I'm going to third the suggestion of a picture of the problem.
It sounds to me, though, that you might be trying to take in too much fabric with too few seams. Are you using a five-piece pattern (two pieces for the front, two for the sides, and one for the back)? If you don't have those side pieces, you might want to consider adding them in. That way you have seams that transition from the chest to the side and from the side to the back. And if you need even more seams to complete your shaping, you can still add darts in the front and back pieces.
"Not a word."