My brother started getting these dry, white patches on his skin a little while ago. It started out with just one patch, but more started showing up and migrating up his arm, almost in a perfect line. They are about the size of poker chip (sorry, that's all i could think of^^). He has maybe five or six of them now, and we just discovered another one on his cheek. We're not too worried about it, but we were just wondering if anyone might know what it could be. Any idea? And should we take him to a dermatologist?