I got slightly reddish and textured skin around the neck and upper chest... looks a little like the skin is stretched in concentric circles around the neck. I don't think it's stretch marks, I didn't grow that much.
If you look at Arnolds upper chest on the cover of his "bodybuilding encyclopedia" it looks like he has that going on too (which may be the only similarity between my chest and Arnolds.). Also noticed the same kind of skin on Dwayne Johnson in a shot of him lying in a hospital bed.
I assumed it was related to androgens, but I haven't found anything definitive in my searches.