Hi Helen;
I experienced exactly the same scenerio. Thought I was stage 1 with a small lesion in my breast only to find a 3 cm liver met. I did weekly chemo with herceptin (taxotere and xeloda) for 25 weeks (~ equivalent to 8 rounds) and the liver met eventually dissappeared competely. Since the chemo you were on appears to be working I would continue with the additional 2 rounds before I opted for a surgical or other method of removal.
I should also mention that for awhile my liver met was just "stable" and did not continue to shrink. It also showed no activity on a PET scan so we stopped the harsh chemo and I remained on herceptin only every 3-week. For several months we all wondered if it was scar tissue or dormant cells. Just when I finally decided to have a liver resection it totally dissapeared. It must have in the end been scar tissue and took a few monhts for my body to reabsorb the dead cells.
Also at stage IV it is best to try and avoid surgery unless it is really needed. There is some evidence, athough weak, that growth factors present in wound healing can possibly "wake" up sleeping micro mets. This is one of Al's favorite topics

. I am not really convinced by most of the science articles on this topic but on the other hand I don't want to find out the hard way they are right.
take care
kk1