Brief Answer:
Not of health concern, would have treated you with Hydroquinone cream

Detailed Answer:
Hello and thanks for your query.

I shall make an effort to provide you with good professional recommendations specific to your questions.
When though it is difficult comment without examination and only based on the picture. But I have gone through the picture, it does not appear to be of any health concern.

It may be result of exposure to sun or effect of pressure on back due to long time sitting. I would suggest you to use tightly-knit fabric while going outdoors and to use some passing while sitting for long duration.

I would have prescribed you with Hydroquinone products in conjunction with retinoids as cream(evecream) applied twice daily, but these agents are prescription based drugs.

Yet , again I duly appreciate your query to me, I do hope that have found something useful to help you and I shall be glad to answer any further apprehensions.

Sincerely,

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Brief Answer:
It is padding and use thick cloths

Detailed Answer:
Hi
Good to hear from you.
Yes I referred some thick cloth while going out. It padding not passing sorry for that.
Presently I would advice you to avoid constant friction that occurs while sitting. I feel based on the picture these measures, these should reduce.
Instead of Hydroquinone product, use either continue to use fade cream that you are trying for while and observe for any change.
Hope you have got something helpful from here.
Take care

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