Sign of liver cancer

I was diagnosed with Hairy Cell Leukemia a little over a year ago. In August 2006 I received chemo (claribidine) to fight the HCL which was found during a biopsy of my Hip. A May 2007 PET-CT shows no more HCL in my hip, however there is still uptake in my liver (focal liver lesion). My oncologist does not think the liver abnormality represents HCL, but is unsure what the uptake may represent. Since I am in good health, my blood test were normal, and the history (2 1/2 years worth) of my CT's showing very slow growth in the liver lesion she suggested waiting 6 months (Novemeber 2007) to have another CT-Scan done and then have a biopsy if warranted.

I have been feeling great, but then 3 weeks ago, I had some soreness behind my right ribs (front upper) and then there is some soreness behind my right ribs on my backside and located near the middle or bottom part of my ribs. If I lay on my back, my right side is definitely sore and if I try to roll over to my right side becomes painful near the rib area. The soreness feels like someone punched me in this area. Some days it is better than others. I have had this soreness for 3 weeks. How can I determine if it is a muscle pull or someting more serious. Other than the soreness in the right ribs my health is still great.

Is this a muscle pull, how do I further access ?