Brief Answer:
These could be keloids.

Detailed Answer:
Hi,

Thanks for writing to us.

I have seen the picture attached.

We can think of three differentials- acne, sebaceous cyst and keloids. As these are hard touch and have been persistent since years, keloids seems to be the most plausible diagnosis. Keloids are hard elevated skin coloured lesions formed due to disorganised overproduction of collagen. A keloid can form at site of insect bite, minor injury, tattoo, skin piercing, acne etc.

These can simply be treated by intralesional steroid injections. One or two injections at an interval of three to four weeks would be sufficient in your case. You may also apply silicone gel based medicines like kelocote or contractubex twice in a day for resolution. These gels work, however require months to show resolution.

Hope this answered your query.

Take care

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