I think massage can help because it increase blood flow to the
region. Its a bit like exercising can keep one healthy due to
better blood circulation. Makes sense? However, i think it will be
more useful during puberty since at that time the female and growth
hormones secretion is much higher that usual. I also heard of
movies stars recommending massage as their method for breast
enhancement,however for this case it is debatable as there is lack
of scientific explanation or proof. 
