[Call for attention to the value and challenge of liquid biopsy in diagnosis and treatment for peritoneal metastasis of gastric cancer].

Peritoneal metastasis is the common route of metastasis in gastric cancer and is a major cause of death in advanced gastric cancer. Early intervention with comprehensive treatment can effectively improve the prognosis of some patients with peritoneal metastasis. However, early peritoneal metastasis in gastric cancer is predominantly micro-metastasis, which cannot be effectively evaluated by imaging studies. Moreover, the detection of disseminated cancer cells in peritoneal lavage suffers from a low detection rate and significant heterogeneity. In recent years, the development and application of new liquid biopsy technologies such as circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) have provided new means to assess potential peritoneal metastasis at the cellular and molecular levels, gradually becoming research hotspots in this field. This review will summarize the relevant progress of liquid biopsy in peritoneal metastasis, which holds significant importance for improving the prognosis of gastric cancer patients in China.