How serious SCLE really is?

Hello. I am 35 years old woman.
When I came back from my holydays at the sea this year I’ve noticed a dry rash on my upper back and chest. I didn’t know what it is but I supposed that it was some sun allergy.
I used some crèmes to reduce it but nothing helped.
Nobody knew what it is?
I had to seek for medical help, and so I did. Doctor, after he examined me, told me devastating news-I have a very serious skin disease called subacute cutaneous lupus erythematosus.
He didn’t know to tell me is this from too much sun exposing or something else. If out there somebody had a similar problem-please tell me what do you know about this terrible disease.

I have lupus for over than five years now.
I have read your post and I have some informations for you.
First of all, lupus is not skin disease. It is a autoimmune disease.
Subacute cutaneous lupus erythematosus (SCLE) is a
non–atrophy-producing photosensitive dermatosis.
It causes non-itchy ring-shaped dry rash over whole body often following sun exposure-like in your case.
The condition is also often mild and does not affect the central nervous system or kidneys.
The main cause of therapy is to improve the patient's appearance and to prevent the development of further lesions.
Treatment of cutaneous LE includes sun protection and use of topical and oral steroids.
With good therapy you have best chances to get better and even forgot you had skin problems.