mystery dark spots...

in the past month i have been wary of a dark spot on my inner thigh and found a similar congregation of spots under my breast. im a relatively healthy 17 yr old... and doubtful that it's skin cancer but cautious nonetheless. I just found it odd that these few spots are in sunless areas... ill keep an eye on them... hoping that no more arise. should i worry?

[Fuzzz]

You should have them looked at.  It is actually not uncommon to get skin cancer in sunless places, or something else entirely that is also better treated early.  See a dermatologist.  No reason to take chances.  

[Dennis MD]

Hi.
From your post, it seems that the dark spots on your inner thigh and under your breast are post inflammatory hyperpigmentation.  Perhaps you had a skin infection like a fungal infection on those areas.  Fungal infection is common in areas with moist skin like the inguinal or axillary area, or the area under the breasts.  
I think you need to consult your dermatologist for evaluation.  You should also keep those areas you mentioned dry.  
Take care.