What Can I Do About my Back Acne?

I am 27 years old & have had back+chest acne since I was 11 years old. I used to have acne on my face, but that went away completely by the time I was 18 without any medications. In college I went through several courses of different antibiotics & birth control/spironolactone to no response. I was finally put on Accutane which helped a great deal (for two courses of 6 month each), but once I stopped it all came back in full force. I haven't been on any medication for acne since 2006.