My oldest ferret (approaching 4 and a half) was recently diagnosed with adrenal disease.  I'm a bit of a dilemma as to the best way to proceed with treatment, since I am located in Japan and options are limited here. 

My vet has said that basically all adrenal ferrets in Japan are treated with monthly lupron injections and that surgery is rarely performed, but he would be comfortable doing the surgery if I wanted to.  I was under the impression that the norm was the opposite, with surgery being the most common option and medical treatment used only in cases where surgery would be too risky.  My girlie is otherwise healthy and I have been anticipating the surgery for years now (she's always had a tail on the thinner side and before we moved overseas my vet back in the United States said that she's a likely candidate for adrenal in the future) but now I am feeling confused and don't want to demand something as drastic as surgery when it is against my vet's judgement.  

Could anyone point me in the direction of advice about adrenal surgery vs. medical treatment?