On 2015 Mar 22, Richard Jahan-Tigh commented:

I think this is probably just a Becker's nevus with breast hypoplasia. A nontender,non-pruritic brownish patch evolving over 2 years (probably when puberty started for her) and continuing to be asymptomatic for 3 more years afterwards doesn't really describe morphea. Morphea characteristically spares the nipple and doesn't prevent the breast from completely forming as in this case.

On 2015 Mar 22, Richard Jahan-Tigh commented:

I think this is probably just a Becker's nevus with breast hypoplasia. A nontender,non-pruritic brownish patch evolving over 2 years (probably when puberty started for her) and continuing to be asymptomatic for 3 more years afterwards doesn't really describe morphea. Morphea characteristically spares the nipple and doesn't prevent the breast from completely forming as in this case.