FMT+ QL1706+Bevacizumab+ XELOX as First-line Treatment for Advanced MSS-type Colon Cancer With Liver Metastasis

Participants will receive FMT combined with QL1706+Bevacizumab+XELOX for 6 cycles. If there is no progression of the disease after 6 cycles of the first-line treatment, then patients will enter the maintenance treatment stage. The therapy of maintenance treatment stage was at the discretion of the investigator.