concerned about lump on dogs chest

Question
Hello, I have a 32 lb Golden Retriever/Sheltie mix who is approximately 4 1/2 years old. A year ago, she developed a lump on her breast bone area. I took her to the vet, they did a culture, and said it was just a fatty tissue common to dogs although she was young to be already getting these. Should I get a second opinion. It seems like the bump is not larger in diameter but it protrudes significantly. In addition, any time I try and check it out, she looks straight up at me and licks me over and over.. as to say.. yes, there is something wrong, or that hurts, etc. Your opinions? She is on monthly heartguard prevention and sees the doctor yearly for check ups. Thanks in advance for your time.

Answer
Fatty tumors are relatively common, though as your veterinarian stated she is in the younger end of the age spectrum.  If you are concerned that there still may be something wrong having her examine by a second veterinarian is certainly reasonable.  Your peace of mind is very important and if they find only the same harmless fatty tumor it was still a worthwhile visit in my opinion.

Best of luck to you and your canine companion.