Having lost several birds to various reproductive cancers, I would think that once they are symptomatic it's probably too late to save them, if it is indeed cancer. They are so good at hiding the early signs that it's usually pretty advanced by the time you realize there is a problem. I think the study linked is interesting, and may be way to reduce the incidence, not sure if it would actually cure, or prolong life in a bird that already had developed a cancer.
I've always been of the opinion that if something is not going to cause harm, or prolong suffering needlessly, then there is no reason not to try.
In the case of surgery, birds tend to not do well with the anesthesia, it's risky in itself. I personally would need to have a pretty good idea that doing surgery would result in a positive outcome, at least a fairly high percentage of probable success, before I would be willing to put them through it. I would not do it for a maybe. That's just me personally.
I've always been of the opinion that if something is not going to cause harm, or prolong suffering needlessly, then there is no reason not to try.
In the case of surgery, birds tend to not do well with the anesthesia, it's risky in itself. I personally would need to have a pretty good idea that doing surgery would result in a positive outcome, at least a fairly high percentage of probable success, before I would be willing to put them through it. I would not do it for a maybe. That's just me personally.