When giving hypofractionated ablative doses of radiation for cholangiocarcinoma, do you give concurrent Xeloda or hold chemo during radiation?

There is no direct evidence to answer this question. In general I have recommended giving concurrent capecitabine because I use a low dose PTV (BED of 50 or so), a high dose PTV (BED of 100 or so)... and sometimes also an ultra high PTV (BED 150 or so) in the center. The high dose PTV often has to be carved out of bowel, so the GTV coverage can drop to 90% or lower. The low dose PTV also covers microscopic extension. So, with the rationale that there are cold areas and subclinical areas, along with the fact that it is well tolerated, I advocate for capecitabine when I use 67.5Gy in 15 (37.5Gy low dose PTV) or 75 Gy in 25 (45Gy low dose PTV). I do not when I use 50Gy in 5 or 60Gy in 10.