my 12 year old son has a lump in his left breast..
Probably part of puberty. I'd say take him to the doctor to find out what it is, but don't worry about breast cancer - his chances of having breast cancer at age 12 are statistically 0%. Good luck - PJH
I just discovered a large lump in my 12yr old son's left breast. He said it hurts, and that it has been there a couple of months.
He began puberty at age 10 (hair under his armpits) and his voice is changing. He has peach-fuzz like facial hair (age 12).
I will not hesitate to take him to the pediatrician.
I will post my findings in the next week or so.