I had the same, left hepatic lobe resection, clean margins and the final pathology report was clean as well. My lovely cardiologist said "I want you to see an oncologist". OK, did that. The oncologist, another lovely lady read the final path report somewhat differently than the surgeon. The pathologist had noted that some of the removed tissue was particularly aggressive. She said, if any of that material got loose during surgery, it could be bad. So she ordered six months of Gemzar, to start about two months after surgery. The downside of the chemo was I got no regrowth of the liver. That was about two years ago and so far, still clean.
From what I've casually observed, there's no clear protocol for CC treatment. The oncologist pointed out when she ordered Gemzar, that there's no clear evidence it's effective against CC. For us as patients, you just have to trust the judgment of the professionals and not get too worked up when you see different protocols than yours that appear effective.
Hospitals/Doctors Link, Our Experiences: http://www.cholangiocarcinoma.org/punbb/viewtopic.php?id=3126 See page 4 of thread for Dr. Tomoaki Kato info.
Major USA Cancer Centers: http://www.cholangiocarcinoma.org/majorcancercenters.htm