pain in my chest bone

I was born with truncas arteriosis and have had three open heart surgeries to replace my valve. I have alot of pain and soreness in my chest bone here lately. its always been pretty sensitive, but i have lost some weight and the bones are a little more noticble and hav ebecame sore. especially on my left side at the top right above my breast. my dr actually had me go for a breat ultrasound to make sure it wasnt a lump and it wasnt. it worries me cause i dont know what it is some say it culd be a bone spur since ive had my chest sawed open three times and its sore bad some and the sometimes i dont even notice it. i was wondering if i might have something else wrong or if it actually could be a bone spur. i feel good most of the time but i am a smoker and cancer does run in my family and i was worried it might be lung cancer. but im only 25 yrs old so hopefully its not that. what do u think

[kenkeith]

The sternum (breast bone) may not have completely healed.  If it skin related to the area in question, it could be a serious complication indicating infection. However bone (sternum) growth on the other hand takes many months and is not generally cause for concern.  

The ultrasound imaging should have ruled out an abnormality that is solid (which may be a non-cancerous lump of tissue or a cancerous tumor) or fluid-filled (such as a benign cyst) or both cystic and solid. Ultrasound can also help show additional features of the abnormal area.

I am providing a link at may help you address any bone spur questions.
http://www.medhelp.org/health_questions/lump-on-chest-bone

Hope this helps and thanks for the question, and if you have any further questions or comments, you are welcome to responditon a