Hi -
I don't' understand what causes the sppike in the enzyme number. I had Big Time liver mets and took Taxol, navelbine & Herceptin weekly. I did not have such a problem and wonder if there is another answer to what is causing this. I, too, would be scared to go off Herceptin and/or chemo if I had not gotten to a stage of remission. Thankfully, I reached NED, and can still have my Herceptin. All my liver functions are normal as can be.