Brief Answer:
A condition without a definitive cure and of obscure origin.

Detailed Answer:
I read your question carefully and I understand your concern.

Unfortunately lichen sclerosus doesn't have any definitive cure. Medication may bring some improvements but not in all patients.

The corticosteroids that you have already tried have been shown by studies to be the most effective medication so your doctors were correct in prescribing them.

If they are shown not to be effective other options may include calcineurin inhibitors like tacrolimus or pimecrolimus. Their effect does take longer than steroids and won't necessarily bring benefit.

As for the cause medicine has made little advancement in that direction as well. It is known to be due to inflammation and increased activity of fibroblasts in the skin layers. It is not known what initiates that though. There are several theories like autoimmune reaction, antibodies against connective tissue components, supported by the higher frequency of other autoimmune conditions in lichen patients. There are genetic theories as well, it is found more frequently in relatives. Viral infections may play a role as well by triggering autoimmune response. They are all only theories though.

I remain at your disposal for other questions.

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