I would like to share my female piggie's experience with a cyst. She was perfectly healthy but one day I noticed a lump on her side that was not there a week ago. It was about the size of a dime. I took her to the vet and they tried to get some fluid out of the lump but couldn't. They prescribed her antibiotics for two weeks and said that if it was an abcess it would go away but if it didn't she would need surgery. Well it didn't go away so I took her in for surgery. It went really well and she came back with stitches. ($400) They said it looked just like a cyst not cancer so I was relieved. I kept her seperated from her buddy within the same cage. She ate and drank perfectly after. I took her stitches out two weeks later and she has been healthy ever since. I was nervous when I found the lump and all through the process because I didn't want to lose my piggie. If you have a similar problem with your guinea pig please don't hesitate to ask any questions. I had a hard time finding information when I found the lump.