MSH2 and Lynch syndrome: While a complete and lasting treatment remission was only observed in one patient suffering from Lynch syndrome due to a germline mutation in the MSH2 gene, who was treated with an immune checkpoint inhibitor, the overall response rate was 30% (n = 6/20) and the achieved disease control rate was 75% (n = 15/20) indicating that precision oncology may become a new therapeutic standard in the palliative care of iCCA patients.