My story. Very itchy psoriasis, spreading

Dear all, My first message ever in a psoriasis forum :-) About 13 years ago I noticed a red spot in my armpit. It was very itchy and didn't disappear with time. Instead, it spread and extended. Not only itchy, it could also be painful (may be because of too much scratching). My armpit started looking very ugly. I went to the doctor (dermatologist), she wasn't sure what was that and did a biopsy. Diagnose: psoriasis. Since then, I have been treating it with steroids pomade. For many years I managed to keep it controlled using steroids from time to time (1 week treatment, 3-5 days w/o treatment). Last month, it started on my other armpit too. These are like red spots that grow, spread, change their location. They are very itchy. Last week it also started on my chest. The steroid pomada is not helping much now - it helps, but if I stop using it for one day things get worse very quickly. I wanted to share this story and get feedback from others who may have gone through this. Helps for reading, Federico