brandyv (66.2 days ago) I have a large hard mass in my breast. It`s as big as a golf ball. When I first noticed it, it didn`t hurt. It does now only because my breasts hurt being pregnant. I was scared to death of cancer, but it didn`t just show up and stay. Mine could be felt when I thought I was pregnant, but wasn`t, a year ago then went away. Now that I`m pregnant, it`s back and bigger than before. Anyway, the radiologist and ultrasound tech decided that my large lump is just very dense breat tissue. I read that the painful lumps are usually fluid filled and less cause of worry (rarely cancerous). I was told that the large mass in my breast must be reacting to hormones and to keep an eye on it, but not to worry. If your doctor is concerned about it, you`ll probably get an ultrasound of your breast while you`re pregnant. Possibly a mammogram, but that can expose your baby to radiation.