What do these blood numbers mean?

My husband has melanoma, spread to his liver.  He started dacarbazine(sp?) last week, plus interferon.  His blood test, ggt jumped up to 400 and ldh jumped up to 2000+, liver aches, these were all "normal" before dacarbizine .. doctor says it doesnt matter, dont worry about it, dont pay attention to it, etc.  WHAT DOES IT MEAN????  My cousin says dacarbizine can kill your liver, so what do these tests mean what is happening.  No one will talk to me about it, it's just "not important" but 10X the normal upper limit???  Excuse me?  Any info is appreciated.  He is healthy, athletic, tough, except for stage 4 melanoma.