Comparing 68Ga-FAPI PET-Guided Abdominal Radiotherapy Combined With Second-Line Standard Therapy and Cadonilimab Versus Second-Line Standard Therapy in Colorectal Cancer With Peritoneal Metastasis

"Radiotherapy: Low-dose radiotherapy to the abdominal cavity region, 5-10 Gy/5 fractions. For visible local lesions, large fraction radiotherapy is administered, 15-30 Gy/5 fractions, once daily.~Immunotherapy: One week after the completion of radiotherapy, cadonilimab, 6 mg/kg, is administered every two weeks."

Standard second-line treatment regimen: (XELOX/FOLFOX or XELIRI/FOLFIRI + bevacizumab/ cetuximab)