centers, but the number of PM patients is huge, and most of the patients can't receive professional treatment, resulting in poor survival and prognosis. Based on the cancer statistics in 2015 published by China National Cancer Center Registry and clinical outcome literature on peritoneal metastasis, this paper uses clinical epidemiology methodology to calculate the number of newly diagnosed patients with peritoneal metastasis, to estimate the number of specialized peritoneal cancer centers required, to provide data support for the promotion of professional treatment technology system for PM in our country, and to boost the development of peritoneal oncology.