if from puberty...all these drugs are not going to cure you bro...take it from someone who has tried the aifm, letro, cab, etc.
surgery is our only option. genetics fucked us.
could you give specifics of the protocols you used (including duration of use, dosing, calorie deficit, on/off gear, use of any topical or oral anti-androgens and/or estrogens- eg. spirolactone, finasteride, tea trea oil/lavender containing products (highly reccomend you check your hair and body products (shampoos, gels, soaps, lotions, etc) for these compounds- they are in a lot of them), any medications, etc.)
while some cases of gynecomastia may require surgery, certainly not most do. And just because the gyno was pubertal does not make it more or less likely to regress. Quite often there are flaws in treatment protocols or they are not engaged in long enough.
now it may be that your case wont respond regardless of protocol perfection or duration, but more likely than not elements were there that should not have been or elements were not there that should have been.
generally the longer you have the issue and the more developed it is, particularly ductal growth, the longer it will take to regress.
btw- would really like to see your protocols, it can be helpful to others.