SBRT-LDRT-Cadonilimab for Advanced Gastric, Colorectal and Ovarian Cancers With Peritoneal Metastases

"Radiation: Stereotactic Body Radiation Therapy (SBRT)~* Stereotactic Body Radiation Therapy (SBRT) will be performed first at a total dose of 20-50 Gy, delivered in 3-5 fractions of 6-10 Gy each. And the target area was specifically selected based on the location and size of the patient's tumor.~Radiation: low-dose radiotherapy (LDRT)~* Whole-abdominal low-dose radiotherapy will be initiated within 10 days of the end of SBRT with a total dose of 7-15 Gy at 0.5-2.0 Gy twice daily. And the target area included all suspicious tumor tissues and potential metastatic foci in the abdominal cavity."

· Cadonilimab: 6 mg/kg IV, D1, Q2W, until disease progression, death, toxicity intolerance or withdrawal of informed consent