If the pigmentation also present on the neck or elbows or groin area it could be an endocrine cause like acanthosis nigricans. any preexisting lesions could also have a pigmentation mark. melasma can also present at atypical sites. An examination would be needed to comment accurately. You can consult online with me by sending pictures and we can address it accordingly. Hope this was helpful.
Answered2017-10-25 06:01:44
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