PET Scan Shows Something in Liver

Hello. 4 months ago, my first PET scan showed my breast tumor, one lymph node in my armpit and one lymph node in my chest. After 13 rounds of chemo, my 2nd PET scan yesterday showed nothing in my breast or lymph nodes. Obviously the chemo is working! However, the doctor was perplexed to see a spot on my liver. Apparently it was there during the first scan but was very dim and the radiologist didn't mention it. They thought it was fatty infultration/inflammation based on the location (near my gall bladder). I guess this is a common spot for fatty infiltration/inflammation. The spot is brighter this time and the doctor says she can't ignore it and has ordered a liver MRI. She says it would be unusual for the chemo to work so well on the breast and lymph nodes, but then have the cancer growing in my liver. Anyone have experience with this? I'm wondering if it could have something to do with my triglycerides being very high most of my adult life. I had finally gotten this under control and stopped taking my cholesterol medication before being diagnosed with breast cancer.I haven't had them checked again, but my eating habits over the last few months make me think they're probably high again.